Final Report Summary - HELIOS (High Energy Lithium-Ion Storage Solutions)
Executive Summary:
Battery reliability and safety are the key issue for the commercialization of x-EV vehicles, especially for High Energy applications, requiring a large amount of energy stored on board.
HELIOS is a 4 year project to carry out a comparative assessment of 4 types of lithium-ion battery technologies, selected as the most promising technologies being developed across the world: NCA, NMC, LMO & LFP/C. The assessments concern traction batteries for the automotive sector (EV, PHEV & HEV-APU). The work achieved from laboratory testing and other analysis deliver the comparative data covering performance, life, cost, recycling and safety/abuse characteristics.
NCA is the current mainstream manufacturing technology used by SAFT and is therefore the base case against which the other 3 technologies are compared using the same design, same electrolyte and same electrode material. In each case the evaluations are carried out on representative size high energy cells (with a capacity of approximately 40 Ah), produced industrially. In total, up to 220 cells have been employed across the various test activities (safety tests on new and pre-aged cells), cycling (EV and PHEV) and calendar tests (12-15 months).
Post-mortem analysis were also performed at 3 different ageing steps (0, 6 and 12/15 months). The main objective, and not the less, is to evaluate the impact of the cell characteristics on the ageing mechanisms.
The main conclusion under all the results is that no chemistry fulfil all the requirements on the performance, durability, economical and safety points of view. The alternative systems (to NCA commercial and reference one) provide a potential for further improvement and possible application.
It needs to be emphasized that the cells were not manufactured on an industrial scale. It’s expected that optimization of the design & the formulation will overcome the life duration problems and improve significantly the energy density.
However, all these results will give a stronger knowledge base to develop the future Electric and Hybrid / Plug-In Hybrid electric vehicles by the vehicle OEM’s and the supply industry. The end result will give, to decision makers, a clearer view of the potentially effective investments in research, development and manufacture. Furthermore they will contribute to the development of x-EV vehicles and so, too long term benefits for the environment, fuel security and European Union employment
Project Context and Objectives:
The automobile industry and urban transport operators must meet the required reduction of the environmental impact of vehicles and thereby contribute to the objectives fixed by the EU Climate and Energy package known as the “Grenelle de l'Environnement”20-20-20 targets: 20 % renewables energies by 2020, 20% reduction of CO2 emissions and fuel consumption from transport. Innovative, safe and with high performance energy storage solutions have to be studied and grow up.
Energy storage is an area of rapidly evolving technology. Lithium-ion has become the dominant rechargeable battery chemistry for consumer electronics devices and is going to become also the most competitive technology for industrial, transportation, and power-storage applications. From a technological point of view, this chemistry provides a high specific energy (Wh/kg) and high energy density (Wh/L) regarding previously popular rechargeable battery chemistries (nickel metal hydride, nickel cadmium, and lead acid battery).
Battery reliability and safety are the key issue for the commercialization of x-EV vehicles.
Objectives and presentation of Helios project :
HELIOS is a 4 year project to carry out a comparative assessment of 4 types of lithium-ion battery technologies, selected as the most promising technologies being developed across the world. The 4 types of positive electrode materials having been selected are :
Lithium Nickel Manganese Cobalt (NMC)
Lithium Manganese oxide - NCA blend (LMO-NCA or LMO-b)
Lithium Iron Phosphate (LFP)
Lithium Nickel Cobalt Aluminium (NCA)
NCA is the current mainstream manufacturing technology used by SAFT and regarded therefore as the base case against which the other 3 technologies are compared. In order to make the comparison easier (changing only one thing at a time: the positive electrode material), electrolyte and negative electrode were kept the same, only adjusting quantities (balancing electrodes capacities and electrolyte quantity) to optimize the cell operation.
The assessments concern traction batteries for the automotive sector (EV, PHEV & HEV-APU).
The work achieved from laboratory testing and other analysis of full sized battery to determine the performance, cycle life and storage life, safety under abuse conditions, volume cost, capability for recycling of material.
The majority of the work was performed at cell level, with some module abuse testing (typically 4 cells). In all cases, the comparative results have been extrapolated to full battery pack size units suitable for complete vehicle. From the results, a recommendation for the future work on electrochemical system was proposed.
Main Results :
The final goal of the investigation is to benchmark the properties of the four different electrochemical systems versus each other and to identify their advantages, disadvantages, risks, challenges.
In order to carry out the testing and analysis work it was necessary to develop procedures for each phase. These documents are available for future use in similar activities:
- Cell specifications applicable to both electric and hybrid electric vehicles (see table1 - figures are included in the pdf file)
- Performance, cycle and ageing test procedures, with links to other existing procedures available world-wide (see public Deliverable 3.2)
- Safety test procedures for performance under electrical/thermal/mechanical accident or abuse for new and aged cells (see public Deliverable 3.3)
- Procedures and recommendation for handling of used cells and recovery of materials (see Deliverables 8.1 & 8.2).
- Electrical tests show that EV & PHEV cycles defined in the project are the most constraining parameter (concerning the cell capacity decrease, and cells power ability decrease in a less extent). Moreover, temperature seems to be a really predominant parameter influencing the cells ageing, though its influence turned out to be more and more important from storage to EV-Cycling and finally PHEV cycling (see figure 1: Capacity decrease for the four chemistries tested in Helios project and for four cycling test conditions (PHEV, EV cycling @ 45°C and calendar life @ 45 and 60°C). NCA and NMC cells show the best performances at 30 and 45°C.
- The safety tests have been performed on 40Ah cells produced by SAFT. Safety is the key point to allow lithium-ion batteries technology to be widely used for electric vehicles. According to the several types of positive active material dealing in the HELIOS project, each of them has not exactly the same performances in terms of specific energy, cycling life time and safety. A review on the chemical runaway mechanism under abuse conditions has been performed and disseminated (see the public deliverable 6.1).
Abusive tests were performed on 40 Ah cells (with new and pre-aged cells).
The three tested technologies could be ranked from the one with the safest behaviour to the lowest as below: LFP (110Wh) ≥ NMC (140Wh) > NCA (150Wh)
This ranking is rather close than the one obtained on small cell (NMC ≥ LFP > NCA) and the same obtained after Differential Scanning Calorimetry measurements on pristine and charged materials.
Regarding the abuse tests on 40 Ah module (without taking into account LMO NCA blend of which capacity is about 28 Ah instead of 40 Ah), crush tests (radial position), nail penetration, short-circuit, thermal stability and overcharge seem to be the most constraining tests.
No technology has a satisfactory behaviour if we consider all the test results at cell level: without BMS (Battery Management System) or casing integration...
- Finally, post-mortem analysis on new, intermediate and final samples showed that :
- Adhesion is one of the main ageing mechanism (but electrode formulations except for NCA were done by labs with low optimisation)
- Dissolution issue with NMC and LFP is activated by the temperature
- Graphite is the limited electrode for the 4 technologies
- for LMO-NCA / Graphite cells, a Mn migration was observed from LMO to NCA particles.
Conclusion and perspectives :
The project is showing significant information on the differences between the 4 cell technologies. This will provide considerable assistance to future R&D and business decision making within the industry. The main results, conclusions obtained within Helios project can be summarized in the table 2 (Overview and synthesis of Helios results).
The NMC based cells showed a slightly lower capacity than the NCA based cells, but continued material improvement and further adaptations in the cell geometry may lead to an equivalent energy density to the current NCA product. LMO/NCA-blend cells are definitely significantly lower in their capacity. Future activities with respect to an optimization in the mass mixture and the recipe may lead to at least partly compensate this disadvantage. LFP based cells were rather disappointing, particularly with regard to life endurance, linked to water content of positive material electrode (water content of raw material, and many transportation steps). It needs to be emphasized that the cells were not manufactured on an industrial scale. It is expected that optimization with this chemistry will overcome the life problem. Also the capacity of these cells may be further increased without sacrificing their advantageous abuse tolerance. This makes them interesting especially for those PHEVs with a relatively small battery system.
Project Results:
HELIOS is a 4 year project to carry out a comparative assessment of 4 types of lithium-ion battery technologies, selected as the most promising technologies being developed across the world. The 4 types of positive electrode materials having been selected are :
Lithium Nickel Manganese Cobalt (NMC)
Lithium Manganese oxide - NCA blend (LMO-NCA or LMO-b)
Lithium Iron Phosphate (LFP)
Lithium Nickel Cobalt Aluminium (NCA)
NCA is the current mainstream manufacturing technology used by SAFT and was therefore regarded as the base case against which the other 3 technologies are compared in the project.
The work achieved from laboratory testing and other analysis of full sized battery to determine the performance, cycle life and storage life, safety under abuse conditions, volume cost and recycling capability.
Seven dedicated Work Packages (WP) were focused on the key tasks, namely :
- WP2 - Ageing analysis, post mortem analysis
- WP3 - Cell specification and test procedures
- WP4 - High energy cell manufacture
- WP5 - Electrical performance testing (cycling and storage)
- WP6 - Safety and abuse testing
- WP7 - Economical assessment
- WP8 - Recycling assessment
-
See figure 1 : technical architecture of Helios project per work package
(all the figures are included in the pdf file)
WP2 Ageing Analysis and Interpretation of Results
The main objective of WP2 is the post-mortem analysis of the 40 Ah cells produced by SAFT. The first WP2 objective was focused on a full bibliographic review on ageing mechanism [4] covered more than 200 references. The potential ageing failure mechanisms for the 4 cathodes chemistries (taking into account the operating conditions : cycling capacity, discharge rates, SOC, Temperature, Upper and Lower voltages) has been achieved. This was also helpful, to set up the different protocols for studying ageing mechanisms which will be undertaken in the different partner labs (SEM, XRD, XPS measurements, electrochemical testing…). The cells coming from testing institutes (EDF, CEA, ZSW, AIT, RWTH-ISEA & ENEA) were delivered to SAFT for disassembling the electrodes before shipment to WP2 partners.
