Community Research and Development Information Service - CORDIS

FP7

BATTERIES2020 Report Summary

Project ID: 608936
Funded under: FP7-NMP
Country: Spain

Final Report Summary - BATTERIES2020 (BATTERIES2020: TOWARDS REALISTIC EUROPEAN COMPETITIVE AUTOMOTIVE BATTERIES)

Executive Summary:
BATTERIES2020 (http://www.batteries2020.eu) is a three-year Large-scale integrating collaborative project, part of the European Commission’s Seventh Framework programme GC.NMP.2013-1, “Improved materials for innovative ageing resistant batteries”. BATTERIES2020 started in September 2013 and has ended in August 2016.
The project aims to improve performance, lifetime and total cost of ownership of batteries for Electric Vehicles (EVs) by the simultaneous development of high-performing and durable cells, reliable lifetime prediction, understanding ageing phenomena and assessment of second life in renewable energy applications. A lifetime of 4000 cycles at 80 % DOD and an energy density of 250 Wh/kg are the goals for the developed batteries.
To reach these goals, the Batteries2020 project has taken several steps with three parallel strategies: 1) highly focused materials development; 2) understanding ageing and degradation phenomena; and, 3) routes to reduce battery cost.
Several generations of improvements have been achieved for materials, cells and methodologies.
Batteries2020 is an initiative of a consortium of nine public and private partners from six different European countries with a total budget of 8.4 million euro. The BATTERIES2020 consortium is a unique constellation of European partners with the proven capabilities to drive pilot production into commercialization. The project combines a wide range of expertise, ranging from materials development and battery production to lifetime characterization, and viability and sustainability assessment of the chosen approach. This has allowed an effective and dynamic R&D process with multiple tasks running simultaneously.

Project Context and Objectives:
2. SUMMARY DESCRIPTION OF PROJECT CONTEXT AND OBJECTIVES
2.1 Impact level objectives
Europe has set ambitious climate change targets of decarbonising all road transport in the coming years. In many EU countries, EV adoption plans are designed to build upon existing green transport programmes, where environmental and financial benefits are offered to ultra-low carbon emission vehicles. The aim behind these plans is to help improving local air quality with a resultant improvement in public health and wellbeing and contribute toward further green energising economy. Nevertheless, the high cost of Li-ion batteries is a major barrier for the accelerated development and market penetration of EV. The high manufacturing costs of Li-Ion batteries are a big challenge, and it is accepted that cost per kilowatt hour of battery capacity needs to be drastically reduced in order to become competitive.
BATTERIES2020 chases Li-Ion batteries cost reductions via several strategies at different steps of battery value chain (manufacturing, use, reuse and recycling). Besides increasing its lifetime (by means a better understanding of ageing mechanism and better materials resistant to ageing), the project has pursued a battery size reduction by optimised control strategies through well defined State-of-Charge (SoC) algorithms enhancing battery durability, and specifications optimization by means of a reliable diagnosis of cells State-of-Health (SoH) modeling.
BATTERIES2020 project also has sought increasing the energy density of large format Li-Ion batteries with the formulation of new cost-effective materials.
Besides, the battery cost reduction is also analysed via recovering a fraction of the battery’s cost by its reuse in second life applications, increasing the battery residual value.
The path towards truly mass-scale production of large lithium-Ion batteries as necessary for electric vehicles is confronted with several serious challenges: cost, quality, environment, process scale-up, etc. Moreover, Europe faces strong competition from Asia and the USA where more investments and production capacities for Li-Ion batteries currently exist. BATTERIES2020 has targeted to help in the development of a competitive European industrial cell production. The demands placed on the production environment by industrial mass production of Li-Ion batteries are huge. The issues are not only cost reductions, but is also focus on maximum safety and stringent quality levels during production, which is one of the major pre-requisite for extending a battery´s service life.
2.2 BATTERIES2020 approach
BATTERIES2020 combines a wide range of expertise, ranging from materials development and battery manufacturing to lifetime characterization, viability and sustainability assessment of the chosen approach. Several generations of improvements have been envisaged for materials, cells and methodologies. This has allowed an effective and dynamic R&D process with multiple tasks running simultaneously.
The project plan was designed towards efficient achievement of significant results. A commercial 1st generation reference cell, manufactured by EIG, was analysed at the very beginning of the project to be the basis of a thorough ageing understanding, development of standard methodology, modelling and lifetime prediction validation. In parallel, materials were developed towards an intermediate 2nd generation of improved cells which was characterized through the optimized protocols and test procedures developed while analyzing 1st generation reference cells.
In parallel to 2nd generation ageing, the project assessed second life uses of 1st generation cells and further developed materials for the 3rd generation cells towards EV targets. The project was thought in terms of efficient iteration loops promoting rapid generation of results and know-how that could be implemented into the new generation of materials, cells, methodologies and test procedures.
2.3 Scientific & Technological objectives
The project aims to improve performance, lifetime and total cost of ownership of batteries used for EVs by the simultaneous development of high-performing and durable cells, reliable lifetime prediction, understanding ageing phenomena and assessment of second life in renewable energy applications.
According to the previous definition, some specific objectives have defined the project:
• A competitive European industrial cell production, through the development of new materials for battery components, development of recycling processes and review of environmental issues related to Li-Ion battery use.
• Standardised methodology for battery life testing, as a way to reduce costs.
• Thorough understanding of ageing and degradation through combination of tests, models.
• Development of models (electrical, electrochemical, thermal, lifetime).
• Methodology for lifetime prediction.
• Application areas for second life use.
• Effect of cell variability on second life use.
As a consequence of the previous steps of development, the main goal of the project is achieved:
• Battery Cost reduction: This pillar of the project is reached via a better ageing understanding and optimisation of battery size and use specifications, better materials resistant to ageing, higher residual value through second life application understanding and reliable diagnosis of cells State-of-Health (SoH).
The figure bellow summarises the project strategy:

Figure 1. BATTERIES2020 strategy towards goals
2.4 Project structure
The correlations between experimental activities and ageing phenomena involved in WP2 (Improved Materials), WP3 (Battery and testing), WP4 (First Life Ageing), WP5 (Modelling) and WP6 (Model validation) are depicted in Figure 2 (bellow). Starting with baseline 1st generation commercial cells, a fully characterisation within WP3 was done to determine the level of reproducibility of measurements amongst partners. Once the testing methodology and reliability of results was determined, these 1st generation cells were subject to a wide variety of ageing conditions related to several regimes of EV operation. These ageing conditions were agreed and work was organised amongst partners to simultaneously collect and analyse data in the most effective manner. Post-mortem analysis has been periodically performed at several stages of ageing for selected experiments. This procedure allowed the identification of specific mechanisms involved in the battery degradation, as well as to relate the level of degradation with respect to the operation conditions, determining thus the main ageing impact factors.
Specific experiments were performed within WP5 for the development of precise electrochemical, electrical, thermal and lifetime models which provided a thorough understanding of short and long term phenomena occurring within the cells. In particular, advanced techniques such as SEM-EDX, XPS, AES, STM and AFM, together with impedance analysis were used to determine variation in electrodes layer thickness, conductivity, variations of electrode/electrolyte interface, etc., all of them implemented in the electrochemical accurate model.
Accelerated (WP4) and real profile (WP6) ageing tests were performed. Accelerated testing together with post-mortem analysis was used for understanding ageing performance and identifying critical factors that cause significant degradation. Real-time data using EV driving profiles from field tests were performed to validate the developments, focused on predicting the lifetime of 1st generation cells and assessed the achievements compared to the proposed EV durability goals.
Outputs from this work were used as valuable information to refine the routes for the development of next 2nd and 3rd generations of cells. These data were crucial for the selection of best options. 2nd generation cells were benefited from these detailed performance evaluation; modelling and ageing methodology assisted the optimisation of experimental matrixes used with these new 2nd generation cells.
Lifetime prediction according to initial parameters of 2nd generation cells was attempted. The optimised ageing of 2nd generation cells (reduced experiments taking into account main impact factors) was performed and the modelling developed for 1st generation cells was applied. The accuracy of modelling with respect to experimental data and lifetime prediction was then quantified. 2nd generation cells allowed to progress towards the performance and life targets of the project and in parallel were used to validate the ageing and modelling tools developed for 1st generation cells. This was an attempt to provide a robust prognosis methodology for batteries EV performance evaluation.
The results of this second loop were then used as input for materials development and final selection of the 3rd generation of cells. In parallel, a strong effort in materials and battery development was pursued in WP2 towards meeting EV targets (250 Wh/kg, 4000 cycles at 80% DoD). This effort was enhanced by the inputs of ageing, modelling and validation methodology described above (WP3 to WP6).

Figure 2. Correlations of research activities of WP2, WP3, WP4, WP5 and WP6. Yellow boxes correspond to expected critical results output of the combined work from all work packages

Project Results:
WP2 - Improved Materials
The leader of this work package has been UMICORE. The specific objectives of the work package were the following:
To Improve existing electrodes materials and electrolyte compatibility, by means of:
• To define materials’ specifications in terms of performance, stability and cycling.
• To characterize optimized materials (composition, morphology, surface chemistry) in order to be able to understand links with ageing behaviour.
• To perform an electrochemical characterization of electrodes in half cells/laboratory cells for screening best choice of materials.
• To upscale and supply optimized materials (kg scale) to battery manufacturer to implement in 2nd and 3rd generations of ageing improved high energy cells.
• To make a preliminary economic assessment and life cycle analysis (LCA) of these optimized materials.