The characterization of initial, intermediate (6 months) and final samples, as function of chemistry and ageing protocols, were performed. This means a huge amount of work and also remarkable time consuming. Moreover, the difficulties in handling some aged electrodes must be highlighted, because of the bad adhesion of the active material (after cycling) on the current collector (see figure 2).
Figure 2 : photos of electrodes (left : middle, EV 30°C sample- right: end, PHEV 45°C sample)
Figure 3 : SEM (ENEA) of pristine (left panel) and intermediate (right) NMC electrodes
However, main recommendations / results can be emphasized :
• Cells must be opened under protective atmosphere.
• Electrode formulations except for NCA electrode were done in research labs with a lack of optimization. The adhesions of all electrodes except NCA were lousy. This parameter could be improved and optimized from the prototypes to industrial phases
• Adhesion is one of the main ageing mechanisms but it is very difficult to evaluate.
• Dissolution issues with NMC and LFP. Dissolutions are activated by the temperature
• Mn migration from LMO to the NCA particles was observed for the LMO-NCA blend material
• The graphite is the limited electrode in the 4 tested technologies.
WP3 Specification of Cells and Test Procedures.
The first objective of the WP3 was to provide a target specification for a high energy cell suited for EV, PHEV and/or HEV-APU applications. This specification was the basis for the large format cells built by SAFT and tested in WP5 and WP6.The battery system specification which was an interims step for D3.1 was also used as boundary information to estimate the battery system cost .
The OEM’s participating in the HELIOS project provided the vehicle based battery requirements which were also broken down to the cell level.
Cell specifications are applicable to both electric and hybrid electric vehicles.
EV battery specification PHEV & HEV-APU battery specification
Usable energy (kWh) 20 10-12
Peak power (kW) 75 kW (@45 s) 80 kW (@15s)
Life >10y 10-15 y
Voltage (V) 250- 420 250-410
E throughput (kWh) 60 000 50 000
Mass (Kg) 200 120
Volume (L) 125 80
Table1 : Battery specifications (HELIOS recommendation)
EV cell specification PHEV cell specification
Energy (Wh) 250 145
Capacity (Ah) 70 35 - 40
Peak Power (W) 750 W (@ 45s) 900 W (@15s)
P/E ratio 4 7
Mass (Kg) 1.4 0.8
Table 2 : Cell target specification (Helios Deliverable 3.1)
The second objective is the definition of the test protocol for Characterization of cells and Performance, cycle and ageing test procedures, with links to other existing procedures available world-wide (see public Deliverable 3.2)
Figure 4: Overview of applicable test profiles
Although, the HELIOS cycle life profiles are based on well-established USABC and ISO standards, it remained the question on how they correlate to real world driving.
As a final step it was planned to compare the HELIOS test cycles with the real life cycle profiles (Artemis urban cycle and US06 highwaycycle) based on the computer simulation of the battery power profile for PHEV / EV vehicles. It was possible to predict the potential mileage of a vehicle with a battery using the cells manufactured within WP4. The simulation showed a good correlation of the HELIOS test procedures with real world operation.
Finally, the third objective was to define Safety test procedures for performance under electrical/thermal/mechanical accident or abuse for new and aged cells. The HELIOS document is based on USABC / Sandia 2005 3123 since this procedure contains all abuse tests to be applied in HELIOS. The EUCAR Hazardous levels are applied. The test procedures define mechanical, thermal and electrical abuse tests for new and pre-aged cells (see public Deliverable 3.3) and were used by WP6.
WP4 Cell Manufacture
The objective of the project was the identification of capable Lithium-Ion technologies for the use in Electric Vehicles (EVs) or in Plug-In-Hybrid Electric Vehicles (PHEV). There were four different basic electrochemical systems which were subject of a detailed investigation for their specific capability as a power source for the electric drive train.
• Lithium-Nickel-Cobalt-Aluminium-Oxide / Graphite (NCA/C)
• Nickel-Manganese-Cobalt –Oxide / Graphite (NMC/C)
• Lithium-Iron-Phosphate / Graphite / (LFP/C)
• Lithium Manganese Oxide (Spinel) / Graphite (LMO/C)
The final goal of the investigation was to benchmark the properties of these different electrochemical systems against each other and to identify their advantages, disadvantages, risks, challenges. From the results a recommendation for the future work on electrochemical system was expected. Besides that, the cost impact for a larger battery production for vehicles (EVs and PHEVs) had to be worked out. Finally, also recycling and material recovery aspects had to be considered for assessing the sustainability of the battery concepts.
Approach
The final investigation of the properties of the electrochemical systems was carried out at full size cells as are already used these days as the basic unit for a battery in vehicle. The cell size selected for that purpose was a cylindrical cell with a diameter of 53mm and a length of 220mm (commercial design used by SAFT Batteries & Johnson Controls).
Before starting with the manufacturing of large cells, the material properties had to undergo a pre-assessment in small cells with approx. 0.5Ah. The results obtained from these pre-investigations were the basis for the later manufacturing of the larger cells. Besides performance characterization the general safety and abuse tolerance properties and features were investigated at the small cells using the different electrochemical electrode combinations. Purpose of the safety related tests was to learn about technologies in general and to be prepared for the later safety tests with the large cells.
Characterization of materials
Materials investigation and single electrode characterization was mainly done by the scientific and technical institutes. This concerned the identification of the best and mostly suitable active electrode materials from various manufacturers all over the world. They also worked out the specific formulations and the recipes of the slurries which were to be used for the electrode coating (Figure 5). In various iterations steps the recipes and the way of the slurry preparation had to be adapted for finally becoming applicable for the industrial pilot line equipment at SAFT.
Figure 5 Preparation of electrode material for later characterization of materials (example for NMC cathodes)
Manufacturing of small cells and pre-investigation
The newly developed electrode materials were used for manufacturing small sample cells based on a cylindrical cell shape (4/5 format). Capacity of the cells was less than 0.5Ah. The investigation carried out at these small cells delivered the expected information. The nickel based chemistry (NCA & NMC) already showed their performance advantage over the LFP-based and the LMO-based chemistry. Physical tests demonstrated the particular challenges of the various electrochemical systems with respect to abuse tolerance and safety.
Manufacturing of large cells and their investigation
For the manufacturing of the large format cells (Figure 6) industrial pilot scale equipment at the SAFT facility in Bordeaux (Figure 7) was used. The cylindrical cells to be manufactured by using the new electrode materials from the project were based on the design of an already existing cylindrical cell.
When using the reference NCA cathode technology the commercial cell has a typical capacity of 41Ah. The NCA based cell was serving as the benchmark system to the cells with the alternative electrochemistry. The cell case design provides a so called Current Interrupt Device (CID) which in case of a detrimental internal pressure vents the cell and releases gases being evolved under abusive conditions. It simultaneously leads to an interrupt of the current and prevents the further operation of the cell.
Figure 6 Cell housing (40Ah) Figure 7 : Picture of 40Ah cells (NCA chemistry)
provided by SAFT and undergoing calendar life tests
About 60 large cells per chemistry were manufactured by SAFT (on industrial pilot line). The recipe of the positive electrode defined previously by labs was adapted and SAFT used the same negative electrode (graphite) and electrolyte for the all 4 chemistries (as proven at NCA cells)
The cells were then sent to WP5, WP6 and WP8 partners to perform abuse and cycling tests.
WP5 Cell Characterisation Test
The work planned was to evaluate high energy lithium-ion cells ageing when submitted to electrical cycling as well as to calendar storage ageing at two temperatures, respectively at 30 & 45°C for electrical tests and at 45°C and 60°C for storage tests.
Within the same cylindrical container (same dimensions, same weight roughly 1 kg and same hardware technologies), the four chemistries prepared have finally different nominal capacity :
NCA NMC LMOb LFP
Capacity selected (Ah) 41 38 28 35
Table 3 : real capacity measured for each technology
Cycling of these cells was performed using the two cycle types defined in WP3 (see also the public deliverable 3.2).
The results expressed in terms of nominal cycles obtained showed that NCA gave the best results with respectively 850-1100 cycles (EV) at 30°C and 45°C and 800-1400 cycles (PHEV). In the same conditions we obtained 400-550 cycles (EV) and 450-500 cycles (PHEV) for NMC while we obtained only 300-350 cycles (EV) and 250-400 cycles (PHEV) for LFP. For LMO-NCA blend cells we obtained at 30°C very good results with 800 nominal cycles (EV) & 850 nominal cycles (PHEV); but their performances are lower by far at 45°C (350-500 nominal cycles) due likely to temperature impact on LMO.
Figure 8 : Capacity decrease for the four chemistries tested in Helios project according EV & PHEV cycling @ 30 and 45°C)
Concerning calendar ageing, the ageing is quite limited, even at the temperature of 60°C. Capacity losses when cells were stored completely charged (SOC100) at 45°C, were of about 5% (NCA), 15% (NMC) and 30% (LMOb) after 10 months, while it was of 30% (LFP) after 6 months. At 60°C, these losses were of about 10% (NCA), 30% (NMC & LMOb) after 10 months, while it was of more than 50% for LFP cells after 6 months. LMO-NCA blend cells stored at SOC 20% showed capacity losses of about 50% at 45°C and 60 to 70% when stored at 60°C (LMO dissolution at low SOCs and high temperature).
Figure 9 : Comparison of the capacity decrease in function of the number of weeks for the four chemistries tested in Helios project and for four cycling test conditions (PHEV, EV cycling @ 45°C and calendar life @ 45 and 60°C)
These results show that in our conditions of test, submitting these cells to electrical cycles (EV or PHEV) is the most constraining parameter concerning the cell capacity decrease, and to a less extent concerning the cells power ability decrease. Moreover, temperature seemed to be a really predominant parameter influencing the cells characteristics, though its influence turned out to be more and more important from storage to EV-Cycling and finally PHEV cycling.