Active materials specifications: The analysis of 1st generation reference commercial cell specifications (NCM/graphite system), performance limitations and targets was done. Specifications and targets were defined for the improved active materials at this stage. Active materials according to this specifications review were developed (kg scale) in following tasks for supplying for electrode processing, cell development and production. The following targets were pursued: High performance cathode-electrolyte system improvement towards target of 250Wh/kg and higher stability and cycling: fine tuning of electrolyte/electrodes system composition towards 4000 cycles at 80% DOD. Special emphasis was put to the development map to achieve a successful industrialisation of materials and batteries to be successfully introduced into the market.
Development and characterisation of ageing-improved active materials. Based on the previous analysis, optimization of active materials in terms of ageing and performance was done. Post mortem analysis performed in WP4 and WP7 allowed defining the root causes for failure mechanisms. Specific materials analysis techniques (XRD, ICP analysis...etc) were used to translate failure cause into material improvement strategy. Various development paths were looked:
i) Composition optimisation, surface modification, blends of active materials... etc. ii) Development and preparation of formulation for the slurries (electrode pastes). iii) Coating of electrodes at laboratory scale and on pilot line. iv) Electrolyte optimisation according to cathode system selection). These materials were fully characterize in terms of physical and chemical properties as well as in terms of basic electrochemical testing (laboratory cells – coin cells and lab full cells). Electrolyte option suitable for the cathode chemistry was chosen and the admixture of additives and delivery of electrolyte decided.
Up-scaling of optimized materials for 2nd generation cells. Economic assessment. Once confirmation of the preferred optimised materials to be further used in the 2nd generation, upscale of the selected optimised materials was done. First products were supplied in WP3 for preliminary assessment and battery development. Then, samples at the 120 kg scale were needed for pilot line production of ageing improved 2nd generation. An economic assessment and LCA was done, and data were provided for Life Cycle Cost analysis to WP8.
Further materials improvements using ageing understanding. 3rd generation cells. The results of ageing analysis combined work of WP4, WP5 and WP6 was used to perform further materials optimisation, following the procedure defined previously, i. e. physical and chemical characterisation, laboratory scale and pilot scale materials production and characterisation. This third loop of optimisation enhanced the development of materials with further improvements in performance, stability and cycling towards EV targets. These new materials were also fully characterized in terms of physical and chemical properties as well as in terms of basic electrochemical testing (laboratory cells – coin cells and lab full cells).
Up-scaling of optimized materials for 3rd generation cells. Economic assessment. After confirmation of the preferred optimised materials to be further used in the 3rd generation of cells, the selected optimised materials were further up-scaled. Delivery of a first batch of material was done for battery development prior to battery pilot production. An economic assessment was done and partners were provided with all LCA related data for LCC in WP8.

Outcomes and outlook
The most relevant outcomes for the work package are:
• Two new chemistries for NMC cathodes.
• A significant €/kWh decrease of around 40% at the material level for 3rd generation cells.

WP3. Battery and testing
The leader of this work package has been LECLANCHE. The specific objectives of the work package were the following:
To produce the different generation of cells and establish testing protocols, by means of:
• To use reference cells for ageing experiments.
• To obtain ageing improved 2nd generation of cells.
• To obtain 3rd generation cells to further approach EV performance targets for ageing resistance and high energy batteries.
• To standardise testing protocols amongst partners.
• To perform a reliable initial characterisation of the 1st generation (reference) cells.
• To carry out statistical analysis (reproducibility and reliability) of cells performance.
• To perform a reliable characterisation of the of 2nd and 3rd generation cells.
• Recycling analysis of 1st and 2nd generation cells.

Obtaining the 1st generation reference cells. The project starts with commercial Li(NiCoMn)O2-based cathode reference cells , manufactured by EIG. These NMC cells offer a good compromise between safety, cost and performance for demanding applications such as automotive. Automotive cells using this type of chemistry are developing energy densities in the range of 160 to 180Wh/kg BoL (beginning of life) and are able, in EV type commercial cells, to perform over 3000 cycles at 80%DOD.
Standardization of cell characterization amongst partners. The establishment of the tests and procedures undertaken when testing partners receive cells from manufacturer, including preconditioning actions, control of cell temperature and specific types of cycling profiles was performed within this activity (the specific characterisation measurements and output parameters were brought together and statistically analysed in other task). Procedures for performance characterisation to evaluate parameter check-ups were also harmonised. The initial standardisation methodology and the level of noise and deviations encountered were used to define the testing methodology in WP4 and WP7. The number of experiments repetitions for this task was equal to the number of cells distributed among partners for the different WPs. The testing partners developed testing procedures and shared their experimental results to obtain a robust and uniform methodology that provided a reliable comparison tool for a wide number of experiments.
Statistical analysis. Determination of initial 1st generation cell baseline and its reproducibility and repeatability. Results from standardised cell tests and characterisation carried out in previous task were the input of a detailed statistical analysis, with the objective of determining the overall variability amongst cells performance and deviations from each testing Institute. The level of noise, standard deviations, reliability, reproducibility and repeatability was determined and the initial cell baseline performance was defined. This baseline was a critical input for WP4 to WP7 and the study was statistically completed by including initial characterisations of reference cells used in these WPs during first loop.
Obtaining ageing improved 2nd generation of cells on pilot line. The results from first loop of ageing modelling and validation (WP4-WP7) together with parallel materials optimisation (WP2) obtained during the first loop of the project was used to produce a 2nd generation of ageing improved cells. Leclanché was responsible of the pilot line production of sufficient cells for the second loop assessment of first life ageing. The new cathode material required the development of an adapted slurry formulation for the electrode paste. Binder and conductive additives needed to be selected and a recipe in lab scale trials developed. An initial batch of at least 3 kg was necessary. For cell production on the pilot line the slurry preparation mode was adapted and some amount of cathode material was necessary for pilot trials in advance of the cell production.
First selection of appropriate electrolytes was done with laboratory scale cells; however, the first full cells from the pilot line were needed to test and verify. After selection of the right electrolyte, the overall cell chemistry could be defined, an electrolyte manufacturer commissioned with electrolyte preparation and full cells produced in the requested number of cells. A reduced number of cells were produced than for first loop because part of the objectives was the optimisation of testing procedures and less number of experiments.. The cell characterisation and statistical analysis was repeated and optimised experiments in WP4, WP6 and WP7 were then performed.