WP6 Safety Test
The main objective of the WP6 task consists in the evaluation of high energy cells in abuse conditions. The safety tests have been performed on 40Ah cells produced by SAFT in 4 versions of different chemistries. The safety of operation is a key point to allow lithium-ion batteries technology to be widely used for electric vehicles. According to the several types of positive active material dealing in the HELIOS project, each of them has not exactly the same performances in terms of specific energy, cycling life time and safety.
A review on the chemical runaway mechanism under abuse conditions (in term of safety) has been established before to perform the tests and to evaluate these various types of lithium-ion batteries.
After running the tests on materials and 0.5 Ah cells, abusive tests were performed on 40 Ah cells (with new and pre-aged). See hereafter the synthesis of the results (figure 10)
Figure 10 : Safety tests results for the four chemistries tested in Helios project according Helios level acceptability for new and pre-aged cells
The three tested technologies could be ranked from the one with the safest behaviour to the lowest as below:
LFP (110Wh) ≥ NMC (140Wh) > NCA (150Wh)
This ranking is rather close than the one obtained on small cell (NMC ≥ LFP > NCA) and the same obtained after DSC measurements on pristine and charged materials.
Regarding the abuse tests on 40 Ah module (without taking into account LMO NCA blend of which capacity is about 28 Ah instead of 40 Ah), crush tests (radial position), nail penetration, short-circuit, thermal stability and overcharge seem to be the most constraining tests.
No technology has a satisfactory behaviour regarding the Helios and Sandia acceptability levels if we consider all the test results at cell level: without BMS (Battery Management System) or casing integration... The elevated temperature storage, overdischarge and thermal shock cycling tests results are similar for all technologies and the corresponding hazard level observed is lower than level acceptability.
WP7 Economical Assessment
The final objective of the work package 7 is to show the price sensitivity on the battery pack considering every electrochemistry studied in the scope of this project for Electric Vehicle &Plug-in Hybrid Electric Vehicle applications.
The 3 scenarii studied are the following :
- Low quantity level : active materials quantity equivalent to 50 000 systems (PHEV or EV) produced per year
- Mid quantity level : active materials quantity equivalent to 100 000 systems (PHEV or EV) produced per year
- High quantity level : active materials quantity equivalent to 200 000 systems (PHEV or EV) produced per year.
The assumption was done that up to 200 000 systems, there’s no significative scale factor.
This study is based on information received by different component suppliers, via a RFI (Request For Information) for all the components of the cells (positive & negative active material, carbon black, binders, positive & negative current collectors, separator, Electrolyte)
For the casing of the cell and pack costs, we’ve applied the model BatPaC developed by Argonne.
The quotation at the system level is obtained from the cost at the cell level, by applying also the Bat PaC tool developed by Argonne (http://www.cse.anl.gov/BatPaC/download.php) considering the number of cells constituting the system for each electrochemistry, for each application (EV, PHEV), and for the three hypotheses of quantity per year.
Concerning active materials of the positive electrode, the results of the study ($/kg) show that:
- NCA is the most expensive material (due to the presence of nickel and cobalt and cost processing) ,
- NMC is between 20 and 25% less expensive than NCA,
- LFP is between 15 and 35% less expensive than NCA for “low” volumes 2000 t/an and until almost 40% less expensive for higher volumes (8000t/an).
- LMO-NCA blend is the cheapest material (45% less expensive). For the graphite (material of negative electrode), the price of artificial graphite is roughly twice the price of a natural graphite, even a surface coated one.
To determine the quantities needed, we used the decomposition in mass, provided by Saft, based on formulations proposed by labs (WP4) to manufacture NMC/C, LMO-NCA/C, LFP/C and NCA/C cells tested in the program. The active material ratio was quite low: NMC (87%) and LFP (90.5%). The LMO-NCA blend with only 85 % of active material, has a specific energy about 90mAh/g, so, it was difficult to have an element of 40Ah. The loading should have been increased of about 35/40 % but, the cells would not have enough power to be tested under PHEV conditions. The optimization under process conditions was not possible in the very strained planning.
The cell case used is the standard case of the NCA/C 41Ah manufactured by SAFT but the capacities obtained are very different for the 4 electrochemical systems (NCA/C : 41Ah, NMC/C : 37 Ah, LFP/C : 35Ah, LMO-NCA/C: 27Ah). To have a more reliable base of comparison, we brought back all technologies with 40 Ah (mass of the raw materials calculated by the BatPaC tool and price of the raw materials obtained from the suppliers in Helios).
This study shows that for the four electrochemical systems, the cell price decreases by approximately 10% while passing from 50000 to 200000 Packs/year for EV application and from 15 to 18% for PHEV application. The costs of the NCA/C, NMC/C, LMO-NCA/C cells are very close:
- For 200,000 EV systems per year, the cost is approximately 140$/kWh for the NCA/C, NMC/C and LMO-NCA/C cells, and approximately 160$/kWh for the LFP/C cell.
- For 200,000 PHEV systems per year, the cost is approximately 250 $/kWh for the NMC/C cell and 260$/kWh for the NCA/C and the LMO-NCA/C cells. LFP/C Cell is the most expensive with approximately 300 $/kWh.
As for the economic evaluation on cell level, we used the Argonne tool (BatPaC) to estimate the cost of the system. To facilitate the comparison, we considered theoretical capacity of 40Ah for PHEV application and 70Ah for EV application
We can conclude that in the case of Helios project :
• For 200 000 Packs/an,
o EV application : the cost varies between 250 and 280 $/kWh
o PHEV application : the cost varies between 310 and 350 $/kWh
• LMO/NCA and NMC are the best candidates on economical point of view. The cost assessment ($/kWh) has the same ranking for PHEV or EV applications: LFP > NCA > LMO/NCA ~ NMC.
• For PHEV application, LFP and NCA technologies are respectively 14% and 8% more expensive than LMO/NCA blend or NMC technologies. For EV application, LFP and NCA technologies are respectively 13% and 6% more expensive than LMO/NCA blend or NMC technologies.
• Comparing EV and PHEV Packs, for an energy almost doubled (14 kWh for PHEV and 26 kWh for EV), the price ($/kWh) is reduced of 25% for the EV pack. The part of materials is higher but the part of Pack integration (BMS, disconnects, cooling if needed) is reduced for EV pack.
• Even if we ‘ve taken into account the cooling systems to improve safety issues for NMC and NCA technologies, NMC is still a very competitive technology.
• NCA (LiNi0.8Co0.15Al0.05O2) which has the best energy density is more expensive at material scale (due to its high content of Nickel but it’s less sensitive to Co-price fluctuation than NMC (LiNi1/3Mn1/3Co 1/3O2). Particularly the NMC and NCA based cells are requiring an efficient recycling.
• Cost for energy storage based on the use of LFP material is the highest for EV and PHEV application (+15%). If we consider the costs in $/kWh or total cost, at material, cell and pack levels. The LFP cost could be lower by reducing the porosity of the raw material. (In the elaboration of cells in Helios project, the porosity of LFP material is quite high, ~50%, and could be reduced), and the cost of processing.
• In the literature we found various estimations made by consultants: the cost estimation in the Anderman’s study appears rather conservative: ~340 – 450 $/kWh for a 24kWh Pack battery for 100,000 units a year. For the same quantity, the Helios study shows a cost between 260 – 300 $/kWh.
On another side, the consultant Roland Berger considers a price of 180-200 €/kWh (237-264 $/kWh) for 2015, for a Pack for energy application, in serie. This estimation is quite low compared to the Helios estimation (250-280$/kWh) but seems more realistic than that of Anderman.
Figure 11 : Cost estimation ($/kWh) at pack level for PHEV 40 Ah cells for the four chemistries tested in Helios project
At pack level (in $/kWh) for PHEV application (see fig 11):
LFP >NCA > LMO/NCA ~ NMC
Figure 12 : Cost estimation ($/kWh) at pack level for EV 70 Ah cells for the four chemistries tested in Helios project
At pack level (in $/kWh) for EV application (see fig 12): LFP >NCA > LMO/NCA ~ NMC
WP8 Recycling Feasibility
The Objectives of WP8 are to identify potential recycling processes guided by their technical feasibility and respective possible output products, to validate experimentally and to estimate the environmental impact and costs of the selected recycling concepts for each technology studied at cell and then at pack levels.
Four potential recycling concepts (see. Figure 13) were identified related to achievable recycling efficiency, productivity, environmental impact, costs and market needs for products coming from hybrid-electric battery (H-EV) recycling processes
Figure 13: Schematic overview of the different recycling concepts described in the WP8 (Concept 2 has not been chosen for safety reasons)
In concept 1, spent cells of Lithium Ion Battery – (LiB) from (H)EV applications are directly treated in a furnace at temperatures above 1500 °C. All organic components of the cells burn or reduce metal oxides like Co, Ni, Fe and Mn. The metallic Al from the casings and the conductor foils burn exothermally and add to the formed slag. Li is mainly slaged. The multi-alloy containing Co, Ni, Mn, Fe and Cu is, because of its complexity, not sellable and needs therefore further hydrometallurgical treatment. The alloy is leached and each metal is selectively precipitated or via solvent extraction separated. At the end high purity metal salts are gained.
To propose the suitable recycling process, RWTH-IME manages recycling trials follow the concepts 3a and 3b. Four types of batteries NCA, NMC, NCA and LFP originating from the Helios consortium are treated. Each battery cell was treated in a resistant furnace at 500 °C, which is connected to the exhaust system of the IME and was flooded by a cover gas (Argon). The mass balance results shows that an average 22% of weight loses are evaluated because of the volatile organic compounds (VOC) originating from the electrolyte, separator and binder.