Characterization of 2nd generation cells. The methodology and protocols established previously was used to characterise improved cells. The statistical analysis was also performed to assess the reliability and variability of this 2nd generation of cells and to establish the initial baseline for second loop of WP4 to WP6.

Obtaining ageing improved 3rd generation of cells on pilot line. Further results and conclusions from progress in ageing, modelling and validation (WP4-WP7) together with parallel materials optimisation (WP2) was used to produce a 3rd generation of ageing improved cells with high energy density and optimised stability. A reduced number of cells were produced for proof of concept and performance targets. The cell characterisation and statistical analysis was repeated and preliminary stability testing was attempted. No in-depth ageing assessment was pursued due to timeframe of the project; however, a minimum number of ageing experiments were performed for preliminary assessment.

Characterisation of 3rd generation improved cells and statistical analysis. The methodology and protocols established previously was used to characterise 3rd generation improved cells. The statistical analysis was also performed to assess the reliability and variability of this generation.

Implementation of monitoring control, thermal management and other system improvements. Adjustments in monitoring control, thermal managements that had significant impact in improving ageing of lifetime assessment were implemented in the 2nd generation of cells for validation and verification of significance.

Recycling analysis of 1st and 2nd generation cells. A recycling assessment of cells was performed to be combined with inputs from materials developers and battery manufacturer. The work was divided as follows:
• Design of a potential recycling process: to screening for a potential recycling processes and provide a forecast of the possible output product compositions. All potential (feasible) recycling processes generating concerned chemical compounds will be then evaluated, highlighting the necessary development / optimization to achieve the targeted specified products.
• Experimental recycling tests (process development): Based on the available battery cells in tests, the ability to recycle the battery system was checked and compared with other battery systems.
• Consideration of full battery packs recycling. The scaling up aspects from single cells to modules and especially large battery packs demanded additional treatments regarding full battery pack recycling. A basic environmental comparison of the identified recycling processes was carried out. Based on the results gathered additional R&D for battery pack recycling was identified.
The recycling process required approximately 10 Kg input material (battery cells) for each experimental batch. To verify recycling results, approximately 10 experiments per battery system were needed. The results of this task was used later in WP8 for assessing sustainability and environmental issues.

Outcomes and outlook
The most relevant outcomes for the work package are:
• Improving cell density to 250 Wh/kg
­ More development at the material level is necessary (before assembling).
­ Stability of new cathode material
­ Electrolyte/Material interactions

WP4. First Life AgeingThe leader of this work package has been RWTH-ISEA. The specific objectives of the work package were the following:
To perform and complete the First Life Ageing for all generation cells, by means of:
• Joint analysis of a wide range of ageing conditions under diverse EV user profiles.
• Identify and explain degradation mechanisms through electrochemical tests, electrical post-mortem and statistical analysis.
• Quantify lifetime improvements in 2nd and 3rd generation cells compared to reference cell.
• Develop standardized test procedures related to cell ageing under EV conditions.
• Quantification of State of Health (SOH)

Determination of ageing protocols. The definition of a clear and extended procedure to perform the accelerated ageing tests was carried out and the determination of the ageing matrix was performed: the stress factors (e.g. T, DOD, SOC, abusive conditions, etc) and their respective relevant number of levels, the definition of state of health characterisation tests, the parameters measured (capacity, internal resistance, among others), the precise conditions at which will be tested (temperature, current, frequency, etc) and the intervals of the check-up and the duration of the tests. The ageing tests and variables to be analysed were distributed amongst partners for the most efficient and complementary use of resources. The baseline of 1st generation cell was used to confirm the validity, level of noise and comparability of results obtained at different institutes and the reliability of the results related to varying ageing conditions.

Ageing of reference 1st generation cells. A complete degradation and failure analysis of the 1st generation cell was performed. Characterisation tests (EIS, electrical and thermal) defined in WP4 was performed periodically in order to assess cell’s state of health. The cells were thought to be under testing up to the EOL defined for electric vehicles. This investigation attempted to cover most ageing conditions expected in EV applications:
• Accelerated calendar ageing.
• Accelerated cycle ageing.
• Extreme conditions and safety.
• Types of charging: Special attention was paid to fast charging/discharging as the most challenging mode, in order to prove its feasibility and provide possible solutions in terms of cooling strategies to preserve safety. Apart from the accelerated ageing tests, also tests under real conditions were performed in WP6 to analyse the possibility to extrapolate the accelerated tests to these conditions.
The test procedures developed within this work were compiled in WP6.

Post-Mortem analysis Selected cells were taken from the 1st generation ageing tests at different times to evaluate the ageing effects. The results from the post-mortem analysis were compared with the non-invasive electrochemical characterisation performed during the ageing tests to find a relationship between the ageing mechanism observed in the post-mortem analysis and the stress factor used in the test condition. The influence of the different conditions on the ageing effects were analysed to understand the ageing processes and to give input to the ageing model and the electrochemical model (WP5). Special attention was taken to the methodology for opening and disassembling the cells safely without significant additional degradation of the components.
The selected cells were opened under argon atmosphere and the extracted materials analysed using different electrochemical, analytical techniques, mass and porosity measurements, as well as ICP measurements. Dedicated methodologies were proposed for determination of the ageing processes and parameters that further were used in the electrochemical model.