After pyrolysis the cells were manually dismantled (see figure 14). The cells were separated into the fractions Al casings including pins, Cu foil, Al foil and fine electrode material. In some cases the electrode material reacted during pyrolysis with the Al-Foil. Then the electrode material was difficult to separate from the Al foil because it was melted to the foil or the foil became so thin and brittle that it crumbled away in lots of small pieces just by touching it. In those cases the Al content went almost completely into the fine fraction.
Figure 14: Dismantling steps: Al-Foil, Cu-Foil, Separated electrode material
The pyrometallurgical treatment (3a) of the fine fraction is done in a submerged electric arc furnace. To find a good slag system, which have a low solubility for Li-oxide and still have a good performance with a Ni-Co-Mn-alloy, Li-solubility test and equilibrium tests have been conducted. The slag achieves good results at an electric arc furnace treatment step.
In the hydrometallurgical route (3b), a hydrometallurgical recycling process has been designed and investigated to recover valuable metals from fine fraction. The feasibility of recycling of pure graphite from fine fraction has been investigated. The best efficiency was achieved as Co: 99.9%, Cu: 99.9%, Li: 99.5%, Ni: 99.9%.(s. Figure 15)
Figure 15. Effect of acid kind and oxidizing agent on the leaching of Co, Cu, Li and Ni from electrodes of Li-ion batteries ([HCl]=4 mol/L, [H2SO4]=2mol/L, [H2O2]=50 g/L, T=80 ˚C, S/L=100 g/L, t=2h,rotation speed=300rmp).
A comparison between 3a and 3b has been implemented (Table 4). The different criteria have been selected. The hydrometallurgical process has higher selectivity and less Offgas and energy consumption than pyrometallurgy. However, it has also some disadvantages, such as low space-time yield, high water demand, high additive consumption.
Table 4 : Comparison of hydro and pyro process for EV batteries
(++ = positive impact; -- = negative impact.)
In summary, several possible recycling processes for electric vehicle batteries have been successfully developed. The feasibility of them was estimated by comparing their advantages and disadvantages in aspect of process selectivity, safety, efficiency and possible products. The most suitable recycling concepts 3a and 3b are experimentally validated. The important experimental methods and parameters have been investigated and discussed. Additionally a risk analysis was made for the concepts 3a and 3b. According to the risk analysis the pyrolysis of Li-Ion battery cells affords safety measures to reduce the probability or the severity of possible toxic gas emissions. The recycling efficiency (RE) calculation shows that all three recycling concepts, 1, 3a and 3b, meet the RE-target of 50% imposed by the EU-Directive 2006/66/EC.
To identify the extra needs when scaling up from single cells to modules and finally to the entire battery pack, all elements of (H)EV battery recycling processes must be considered in order to assure optimal balance between the relevant societal, economic and environmental sustainability pillars, therefore a fishbone diagram is designed and presented below (Figure 16).
Figure 16 : Fishbone Diagram Illustrating the Different Aspects of Battery Recycling
Possible motivations for a partial (or complete) disassembly are presented:
• Technical: It is a technical challenge to introduce battery packs up to 400 kg to the proposed recycling schemes (material handling and equipment sizing implications). However, future large scale facilities should be designed to handle at least up to 200kg battery packs.
• Environmental: The auxiliary elements include relatively pure fractions (steel, Al, Cu) that don’t need complex metallurgical processing. An up-front removal/separation of these parts creates some financial burden but, depending on the recycling process used, may deliver also some environmental credits (downstream processing simplified)
• Economic: Trade-off exists between the dismantling costs (operator time) and higher processing costs (equipment).
EV battery recycling is a combination of pre-treatment and metallurgical and chemical processes; the optimum combination depends on many variables (volume, battery chemistry and assembly design, investment and labour cost, ).
Conclusion and perspectives :
The project is showing significant information on the differences between the 4 cell technologies. This will provide considerable assistance to future R&D and industrial developments and give a good overview of the most used Li-ion technologies.
The main results, conclusions obtained within Helios project can be summarized in the table 7:
Table 7 : Overview and synthesis of Helios results
In conclusion, no technology presents the best features on performances, safety, economical and recycling points of view. Compromises must be done to do the best choice according the application and the technology selected.
However, we can emphasize that NMC based cells showed a slightly lower capacity than the NCA based cells, but continued material improvement and further adaptations in the cell geometry may lead to an equivalent energy density to the current NCA product. LMO/NCA-blend cells are definitely significantly lower in their capacity. Future activities with respect to an optimization in the mass mixture and the recipe may lead to at least partly compensate this disadvantage. Results with LFP based cells selected in Helios project were rather disappointing, particularly with regard to life endurance but it is expected that optimization with this chemistry and the improvement of the moisture content specification of raw material will overcome the life problem. Also the capacity of these cells may be further increased without sacrificing their advantageous abuse tolerance. This makes them interesting especially for those PHEVs with a relatively small battery system.
Potential Impact:
The reduction of emissions (CO2, particles …) in the atmosphere is THE challenge of the next decades. The development of electric and Hybrid vehicles will deeply contribute to this objective and to fulfil the CAFE target (Corporate Average Fuel Economy) which is 95 g CO2/Km end 2020.
High level of knowledge and good collaboration between the main actors (car and batteries manufacturers, energy holders but also R&D laboratories) are the key of the success of this development.
By achieving and evaluating new, safer, more efficient and cheaper Li-ion cells, HELIOS will contribute to an enhanced use of low or zero emission vehicles, which will provides citizens better health and better quality of life.
Impact on European Research :
The main objective of Helios project is to gather European car manufacturers, battery manufacturers, research organisations and recyclers with their interdisciplinary skills in order to form a strong collaboration, to generate new knowledge and recommendations that will be implemented in future products.
Six European OEMs, who are the main end-users, were deeply involved in the consortium. Furthermore, there were a very good complementarity and fruitful interaction between partners (industrials, universities, R&D labs and technical Centers).
Scientific and technological impacts and reinforcing European competitiveness :
The comparisons covered in Helios project will be a good support to the automotive industry, research organisations and legislative bodies in their decision making for the future development of electric and hybrid electric vehicles :
- For the end users, having tests procedures for safety and electrical tests, robust and agreed
- Ageing model will give a helpful tool to define the ageing mechanisms
- Selection and evaluation of the most- promising positive electrode materials on safety, performance and economical points of view.
Finally, we can conclude that each of the four Li-ion chemistries have some advantages / disadvantages / risks and opportunities. A compromise has to be done according the technology and the application chosen.
Main Dissemination activities :
The Dissemination activities were conducted throughout the project, from the first year and will go on during the next months to disseminate all the results.
Within the EUCAR organisation, yearly presentation were explained and discussed during the EUCAR program board meetings. A poster was also established and presented during the four last EUCAR conferences. Furthermore, the test procedures developed in the WP3 were introduced and promoted in the Working Group EUCAR dedicated to Battery eVs, and fuel cells eV.
Throughout all the duration of the project, there was a large involvement of the coordinator in seminars & workshop organized by the Green Car Initiative (July, Nov 2012 and April 2013). It was an opportunity to present and share Helios’s results and experience with industry, scientific community and the European commission. These meetings promote also widely the dissemination and the sharing between the European projects.
Several papers and talks were also presented in International conferences by Helios partners (batteries 2012, EVS 26 & 27, IWIS …)
The results of Helios will continue to be largely disseminated to a wide community via scientific presentations and dissemination via the public web site and via distribution of the twenty deliverables with Restricted dissemination to selected beneficiaries (scientific community, experts, other FP7 projects …).
-HELIOS provides tests procedures to carry out safety and electrical tests within the project but they can be widely used by similar testing activities. The deliverables are public reports, they are available on the Helios website and they were presented to EUCAR experts working group. The procedures have been also shared with other European projects (ELIBAMA, EUROLIION, AMELIE, EASYBAT …) :
- Cell specifications applicable to both electric and hybrid electric vehicles (see public Deliverable 3.1)
- Performance, cycle and ageing test procedures, with links to other existing procedures available world-wide and characterisation of the cells (see public Deliverable 3.2)
- Safety test procedures for performance under electrical/thermal/mechanical accident or abuse for new and aged cells (see public Deliverable 3.3)
- post-mortem analysis performed in the WP2 are confidential. But an abstract of the deliverable 2.5 resuming the interpretation of the ageing results measured on Helios cells (on electrodes, separators and electrolyte) will be uploaded on the Helios public website to benefit to the scientific community and R&D labs. Based on their experiences, some recommendations were also emphasized to select the right analysis methods and to prepare and handle the samples. In particular, for post-mortem analysis it is important to open the cell under protective atmosphere to avoid any contact with air and moisture and generate “parasite” reactions.
-Development of Procedures and recommendation for handling of used cells and recovery of materials during recycling process (see Deliverables 8.1 8.2 & 8.3) taken into account economical, Life Cycle Assessment and safety points of view were established. They describe and compare the main process and the best practises. These deliverables have been sent to RECHARGE and EBRA (European Battery Recycling Association) and to EUROLIION project.
-Economical assessment at material, cell and pack level will be also shared with other FP7 projects (AMELIE, EUROLIION…). A specific report, resuming the main results described in the deliverables 7.1 7.2 and 7.3 has been consolidated and will be sent to main suppliers and shared with other battery’s projects (EUROLIION, AMELIE, ELIBAMA …).
List of Websites:
website : http://www.helios-eu.org/
coordinator : RENAULT – Frédérique Del Corso – Frederique.delcorso@renault.com - 1 av du golf- API TCR LAB 0 12 - 78084 Guyancourt- France
WP leaders :
ADAM OPEL AG, Russelsheim – Germany,
CNRS-LRCS, 80039 Amiens – France
JCHaR, 30419 Hannover, Germany,
SAFT, 33074 Bordeaux – France,
EDF, 77818 Moret/ Loing – France,
INERIS, 60550 Verneuil / Halatte – France,
PSA , 78955 Carrières sous Poissy- France,
RWTH-IME, D 52056 Aachen - Germany
HELIOS consortium : 18 partners are involved from 6 european countries
Battery reliability and safety are the key issue for the commercialization of x-EV vehicles, especially for High Energy applications, requiring a large amount of energy stored on board.
HELIOS is a 4 year project to carry out a comparative assessment of 4 types of lithium-ion battery technologies, selected as the most promising technologies being developed across the world: NCA, NMC, LMO & LFP/C. The assessments concern traction batteries for the automotive sector (EV, PHEV & HEV-APU). The work achieved from laboratory testing and other analysis deliver the comparative data covering performance, life, cost, recycling and safety/abuse characteristics.
NCA is the current mainstream manufacturing technology used by SAFT and is therefore the base case against which the other 3 technologies are compared using the same design, same electrolyte and same electrode material. In each case the evaluations are carried out on representative size high energy cells (with a capacity of approximately 40 Ah), produced industrially. In total, up to 220 cells have been employed across the various test activities (safety tests on new and pre-aged cells), cycling (EV and PHEV) and calendar tests (12-15 months).
Post-mortem analysis were also performed at 3 different ageing steps (0, 6 and 12/15 months). The main objective, and not the less, is to evaluate the impact of the cell characteristics on the ageing mechanisms.
The main conclusion under all the results is that no chemistry fulfil all the requirements on the performance, durability, economical and safety points of view. The alternative systems (to NCA commercial and reference one) provide a potential for further improvement and possible application.
It needs to be emphasized that the cells were not manufactured on an industrial scale. It’s expected that optimization of the design & the formulation will overcome the life duration problems and improve significantly the energy density.
However, all these results will give a stronger knowledge base to develop the future Electric and Hybrid / Plug-In Hybrid electric vehicles by the vehicle OEM’s and the supply industry. The end result will give, to decision makers, a clearer view of the potentially effective investments in research, development and manufacture. Furthermore they will contribute to the development of x-EV vehicles and so, too long term benefits for the environment, fuel security and European Union employment
Project Context and Objectives:
The automobile industry and urban transport operators must meet the required reduction of the environmental impact of vehicles and thereby contribute to the objectives fixed by the EU Climate and Energy package known as the “Grenelle de l'Environnement”20-20-20 targets: 20 % renewables energies by 2020, 20% reduction of CO2 emissions and fuel consumption from transport. Innovative, safe and with high performance energy storage solutions have to be studied and grow up.
Energy storage is an area of rapidly evolving technology. Lithium-ion has become the dominant rechargeable battery chemistry for consumer electronics devices and is going to become also the most competitive technology for industrial, transportation, and power-storage applications. From a technological point of view, this chemistry provides a high specific energy (Wh/kg) and high energy density (Wh/L) regarding previously popular rechargeable battery chemistries (nickel metal hydride, nickel cadmium, and lead acid battery).
Battery reliability and safety are the key issue for the commercialization of x-EV vehicles.
Objectives and presentation of Helios project :
HELIOS is a 4 year project to carry out a comparative assessment of 4 types of lithium-ion battery technologies, selected as the most promising technologies being developed across the world. The 4 types of positive electrode materials having been selected are :
Lithium Nickel Manganese Cobalt (NMC)
Lithium Manganese oxide - NCA blend (LMO-NCA or LMO-b)
Lithium Iron Phosphate (LFP)
Lithium Nickel Cobalt Aluminium (NCA)
NCA is the current mainstream manufacturing technology used by SAFT and regarded therefore as the base case against which the other 3 technologies are compared. In order to make the comparison easier (changing only one thing at a time: the positive electrode material), electrolyte and negative electrode were kept the same, only adjusting quantities (balancing electrodes capacities and electrolyte quantity) to optimize the cell operation.
The assessments concern traction batteries for the automotive sector (EV, PHEV & HEV-APU).
The work achieved from laboratory testing and other analysis of full sized battery to determine the performance, cycle life and storage life, safety under abuse conditions, volume cost, capability for recycling of material.
The majority of the work was performed at cell level, with some module abuse testing (typically 4 cells). In all cases, the comparative results have been extrapolated to full battery pack size units suitable for complete vehicle. From the results, a recommendation for the future work on electrochemical system was proposed.
Main Results :
The final goal of the investigation is to benchmark the properties of the four different electrochemical systems versus each other and to identify their advantages, disadvantages, risks, challenges.
In order to carry out the testing and analysis work it was necessary to develop procedures for each phase. These documents are available for future use in similar activities:
- Cell specifications applicable to both electric and hybrid electric vehicles (see table1 - figures are included in the pdf file)
- Performance, cycle and ageing test procedures, with links to other existing procedures available world-wide (see public Deliverable 3.2)
- Safety test procedures for performance under electrical/thermal/mechanical accident or abuse for new and aged cells (see public Deliverable 3.3)
- Procedures and recommendation for handling of used cells and recovery of materials (see Deliverables 8.1 & 8.2).
- Electrical tests show that EV & PHEV cycles defined in the project are the most constraining parameter (concerning the cell capacity decrease, and cells power ability decrease in a less extent). Moreover, temperature seems to be a really predominant parameter influencing the cells ageing, though its influence turned out to be more and more important from storage to EV-Cycling and finally PHEV cycling (see figure 1: Capacity decrease for the four chemistries tested in Helios project and for four cycling test conditions (PHEV, EV cycling @ 45°C and calendar life @ 45 and 60°C). NCA and NMC cells show the best performances at 30 and 45°C.
- The safety tests have been performed on 40Ah cells produced by SAFT. Safety is the key point to allow lithium-ion batteries technology to be widely used for electric vehicles. According to the several types of positive active material dealing in the HELIOS project, each of them has not exactly the same performances in terms of specific energy, cycling life time and safety. A review on the chemical runaway mechanism under abuse conditions has been performed and disseminated (see the public deliverable 6.1).
Abusive tests were performed on 40 Ah cells (with new and pre-aged cells).
The three tested technologies could be ranked from the one with the safest behaviour to the lowest as below: LFP (110Wh) ≥ NMC (140Wh) > NCA (150Wh)
This ranking is rather close than the one obtained on small cell (NMC ≥ LFP > NCA) and the same obtained after Differential Scanning Calorimetry measurements on pristine and charged materials.
Regarding the abuse tests on 40 Ah module (without taking into account LMO NCA blend of which capacity is about 28 Ah instead of 40 Ah), crush tests (radial position), nail penetration, short-circuit, thermal stability and overcharge seem to be the most constraining tests.
No technology has a satisfactory behaviour if we consider all the test results at cell level: without BMS (Battery Management System) or casing integration...
- Finally, post-mortem analysis on new, intermediate and final samples showed that :
- Adhesion is one of the main ageing mechanism (but electrode formulations except for NCA were done by labs with low optimisation)
- Dissolution issue with NMC and LFP is activated by the temperature
- Graphite is the limited electrode for the 4 technologies
- for LMO-NCA / Graphite cells, a Mn migration was observed from LMO to NCA particles.
Conclusion and perspectives :
The project is showing significant information on the differences between the 4 cell technologies. This will provide considerable assistance to future R&D and business decision making within the industry. The main results, conclusions obtained within Helios project can be summarized in the table 2 (Overview and synthesis of Helios results).
The NMC based cells showed a slightly lower capacity than the NCA based cells, but continued material improvement and further adaptations in the cell geometry may lead to an equivalent energy density to the current NCA product. LMO/NCA-blend cells are definitely significantly lower in their capacity. Future activities with respect to an optimization in the mass mixture and the recipe may lead to at least partly compensate this disadvantage. LFP based cells were rather disappointing, particularly with regard to life endurance, linked to water content of positive material electrode (water content of raw material, and many transportation steps). It needs to be emphasized that the cells were not manufactured on an industrial scale. It is expected that optimization with this chemistry will overcome the life problem. Also the capacity of these cells may be further increased without sacrificing their advantageous abuse tolerance. This makes them interesting especially for those PHEVs with a relatively small battery system.
Project Results:
HELIOS is a 4 year project to carry out a comparative assessment of 4 types of lithium-ion battery technologies, selected as the most promising technologies being developed across the world. The 4 types of positive electrode materials having been selected are :
Lithium Nickel Manganese Cobalt (NMC)
Lithium Manganese oxide - NCA blend (LMO-NCA or LMO-b)
Lithium Iron Phosphate (LFP)
Lithium Nickel Cobalt Aluminium (NCA)
NCA is the current mainstream manufacturing technology used by SAFT and was therefore regarded as the base case against which the other 3 technologies are compared in the project.
The work achieved from laboratory testing and other analysis of full sized battery to determine the performance, cycle life and storage life, safety under abuse conditions, volume cost and recycling capability.
Seven dedicated Work Packages (WP) were focused on the key tasks, namely :
- WP2 - Ageing analysis, post mortem analysis
- WP3 - Cell specification and test procedures
- WP4 - High energy cell manufacture
- WP5 - Electrical performance testing (cycling and storage)
- WP6 - Safety and abuse testing
- WP7 - Economical assessment
- WP8 - Recycling assessment
-
See figure 1 : technical architecture of Helios project per work package
(all the figures are included in the pdf file)
WP2 Ageing Analysis and Interpretation of Results
The main objective of WP2 is the post-mortem analysis of the 40 Ah cells produced by SAFT. The first WP2 objective was focused on a full bibliographic review on ageing mechanism [4] covered more than 200 references. The potential ageing failure mechanisms for the 4 cathodes chemistries (taking into account the operating conditions : cycling capacity, discharge rates, SOC, Temperature, Upper and Lower voltages) has been achieved. This was also helpful, to set up the different protocols for studying ageing mechanisms which will be undertaken in the different partner labs (SEM, XRD, XPS measurements, electrochemical testing…). The cells coming from testing institutes (EDF, CEA, ZSW, AIT, RWTH-ISEA & ENEA) were delivered to SAFT for disassembling the electrodes before shipment to WP2 partners.