Understanding of ageing and degradation mechanisms The results from the ageing experiments and post-mortem analysis for 1st and 2nd generation were thoroughly analysed and used to update the state of the art in this field. An in-depth understanding of ageing and degradation mechanisms was carried out here and further supported with results from WP5 and WP6. The conclusions fed WP6 to improve the accuracy of the lifetime prediction model.
The partners involved combined their results and analysis to obtain a statistical and clear view of ageing and degradation phenomena inside the cell. A quantification of lifetime improvements in 2nd and 3rd generation of cells compared to reference 1st generation was attempted. UMICORE participated and translated the obtained results to materials level for improved materials development within WP2.

Statistical analysis. To overcome the imbalance in the electrical cell properties problem, it was necessary to quantify the variability of the electrical parameters within a batch of cells. The goal of this task was to analyse the variability of the intrinsic electrical properties of the cells while ageing. Due to cell ageing, the variability distribution tends to broaden, and the analysis becomes more complex.
For this purpose, each test was performed at least with 3 cells. Besides, some tests were selected to increase the number of cells (up to 10) to obtain reliable results in terms of statistics and significance of variability.

Ageing of improved 2nd generation cells. 2nd generation cells were aged in order to assess the improvements in first life ageing compared to 1st generation cells behaviour. The evaluation followed the procedures defined in WP4. However, only optimised experimental matrixes with reduced conditions were tested :
• Ageing tests: A reduced test matrix was defined. These tests were performed using the same methodology developed in WP4.
• Post-mortem analysis: The procedure is the same as in WP4. 1st generation and improved 2nd generation cells were compared to understand and quantify the improvements related to ageing resistance.
• Statistical analysis: statistical analysis was performed to evaluate the variability in the electrical properties of the improved cells during ageing, as described in WP4.

Ageing of improved 3rd generation cells. Significant parameters and critical ageing experiments were carried out at the end of the project to provide an initial evaluation of ageing performance of 3rd generation cells. The detailed work of analysing ageing of 1st and 2nd generation cells was used to extract meaningful experiments to provide critical information in a short period of time for the new cells. The testing of the 3rd cell started at the end of the project so that an ageing prediction was not possible, but even the first ageing points could give a hint of the later ageing behaviour.

Outcomes and outlook
The most relevant outcomes for the work package are:
Wide knowledge acquired about ageing tests, characterisation methodology and protocols.
• Ageing behaviour in lithium ion batteries -> Publications are in preparations
• Direct input from this project (testing routines for ageing) in new Horizon2020 Project: “Everlasting - Electric Vehicle Enhanced Range, Lifetime and Safety Through INGenious battery management”.
• Further projects between the material/cell developer and the research centres/ universities are likely.

WP5. Modelling
The leader of this work package has been VUB. The specific objectives of the work package were the following:
To develop and validate the modelling of the cells, by means of:
• Electrical, thermal and electrochemical characterisation of the battery cells specific to modelling.
• Development of electrochemical, thermal, electrical and lifetime models.
• Validation of the battery models.

Electrical, thermal and electrochemical characterization of the battery cells. The development of precise electrical, electrochemical, thermal and lifetime models based on a thorough understanding of the short and long term behaviour of the developed cells was carried out. Overall validation of the lifetime model with real life data was done in WP6. Modelling was applied to 1st and 2nd generation cells.
Some aspects of the characterisation were carried out in WP3 and WP4 (lifetime tests). The generation and collection of solid and reliable cell characterisation data were used as a basis for the development of accurate battery models. The general procedures were contrasted and combined with those from WP3 and compiled as “standardised data collection procedures related to modelling”.
Electrical characterisation: Innovative electrical test methods to tackle battery performance, electrical behaviour and variation between the cells have been used. A set of dedicated electrical characterisation tests, performed at a wide range of different operating temperatures was used to generate an accurate electrical characterisation data for modelling. Lastly, these tests have been repeated also on partially aged cells from WP4.
Thermal characterisation: Several tests required for the estimation of the main thermal battery model parameters (the heat capacity, the internal resistance and the entropic heat coefficient) were done. The internal resistance was determined as a function of both temperature and SoC by applying constant current discharge pulses. Open circuit potential experiments were performed to determine the entropic heat coefficient as a function of SoC.
Electrochemical characterisation: All measured and collected data in combination with the knowledge of the structure and composition of the cell were analysed. The electrochemical analysis included: dimensions of the layers, variation of layer thickness within one cell, conductivity of the layers, conductivity of the electrolyte, identification of electrode compounds, conductivity of the separator and collectors. Some input came from specifications provided by Leclanché (WP3); others were obtained by performing dedicated electrochemical characterisation techniques GITT, EIS, entropy test, OCP measurement, XRD. Post-mortem data from WP4, as well as dedicated electrochemical characterisation tests performed in WP5 provided the information concerning the beginning of the first life of the cells. With respect to the ageing, dedicated electrochemical test procedure has been elaborated and is being carried out. These different parameters and electrochemical characterisation test results were used as inputs for the electrochemical models.

Development of electrochemical model. The development of an electrochemical model using data from previous task, WP3, WP4 and WP7 data was carried out in this activity. The model allowed evaluating voltage response under different load conditions (constant and dynamic) and can be used to provide the cell designer with a clear insight in the main electrochemical parameters, which change during operation and ageing. The electrochemical model can be used as a useful tool to understand the cell operating mechanisms. A dedicated sensitivity analysis has been developed and applied for the NMC chemistry. Dedicated electrochemical characterisation tests have been used to determine the main parameters for feeding the electrochemical model. Dedicated electrochemical relationships were used for evaluation of the voltage response in the cell and charge transfer processes occurring across the electrode-electrolyte interfaces

Development of thermal model. The work carried out here focused in the study of the influence of temperature on battery behaviour, to perform an entire model that simulates a 3D environment. This model has made possible to describe the battery behaviour by using and advanced Computational Fluid Dynamics simulation tool, which allowed exploring the battery weakness in terms of heat development, that can be mapped out and thermal manage in a battery pack.

Development of electrical model. The development of a dynamic electrical cell model able to predict accurately the electrical cell behaviour under different environmental conditions was done here, with a good response during transient as well as steady state periods. The model parameters were estimated based on the advanced estimation and minimisation techniques. This estimation technique is very fast, accurate and can be used for any cell model. The electrical model was developed in the Matlab/Simulink simulation environment due to its high integration properties into all electrical and electronic systems
Determination of SoC and SoH. This task focused in the development of control algorithms for an accurate estimation of the state of charge (SoC) and state of health (SoH), based on Extended Kalman Filtering methodologies.

Development of lifetime model The collected data from the discharge capacity, test and extended HPPC test (WP3 and WP4) were statistically analysed. The proposed tests performed on a fixed regular basis (e.g. every 100 cycles) were carried out during the first life of 1st and 2nd generation cells at the appropriate working conditions such as operating temperature, charge/discharge current rates, SoC-levels depth of discharge, storage temperature and calendar life. The collected data from the test-matrix allowed obtaining the mathematical lifetime evolution as function of the proposed working conditions. These mathematical relations have been used to build the lifetime model.

Validation of the battery models. The validation of the developed cell models from previous tasks was performed. Dedicated validation test procedures (dynamic and WLTC driving cycle based) were used, which provided measurement data for model validation.

Optimized modelling of 2nd generation cells. From the modelling tools developed in previous tasks, a review of methodology and results applied to 1st generation cells was performed. Extraction of key parameters, relevance of results, and quantification of success in validation and reliability of models was analysed to develop optimised characterisation and modelling tools to be applied in 2nd generation cells.

Outcomes and outlook
The most relevant outcomes for the work package are:
• Very good and validated dynamic electrical model for 1st and 2nd generation cells.
• Established electrochemical characterisation procedure.
• Good performing and validated electrochemical model.
• Good performing and validated thermal model + test setup.
• Good performing Lifetime modelling procedure and tool.
­ Advanced modelling procedures and tools for future research and consultancy.
­ Modelling & characterisation procedures will be used in other projects and future research.
­ Use of advanced models for SoC and SOH algorithms.
­ Development of electro-thermal model.
­ Evaluation of G1 cells’ thermal parameters (EHC) evolution during calendar and cycle ageing.
­ Optimized thermal management strategies can be developed.
­ Routes for further lifetime model improvements have been identified.
• Outcome of this project, useful for other projects: BATTLE project (national), FiveVB (EU), Orca, + other new project proposals.

WP6. Model validation
The leader of this work package has been IK4-IKERLAN. The specific objective of the work package is the following:
To perform the model validation in real conditions, by means of:
• To perform real EV profile experiments using thorough analysis of EV driving profiles from field test data.
• To develop a reliable lifetime prediction methodology based on validation with real EV profiles experiments and input from the understanding of ageing and degradation mechanisms.
• To validate the results of accelerated testing compared to real tests.
• To quantify lifetime improvements of 2nd generation cells compared to 1st generation reference cells.
• To obtain and validate standard test and characterisation procedures applicable at a European level.

Analysis of the ageing model under realistic EV working conditions:
Determination of representative EV working profiles based on real life data. A thorough investigation of different EV driving profiles was done and frequencies of important parameters were analyzed: distance travelled per day, travel time per day, average speed while driving and maximum acceleration. Additionally, charging strategies and seasonal temperatures that affect the degradation of the battery were also considered. All these parameters were combined to obtain the most representative EV working profiles used for real time testing.
Real test of reference cells using representative EV working profiles. Real tests were performed using the most representative EV working profiles defined previously. Characterisation tests (EIS, electrical and thermal) defined in WP4 were done to determine the SOH during the lifetime of the cell, up to the EOL. Some cells were tested under each profile, accounting around 24 cells. The experimental were complemented with thermal and electrical parameters related to real usage of EV (FIAT500e) during normal use. A data base of driving cycles was done. Statistical analysis was performed on following parameters: DOD, RMS current value, frequency range, etc. A load profile close to the real application profile was derived and compared to the current WLTC.
Validation of the accuracy of the lifetime model versus real testing. The lifetime model developed in WP5 was used to simulate the degradation of the cells under the driving profiles defined previously. A comparison of the simulated degradation with the real data obtained by experimental was analysed. This information was a feedback to WP5 for improvements of the lifetime model. The degradation of performance during normal use under different temperature conditions and driver behaviour was conducted in real conditions to evaluate and provide feedback on the lifetime model prediction.