The characterization of initial, intermediate (6 months) and final samples, as function of chemistry and ageing protocols, were performed. This means a huge amount of work and also remarkable time consuming. Moreover, the difficulties in handling some aged electrodes must be highlighted, because of the bad adhesion of the active material (after cycling) on the current collector (see figure 2).
Figure 2 : photos of electrodes (left : middle, EV 30°C sample- right: end, PHEV 45°C sample)
Figure 3 : SEM (ENEA) of pristine (left panel) and intermediate (right) NMC electrodes
However, main recommendations / results can be emphasized :
• Cells must be opened under protective atmosphere.
• Electrode formulations except for NCA electrode were done in research labs with a lack of optimization. The adhesions of all electrodes except NCA were lousy. This parameter could be improved and optimized from the prototypes to industrial phases
• Adhesion is one of the main ageing mechanisms but it is very difficult to evaluate.
• Dissolution issues with NMC and LFP. Dissolutions are activated by the temperature
• Mn migration from LMO to the NCA particles was observed for the LMO-NCA blend material
• The graphite is the limited electrode in the 4 tested technologies.
WP3 Specification of Cells and Test Procedures.
The first objective of the WP3 was to provide a target specification for a high energy cell suited for EV, PHEV and/or HEV-APU applications. This specification was the basis for the large format cells built by SAFT and tested in WP5 and WP6.The battery system specification which was an interims step for D3.1 was also used as boundary information to estimate the battery system cost .
The OEM’s participating in the HELIOS project provided the vehicle based battery requirements which were also broken down to the cell level.
Cell specifications are applicable to both electric and hybrid electric vehicles.
EV battery specification PHEV & HEV-APU battery specification
Usable energy (kWh) 20 10-12
Peak power (kW) 75 kW (@45 s) 80 kW (@15s)
Life >10y 10-15 y
Voltage (V) 250- 420 250-410
E throughput (kWh) 60 000 50 000
Mass (Kg) 200 120
Volume (L) 125 80
Table1 : Battery specifications (HELIOS recommendation)
EV cell specification PHEV cell specification
Energy (Wh) 250 145
Capacity (Ah) 70 35 - 40
Peak Power (W) 750 W (@ 45s) 900 W (@15s)
P/E ratio 4 7
Mass (Kg) 1.4 0.8
Table 2 : Cell target specification (Helios Deliverable 3.1)
The second objective is the definition of the test protocol for Characterization of cells and Performance, cycle and ageing test procedures, with links to other existing procedures available world-wide (see public Deliverable 3.2)
Figure 4: Overview of applicable test profiles
Although, the HELIOS cycle life profiles are based on well-established USABC and ISO standards, it remained the question on how they correlate to real world driving.
As a final step it was planned to compare the HELIOS test cycles with the real life cycle profiles (Artemis urban cycle and US06 highwaycycle) based on the computer simulation of the battery power profile for PHEV / EV vehicles. It was possible to predict the potential mileage of a vehicle with a battery using the cells manufactured within WP4. The simulation showed a good correlation of the HELIOS test procedures with real world operation.
Finally, the third objective was to define Safety test procedures for performance under electrical/thermal/mechanical accident or abuse for new and aged cells. The HELIOS document is based on USABC / Sandia 2005 3123 since this procedure contains all abuse tests to be applied in HELIOS. The EUCAR Hazardous levels are applied. The test procedures define mechanical, thermal and electrical abuse tests for new and pre-aged cells (see public Deliverable 3.3) and were used by WP6.
WP4 Cell Manufacture
The objective of the project was the identification of capable Lithium-Ion technologies for the use in Electric Vehicles (EVs) or in Plug-In-Hybrid Electric Vehicles (PHEV). There were four different basic electrochemical systems which were subject of a detailed investigation for their specific capability as a power source for the electric drive train.
• Lithium-Nickel-Cobalt-Aluminium-Oxide / Graphite (NCA/C)
• Nickel-Manganese-Cobalt –Oxide / Graphite (NMC/C)
• Lithium-Iron-Phosphate / Graphite / (LFP/C)
• Lithium Manganese Oxide (Spinel) / Graphite (LMO/C)
The final goal of the investigation was to benchmark the properties of these different electrochemical systems against each other and to identify their advantages, disadvantages, risks, challenges. From the results a recommendation for the future work on electrochemical system was expected. Besides that, the cost impact for a larger battery production for vehicles (EVs and PHEVs) had to be worked out. Finally, also recycling and material recovery aspects had to be considered for assessing the sustainability of the battery concepts.
Approach
The final investigation of the properties of the electrochemical systems was carried out at full size cells as are already used these days as the basic unit for a battery in vehicle. The cell size selected for that purpose was a cylindrical cell with a diameter of 53mm and a length of 220mm (commercial design used by SAFT Batteries & Johnson Controls).
Before starting with the manufacturing of large cells, the material properties had to undergo a pre-assessment in small cells with approx. 0.5Ah. The results obtained from these pre-investigations were the basis for the later manufacturing of the larger cells. Besides performance characterization the general safety and abuse tolerance properties and features were investigated at the small cells using the different electrochemical electrode combinations. Purpose of the safety related tests was to learn about technologies in general and to be prepared for the later safety tests with the large cells.
Characterization of materials
Materials investigation and single electrode characterization was mainly done by the scientific and technical institutes. This concerned the identification of the best and mostly suitable active electrode materials from various manufacturers all over the world. They also worked out the specific formulations and the recipes of the slurries which were to be used for the electrode coating (Figure 5). In various iterations steps the recipes and the way of the slurry preparation had to be adapted for finally becoming applicable for the industrial pilot line equipment at SAFT.
Figure 5 Preparation of electrode material for later characterization of materials (example for NMC cathodes)
Manufacturing of small cells and pre-investigation
The newly developed electrode materials were used for manufacturing small sample cells based on a cylindrical cell shape (4/5 format). Capacity of the cells was less than 0.5Ah. The investigation carried out at these small cells delivered the expected information. The nickel based chemistry (NCA & NMC) already showed their performance advantage over the LFP-based and the LMO-based chemistry. Physical tests demonstrated the particular challenges of the various electrochemical systems with respect to abuse tolerance and safety.
Manufacturing of large cells and their investigation
For the manufacturing of the large format cells (Figure 6) industrial pilot scale equipment at the SAFT facility in Bordeaux (Figure 7) was used. The cylindrical cells to be manufactured by using the new electrode materials from the project were based on the design of an already existing cylindrical cell.
When using the reference NCA cathode technology the commercial cell has a typical capacity of 41Ah. The NCA based cell was serving as the benchmark system to the cells with the alternative electrochemistry. The cell case design provides a so called Current Interrupt Device (CID) which in case of a detrimental internal pressure vents the cell and releases gases being evolved under abusive conditions. It simultaneously leads to an interrupt of the current and prevents the further operation of the cell.
Figure 6 Cell housing (40Ah) Figure 7 : Picture of 40Ah cells (NCA chemistry)
provided by SAFT and undergoing calendar life tests
About 60 large cells per chemistry were manufactured by SAFT (on industrial pilot line). The recipe of the positive electrode defined previously by labs was adapted and SAFT used the same negative electrode (graphite) and electrolyte for the all 4 chemistries (as proven at NCA cells)
The cells were then sent to WP5, WP6 and WP8 partners to perform abuse and cycling tests.
WP5 Cell Characterisation Test
The work planned was to evaluate high energy lithium-ion cells ageing when submitted to electrical cycling as well as to calendar storage ageing at two temperatures, respectively at 30 & 45°C for electrical tests and at 45°C and 60°C for storage tests.
Within the same cylindrical container (same dimensions, same weight roughly 1 kg and same hardware technologies), the four chemistries prepared have finally different nominal capacity :
NCA NMC LMOb LFP
Capacity selected (Ah) 41 38 28 35
Table 3 : real capacity measured for each technology
Cycling of these cells was performed using the two cycle types defined in WP3 (see also the public deliverable 3.2).
The results expressed in terms of nominal cycles obtained showed that NCA gave the best results with respectively 850-1100 cycles (EV) at 30°C and 45°C and 800-1400 cycles (PHEV). In the same conditions we obtained 400-550 cycles (EV) and 450-500 cycles (PHEV) for NMC while we obtained only 300-350 cycles (EV) and 250-400 cycles (PHEV) for LFP. For LMO-NCA blend cells we obtained at 30°C very good results with 800 nominal cycles (EV) & 850 nominal cycles (PHEV); but their performances are lower by far at 45°C (350-500 nominal cycles) due likely to temperature impact on LMO.
Figure 8 : Capacity decrease for the four chemistries tested in Helios project according EV & PHEV cycling @ 30 and 45°C)
Concerning calendar ageing, the ageing is quite limited, even at the temperature of 60°C. Capacity losses when cells were stored completely charged (SOC100) at 45°C, were of about 5% (NCA), 15% (NMC) and 30% (LMOb) after 10 months, while it was of 30% (LFP) after 6 months. At 60°C, these losses were of about 10% (NCA), 30% (NMC & LMOb) after 10 months, while it was of more than 50% for LFP cells after 6 months. LMO-NCA blend cells stored at SOC 20% showed capacity losses of about 50% at 45°C and 60 to 70% when stored at 60°C (LMO dissolution at low SOCs and high temperature).
Figure 9 : Comparison of the capacity decrease in function of the number of weeks for the four chemistries tested in Helios project and for four cycling test conditions (PHEV, EV cycling @ 45°C and calendar life @ 45 and 60°C)
These results show that in our conditions of test, submitting these cells to electrical cycles (EV or PHEV) is the most constraining parameter concerning the cell capacity decrease, and to a less extent concerning the cells power ability decrease. Moreover, temperature seemed to be a really predominant parameter influencing the cells characteristics, though its influence turned out to be more and more important from storage to EV-Cycling and finally PHEV cycling.