Use post-mortem analysis to confirm the validity of the ageing model. Post-mortem analysis was done on real profile tested cells to extract important information: solid electrolyte thickness, decrepitating of the electrodes, change in the electrode materials or isolation of active material. This information assessed the assumptions for the electrochemical model. Some cells were stopped at midterm of experiments and analysed using post-mortem for enhanced understanding of degradation.

Understanding ageing and degradation mechanisms The conclusions from WP4 were taken at this point of the development, reviewed and analysed against the results from WP6. Once the life prediction tool was validated, the results from ageing experiment, post-mortem analysis and models was thoroughly analysed and used to update SoA in this field. Critical experiments and information was prioritised in order to produce and optimised ageing assessment methodology. The comparison of results from accelerated and real testing was thoroughly analysed.

Definition of the control strategies based on the models developed in WP5 and WP6. Establishing battery performance in comparison to the targets for electric vehicles (3000-5000 cycles at 80% DOD and 10-15 years of use) was the main objective under this activity. The models developed combining the work of WP4, WP5 and WP6 was linked to reproduce the electrical and thermal behaviour under different working conditions and during the cell lifetime. The model was used both to determine controls strategies that will assure the EV durability goals and to reduce cost by optimising sizing of battery pack.

Validation of lifetime prediction methodology using 2nd generation cells. A second loop was performed using improved 2nd generation cells developed in WP2 and WP3 to:
• Determine a reduced ageing matrix to completely characterise (in terms of the durability) the improved cells, checking the viability and implications in terms of time and cost (WP4).
• Use of previous models with current data and check their validity and the deviation. Determine the minimum experiments to make models suited to new batteries (WP5).
• Performing EV real profile experiments and validating the re-parameterised lifetime model.
• Revision of lifetime prediction methodology and check its applicability to other technologies and scenarios. The procedures from two first activities were applied here to validate the lifetime model (WP4, WP5) for the improved cells.

Development of standard test procedures applicable at a European level. Test protocols were defined accounting pre-conditioning recommendations and cells specifications (minimum representative size, materials for connections, ambient conditions, etc., with the objective to obtain a testing procedure applicable at a European level.
Basic tests guidelines were set for the following types of tests:
• Initial characterisation test procedures (thermal, electrical, electrochemical)
• Accelerated ageing test procedures (calendar and cycle)
• Ageing testing modes: climate, extreme conditions, types of charging, safety issues and abusive tests, cycle modes.
• Real testing using EV working profiles
• Standardised data collection procedures related to modelling
• Critical tests for lifetime prediction
• Recommendations for testing second life and definition of battery state of health

Three thematic workshops were organised (month 6, 24, 36) on the testing procedure.
Outcomes and outlook
The most relevant outcomes for the work package are:
• Real EV usage patterns studied. The validation profiles employed are in good agreement with the assessed usage real patterns (F500e roller bench).
• Implementation of an iterative validation approach, which allows further assessing the source of errors of lifetime predictive models.
• Battery ageing analysis under EV application: experimental results from realistic EV application profiles showed that calendar ageing is the main cause of battery ageing.
• For most EVs (not heavy duty vehicles), studying the calendar life of the batteries might be enough to evaluate battery ageing performance.
• Accelerated battery testing (WP4) proved to provide battery ageing representative results when compared to the dynamic validation more realistic results (WP6) à the accelerated testing approach was validated for ageing modelling purposes.
• Validation of the suitability of 2nd generation cells for EV application. Ageing performance of 2nd generation improved compared to 1st generation cells.
• Standardisation: need to contribute to Second Life battery testing was identified when evaluating the knowledge generated within the project (WP3 and WP7 testing procedures) and reviewing the available battery testing standards.

WP7. Second life Ageing
The leader of this work package has been AR. The specific objective of the work package is the following:
To perform the Second Life Ageing, by means of:
• To investigate second life ageing of 1st generation cells under second life applications in order to understand the ageing mechanisms beyond EOL defined for EV
• Assessment of suitable second life applications
• Analysis of interaction of heterogeneous cells, grouped into small stacks, in the second life ageing mechanisms.

Definition of the cycling program according the second-life application. Cycling conditions for the second life application for reference cells were determined and several second life applications considered determining specifications for second life use. For selected second life applications, the optimal size for ESS was calculated. The most suitable operation point and the charge/discharge cycles were defined for the applications. The charge/discharge profile was transformed into equivalent cycling series, with specific DOD and frequency.

Second life ageing of 1st generation reference cells according to second life cycling profiles. First-life aged reference cells were aged again following guidelines from previous task, (calendar and cycle ageing) using the most significant applications profiles defined previously. Regular “check-ups” were carried out following standard procedures from WP4. First life aged cells were used at the same second-life conditions. The history of battery during first life was taken into account for statistical analysis and for defining an appropriate SoH prediction technique.

Ageing of heterogeneous cell-stacks according to second-life cycling. Small stacks combining heterogeneous cells were tested, according to specific cycling patterns defined in the first task, to study the interactions’ between cells with different electrical parameters resulting from different first life ageing cycles. These ageing tests were conducted over small homogeneous and heterogeneous stacks under the same operating conditions in order to isolate the effect of the interaction amongst cells with different parameters.

Post-mortem analysis The influence of ageing conditions was analysed to understand the ageing processes and provide input to the lifetime model. The procedure was the same as the post-mortem analysis procedure of first life ageing.