WP6 Safety Test
The main objective of the WP6 task consists in the evaluation of high energy cells in abuse conditions. The safety tests have been performed on 40Ah cells produced by SAFT in 4 versions of different chemistries. The safety of operation is a key point to allow lithium-ion batteries technology to be widely used for electric vehicles. According to the several types of positive active material dealing in the HELIOS project, each of them has not exactly the same performances in terms of specific energy, cycling life time and safety.
A review on the chemical runaway mechanism under abuse conditions (in term of safety) has been established before to perform the tests and to evaluate these various types of lithium-ion batteries.
After running the tests on materials and 0.5 Ah cells, abusive tests were performed on 40 Ah cells (with new and pre-aged). See hereafter the synthesis of the results (figure 10)
Figure 10 : Safety tests results for the four chemistries tested in Helios project according Helios level acceptability for new and pre-aged cells
The three tested technologies could be ranked from the one with the safest behaviour to the lowest as below:
LFP (110Wh) ≥ NMC (140Wh) > NCA (150Wh)
This ranking is rather close than the one obtained on small cell (NMC ≥ LFP > NCA) and the same obtained after DSC measurements on pristine and charged materials.
Regarding the abuse tests on 40 Ah module (without taking into account LMO NCA blend of which capacity is about 28 Ah instead of 40 Ah), crush tests (radial position), nail penetration, short-circuit, thermal stability and overcharge seem to be the most constraining tests.
No technology has a satisfactory behaviour regarding the Helios and Sandia acceptability levels if we consider all the test results at cell level: without BMS (Battery Management System) or casing integration... The elevated temperature storage, overdischarge and thermal shock cycling tests results are similar for all technologies and the corresponding hazard level observed is lower than level acceptability.
WP7 Economical Assessment
The final objective of the work package 7 is to show the price sensitivity on the battery pack considering every electrochemistry studied in the scope of this project for Electric Vehicle &Plug-in Hybrid Electric Vehicle applications.
The 3 scenarii studied are the following :
- Low quantity level : active materials quantity equivalent to 50 000 systems (PHEV or EV) produced per year
- Mid quantity level : active materials quantity equivalent to 100 000 systems (PHEV or EV) produced per year
- High quantity level : active materials quantity equivalent to 200 000 systems (PHEV or EV) produced per year.
The assumption was done that up to 200 000 systems, there’s no significative scale factor.
This study is based on information received by different component suppliers, via a RFI (Request For Information) for all the components of the cells (positive & negative active material, carbon black, binders, positive & negative current collectors, separator, Electrolyte)
For the casing of the cell and pack costs, we’ve applied the model BatPaC developed by Argonne.
The quotation at the system level is obtained from the cost at the cell level, by applying also the Bat PaC tool developed by Argonne (http://www.cse.anl.gov/BatPaC/download.php) considering the number of cells constituting the system for each electrochemistry, for each application (EV, PHEV), and for the three hypotheses of quantity per year.
Concerning active materials of the positive electrode, the results of the study ($/kg) show that:
- NCA is the most expensive material (due to the presence of nickel and cobalt and cost processing) ,
- NMC is between 20 and 25% less expensive than NCA,
- LFP is between 15 and 35% less expensive than NCA for “low” volumes 2000 t/an and until almost 40% less expensive for higher volumes (8000t/an).
- LMO-NCA blend is the cheapest material (45% less expensive). For the graphite (material of negative electrode), the price of artificial graphite is roughly twice the price of a natural graphite, even a surface coated one.
To determine the quantities needed, we used the decomposition in mass, provided by Saft, based on formulations proposed by labs (WP4) to manufacture NMC/C, LMO-NCA/C, LFP/C and NCA/C cells tested in the program. The active material ratio was quite low: NMC (87%) and LFP (90.5%). The LMO-NCA blend with only 85 % of active material, has a specific energy about 90mAh/g, so, it was difficult to have an element of 40Ah. The loading should have been increased of about 35/40 % but, the cells would not have enough power to be tested under PHEV conditions. The optimization under process conditions was not possible in the very strained planning.
The cell case used is the standard case of the NCA/C 41Ah manufactured by SAFT but the capacities obtained are very different for the 4 electrochemical systems (NCA/C : 41Ah, NMC/C : 37 Ah, LFP/C : 35Ah, LMO-NCA/C: 27Ah). To have a more reliable base of comparison, we brought back all technologies with 40 Ah (mass of the raw materials calculated by the BatPaC tool and price of the raw materials obtained from the suppliers in Helios).
This study shows that for the four electrochemical systems, the cell price decreases by approximately 10% while passing from 50000 to 200000 Packs/year for EV application and from 15 to 18% for PHEV application. The costs of the NCA/C, NMC/C, LMO-NCA/C cells are very close:
- For 200,000 EV systems per year, the cost is approximately 140$/kWh for the NCA/C, NMC/C and LMO-NCA/C cells, and approximately 160$/kWh for the LFP/C cell.
- For 200,000 PHEV systems per year, the cost is approximately 250 $/kWh for the NMC/C cell and 260$/kWh for the NCA/C and the LMO-NCA/C cells. LFP/C Cell is the most expensive with approximately 300 $/kWh.
As for the economic evaluation on cell level, we used the Argonne tool (BatPaC) to estimate the cost of the system. To facilitate the comparison, we considered theoretical capacity of 40Ah for PHEV application and 70Ah for EV application
We can conclude that in the case of Helios project :
• For 200 000 Packs/an,
o EV application : the cost varies between 250 and 280 $/kWh
o PHEV application : the cost varies between 310 and 350 $/kWh
• LMO/NCA and NMC are the best candidates on economical point of view. The cost assessment ($/kWh) has the same ranking for PHEV or EV applications: LFP > NCA > LMO/NCA ~ NMC.
• For PHEV application, LFP and NCA technologies are respectively 14% and 8% more expensive than LMO/NCA blend or NMC technologies. For EV application, LFP and NCA technologies are respectively 13% and 6% more expensive than LMO/NCA blend or NMC technologies.
• Comparing EV and PHEV Packs, for an energy almost doubled (14 kWh for PHEV and 26 kWh for EV), the price ($/kWh) is reduced of 25% for the EV pack. The part of materials is higher but the part of Pack integration (BMS, disconnects, cooling if needed) is reduced for EV pack.
• Even if we ‘ve taken into account the cooling systems to improve safety issues for NMC and NCA technologies, NMC is still a very competitive technology.
• NCA (LiNi0.8Co0.15Al0.05O2) which has the best energy density is more expensive at material scale (due to its high content of Nickel but it’s less sensitive to Co-price fluctuation than NMC (LiNi1/3Mn1/3Co 1/3O2). Particularly the NMC and NCA based cells are requiring an efficient recycling.
• Cost for energy storage based on the use of LFP material is the highest for EV and PHEV application (+15%). If we consider the costs in $/kWh or total cost, at material, cell and pack levels. The LFP cost could be lower by reducing the porosity of the raw material. (In the elaboration of cells in Helios project, the porosity of LFP material is quite high, ~50%, and could be reduced), and the cost of processing.
• In the literature we found various estimations made by consultants: the cost estimation in the Anderman’s study appears rather conservative: ~340 – 450 $/kWh for a 24kWh Pack battery for 100,000 units a year. For the same quantity, the Helios study shows a cost between 260 – 300 $/kWh.
On another side, the consultant Roland Berger considers a price of 180-200 €/kWh (237-264 $/kWh) for 2015, for a Pack for energy application, in serie. This estimation is quite low compared to the Helios estimation (250-280$/kWh) but seems more realistic than that of Anderman.
Figure 11 : Cost estimation ($/kWh) at pack level for PHEV 40 Ah cells for the four chemistries tested in Helios project
At pack level (in $/kWh) for PHEV application (see fig 11):
LFP >NCA > LMO/NCA ~ NMC
Figure 12 : Cost estimation ($/kWh) at pack level for EV 70 Ah cells for the four chemistries tested in Helios project
At pack level (in $/kWh) for EV application (see fig 12): LFP >NCA > LMO/NCA ~ NMC
WP8 Recycling Feasibility
The Objectives of WP8 are to identify potential recycling processes guided by their technical feasibility and respective possible output products, to validate experimentally and to estimate the environmental impact and costs of the selected recycling concepts for each technology studied at cell and then at pack levels.
Four potential recycling concepts (see. Figure 13) were identified related to achievable recycling efficiency, productivity, environmental impact, costs and market needs for products coming from hybrid-electric battery (H-EV) recycling processes
Figure 13: Schematic overview of the different recycling concepts described in the WP8 (Concept 2 has not been chosen for safety reasons)
In concept 1, spent cells of Lithium Ion Battery – (LiB) from (H)EV applications are directly treated in a furnace at temperatures above 1500 °C. All organic components of the cells burn or reduce metal oxides like Co, Ni, Fe and Mn. The metallic Al from the casings and the conductor foils burn exothermally and add to the formed slag. Li is mainly slaged. The multi-alloy containing Co, Ni, Mn, Fe and Cu is, because of its complexity, not sellable and needs therefore further hydrometallurgical treatment. The alloy is leached and each metal is selectively precipitated or via solvent extraction separated. At the end high purity metal salts are gained.
To propose the suitable recycling process, RWTH-IME manages recycling trials follow the concepts 3a and 3b. Four types of batteries NCA, NMC, NCA and LFP originating from the Helios consortium are treated. Each battery cell was treated in a resistant furnace at 500 °C, which is connected to the exhaust system of the IME and was flooded by a cover gas (Argon). The mass balance results shows that an average 22% of weight loses are evaluated because of the volatile organic compounds (VOC) originating from the electrolyte, separator and binder.
After pyrolysis the cells were manually dismantled (see figure 14). The cells were separated into the fractions Al casings including pins, Cu foil, Al foil and fine electrode material. In some cases the electrode material reacted during pyrolysis with the Al-Foil. Then the electrode material was difficult to separate from the Al foil because it was melted to the foil or the foil became so thin and brittle that it crumbled away in lots of small pieces just by touching it. In those cases the Al content went almost completely into the fine fraction.
Figure 14: Dismantling steps: Al-Foil, Cu-Foil, Separated electrode material
The pyrometallurgical treatment (3a) of the fine fraction is done in a submerged electric arc furnace. To find a good slag system, which have a low solubility for Li-oxide and still have a good performance with a Ni-Co-Mn-alloy, Li-solubility test and equilibrium tests have been conducted. The slag achieves good results at an electric arc furnace treatment step.
In the hydrometallurgical route (3b), a hydrometallurgical recycling process has been designed and investigated to recover valuable metals from fine fraction. The feasibility of recycling of pure graphite from fine fraction has been investigated. The best efficiency was achieved as Co: 99.9%, Cu: 99.9%, Li: 99.5%, Ni: 99.9%.(s. Figure 15)
Figure 15. Effect of acid kind and oxidizing agent on the leaching of Co, Cu, Li and Ni from electrodes of Li-ion batteries ([HCl]=4 mol/L, [H2SO4]=2mol/L, [H2O2]=50 g/L, T=80 ˚C, S/L=100 g/L, t=2h,rotation speed=300rmp).
A comparison between 3a and 3b has been implemented (Table 4). The different criteria have been selected. The hydrometallurgical process has higher selectivity and less Offgas and energy consumption than pyrometallurgy. However, it has also some disadvantages, such as low space-time yield, high water demand, high additive consumption.
Table 4 : Comparison of hydro and pyro process for EV batteries
(++ = positive impact; -- = negative impact.)
In summary, several possible recycling processes for electric vehicle batteries have been successfully developed. The feasibility of them was estimated by comparing their advantages and disadvantages in aspect of process selectivity, safety, efficiency and possible products. The most suitable recycling concepts 3a and 3b are experimentally validated. The important experimental methods and parameters have been investigated and discussed. Additionally a risk analysis was made for the concepts 3a and 3b. According to the risk analysis the pyrolysis of Li-Ion battery cells affords safety measures to reduce the probability or the severity of possible toxic gas emissions. The recycling efficiency (RE) calculation shows that all three recycling concepts, 1, 3a and 3b, meet the RE-target of 50% imposed by the EU-Directive 2006/66/EC.
To identify the extra needs when scaling up from single cells to modules and finally to the entire battery pack, all elements of (H)EV battery recycling processes must be considered in order to assure optimal balance between the relevant societal, economic and environmental sustainability pillars, therefore a fishbone diagram is designed and presented below (Figure 16).
Figure 16 : Fishbone Diagram Illustrating the Different Aspects of Battery Recycling
Possible motivations for a partial (or complete) disassembly are presented:
• Technical: It is a technical challenge to introduce battery packs up to 400 kg to the proposed recycling schemes (material handling and equipment sizing implications). However, future large scale facilities should be designed to handle at least up to 200kg battery packs.
• Environmental: The auxiliary elements include relatively pure fractions (steel, Al, Cu) that don’t need complex metallurgical processing. An up-front removal/separation of these parts creates some financial burden but, depending on the recycling process used, may deliver also some environmental credits (downstream processing simplified)
• Economic: Trade-off exists between the dismantling costs (operator time) and higher processing costs (equipment).
EV battery recycling is a combination of pre-treatment and metallurgical and chemical processes; the optimum combination depends on many variables (volume, battery chemistry and assembly design, investment and labour cost, ).
Conclusion and perspectives :
The project is showing significant information on the differences between the 4 cell technologies. This will provide considerable assistance to future R&D and industrial developments and give a good overview of the most used Li-ion technologies.
The main results, conclusions obtained within Helios project can be summarized in the table 7:
Table 7 : Overview and synthesis of Helios results
In conclusion, no technology presents the best features on performances, safety, economical and recycling points of view. Compromises must be done to do the best choice according the application and the technology selected.
However, we can emphasize that NMC based cells showed a slightly lower capacity than the NCA based cells, but continued material improvement and further adaptations in the cell geometry may lead to an equivalent energy density to the current NCA product. LMO/NCA-blend cells are definitely significantly lower in their capacity. Future activities with respect to an optimization in the mass mixture and the recipe may lead to at least partly compensate this disadvantage. Results with LFP based cells selected in Helios project were rather disappointing, particularly with regard to life endurance but it is expected that optimization with this chemistry and the improvement of the moisture content specification of raw material will overcome the life problem. Also the capacity of these cells may be further increased without sacrificing their advantageous abuse tolerance. This makes them interesting especially for those PHEVs with a relatively small battery system.
Potential Impact:
The reduction of emissions (CO2, particles …) in the atmosphere is THE challenge of the next decades. The development of electric and Hybrid vehicles will deeply contribute to this objective and to fulfil the CAFE target (Corporate Average Fuel Economy) which is 95 g CO2/Km end 2020.
High level of knowledge and good collaboration between the main actors (car and batteries manufacturers, energy holders but also R&D laboratories) are the key of the success of this development.
By achieving and evaluating new, safer, more efficient and cheaper Li-ion cells, HELIOS will contribute to an enhanced use of low or zero emission vehicles, which will provides citizens better health and better quality of life.
Impact on European Research :
The main objective of Helios project is to gather European car manufacturers, battery manufacturers, research organisations and recyclers with their interdisciplinary skills in order to form a strong collaboration, to generate new knowledge and recommendations that will be implemented in future products.
Six European OEMs, who are the main end-users, were deeply involved in the consortium. Furthermore, there were a very good complementarity and fruitful interaction between partners (industrials, universities, R&D labs and technical Centers).
Scientific and technological impacts and reinforcing European competitiveness :
The comparisons covered in Helios project will be a good support to the automotive industry, research organisations and legislative bodies in their decision making for the future development of electric and hybrid electric vehicles :
- For the end users, having tests procedures for safety and electrical tests, robust and agreed
- Ageing model will give a helpful tool to define the ageing mechanisms
- Selection and evaluation of the most- promising positive electrode materials on safety, performance and economical points of view.
Finally, we can conclude that each of the four Li-ion chemistries have some advantages / disadvantages / risks and opportunities. A compromise has to be done according the technology and the application chosen.
Main Dissemination activities :
The Dissemination activities were conducted throughout the project, from the first year and will go on during the next months to disseminate all the results.
Within the EUCAR organisation, yearly presentation were explained and discussed during the EUCAR program board meetings. A poster was also established and presented during the four last EUCAR conferences. Furthermore, the test procedures developed in the WP3 were introduced and promoted in the Working Group EUCAR dedicated to Battery eVs, and fuel cells eV.
Throughout all the duration of the project, there was a large involvement of the coordinator in seminars & workshop organized by the Green Car Initiative (July, Nov 2012 and April 2013). It was an opportunity to present and share Helios’s results and experience with industry, scientific community and the European commission. These meetings promote also widely the dissemination and the sharing between the European projects.
Several papers and talks were also presented in International conferences by Helios partners (batteries 2012, EVS 26 & 27, IWIS …)
The results of Helios will continue to be largely disseminated to a wide community via scientific presentations and dissemination via the public web site and via distribution of the twenty deliverables with Restricted dissemination to selected beneficiaries (scientific community, experts, other FP7 projects …).
-HELIOS provides tests procedures to carry out safety and electrical tests within the project but they can be widely used by similar testing activities. The deliverables are public reports, they are available on the Helios website and they were presented to EUCAR experts working group. The procedures have been also shared with other European projects (ELIBAMA, EUROLIION, AMELIE, EASYBAT …) :
- Cell specifications applicable to both electric and hybrid electric vehicles (see public Deliverable 3.1)
- Performance, cycle and ageing test procedures, with links to other existing procedures available world-wide and characterisation of the cells (see public Deliverable 3.2)
- Safety test procedures for performance under electrical/thermal/mechanical accident or abuse for new and aged cells (see public Deliverable 3.3)
- post-mortem analysis performed in the WP2 are confidential. But an abstract of the deliverable 2.5 resuming the interpretation of the ageing results measured on Helios cells (on electrodes, separators and electrolyte) will be uploaded on the Helios public website to benefit to the scientific community and R&D labs. Based on their experiences, some recommendations were also emphasized to select the right analysis methods and to prepare and handle the samples. In particular, for post-mortem analysis it is important to open the cell under protective atmosphere to avoid any contact with air and moisture and generate “parasite” reactions.
-Development of Procedures and recommendation for handling of used cells and recovery of materials during recycling process (see Deliverables 8.1 8.2 & 8.3) taken into account economical, Life Cycle Assessment and safety points of view were established. They describe and compare the main process and the best practises. These deliverables have been sent to RECHARGE and EBRA (European Battery Recycling Association) and to EUROLIION project.
-Economical assessment at material, cell and pack level will be also shared with other FP7 projects (AMELIE, EUROLIION…). A specific report, resuming the main results described in the deliverables 7.1 7.2 and 7.3 has been consolidated and will be sent to main suppliers and shared with other battery’s projects (EUROLIION, AMELIE, ELIBAMA …).
List of Websites:
website : http://www.helios-eu.org/
coordinator : RENAULT – Frédérique Del Corso – Frederique.delcorso@renault.com - 1 av du golf- API TCR LAB 0 12 - 78084 Guyancourt- France
WP leaders :
ADAM OPEL AG, Russelsheim – Germany,
CNRS-LRCS, 80039 Amiens – France
JCHaR, 30419 Hannover, Germany,
SAFT, 33074 Bordeaux – France,
EDF, 77818 Moret/ Loing – France,
INERIS, 60550 Verneuil / Halatte – France,
PSA , 78955 Carrières sous Poissy- France,
RWTH-IME, D 52056 Aachen - Germany
HELIOS consortium : 18 partners are involved from 6 european countries