Test of heterogeneous cells stack during their second life application A stack with aged cells with heterogeneous electrical parameters was done. The resulting battery stack, together with the previously designed BMS was tested in the lab under operating conditions that actually emulate its operating conditions in second-life applications. The cell module will be driven by emulator of PV panels, under controlled temperature. This experimental setup allowed reproducing realistic operating conditions during the second-life of the module, and was monitored during programmed second life tests. The cell parameters were measured and analysed in order to validate the effectiveness of the ageing models proposed in previous tasks.

Outcomes and outlook
The most relevant outcomes for the work package are:
• Two main applications for second life batteries were thoroughly analysed. à 2 congress presentations and a journal publication.
• A novel Second Life testing methodology was developed.à Being shared with other EU institutions (JRC) and projects (SASLAB)
• Second life batteries coming from different first life history were analysed. à Cells experiencing a change in the dominant ageing mechanism showed difficulties to be reused in second life.
• Second life batteries coming from different first life history were analysed. à The 80% SOH criterion for EV battery retirement needs to be reviewed.
• The DC internal resistance was proven to be an important ageing factor and a reliable source to select suitable second life batteries à It should be included in the EOL criteria and considered in the second life battery selection à The 16cells with similar resistance have been selected for the heterogeneous stack among the 20 available cells.
• Difficulties to operate with heterogeneous stacks/modules. à Modifications in the First life BMS might be necessary to adapt it for the control of second life batteries.
• Second life heterogeneous stacks are suitable for being implemented in industrial PV plants à they offer a suitable dynamic performance, while providing a sufficient state of health for REN application.
• Depending on the heterogeneity level, it might be necessary to implement an advanced BMS with individual cell balancing à continuous cell overvoltage hitting could be avoided.

WP8. Economic Assessment
The leader of this work package has been AR. The specific objectives of the work package were the following:
To analyse the economic viability of developed cells, by means of:
• Cost model and life cycle analysis.
• Business models.
• Safety and environmental impact.
Cost model assessment and life cycle analysis. The LCC cost model for the battery with improved materials was calculated taking into account the cost for all major components, with inputs from the previous packages. Ageing mechanisms identified were considered and the residual value calculated from the obtained data.
Second life applications and the final disposal of the batteries were analized. The cost calculation model allows sensitivity analysis: materials, temperature of operation, type of charge, etc.

Business model analysis under several considerations: cost competitiveness, sustainability and profitability. Two approaches:
• Business model of batteries developed within the project in EV application.
• Business model of EV batteries including a second life use: analysis of the technical feasibility and economic viability of reusing EV batteries for second life applications. A range of feasible options for second life applications will be identified. The development of different business models for the most promising option was done.

Safety and environmental impact of improved materials and battery technology. Two approaches were done:
• LCA: definition and assessment of the potential environmental impacts caused by EV battery systems and the benefits of second life applications for reducing these impacts.
• Safety analysis considering different risks for EV batteries

Outcomes and outlook
The most relevant outcomes for the work package are:
• Life Cycle Cost Assessment (LCCA) tool to calculate batteries LCC and analyze the suitability of the different second life stationary applications from a techno-economical perspective.
• Methodology to select the most suitable applications for the second life of EV batteries.
• Integration of several factors in the EV batteries Business Models based on “Business Model Canvas”.
• Life Cycle Inventory on NMC cells will provide a new benchmark for LCA and LCC studies.
• The methodology for LCI and LCA on NMC batteries would fill the current gap in research\literature.
• Safety analysis provides guidance to design and manufacturing of inherently safer battery packs.
• Environmental impact assessment of second use batteries

Potential Impact:
4.2 Wider socio-economic impact
4.2.1 Improvement of European battery production capacities
It is expected that NMC will be one of the dominant Li-ion cathode chemistries for automotive applications in the short term. The project results offer a unique opportunity for the European industry to be well positioned in this market. Leclanché's strategy is to expand its position as one of the leading lithium-ion cell producers and solution providers. BATTERIES2020 has provided a nice opportunity for LECLANCHÉ to take advantage of new market opportunities.
UMICORE is currently a leading supplier of Li-ion active materials for different applications, including automotive uses (third worldwide main cathode provider). By participating in this project UMICORE is able to offer new generations of materials increasing its portfolio of products. This will allow the company to be well positioned in the EV market, which is expected to grow significantly by 2020.
KELLEN EUROPE has increased the impact of the project outcomes in the European battery industry. This has been especially important for the development of the standardized testing procedure applicable at a European level.
4.2.2 Contribution to other project & further use in future research
The outcomes and the acquired knowledge of the project will be applied to a bunch of different projects, both at European and national levels. This includes optimised cost-effective testing procedures for battery advanced characterisation, ageing testing and battery modelling will contribute to
• European (H2020) program: Everlasting, FiveVB, ORCA
• National: BATTLE (IWT-SBO) project
Methodology and findings are being shared with other EU institutions (JRC) and projects (SASLAB, EC).
The application of these developments to other battery technologies different from Li-Ion needs to be checked.
4.2.3 Job creation and new products and services
Neither new job has been created as consequence of the project concerning to the three manufacturing companies in the consortium, nor spin-offs. Nevertheless, up to 6 theses will be completed based on project developments: four theses at VUB, one thesis at IKERLAN and one thesis at RWTH-ISEA. This will allow the access to a high quality jobs at European level.
As explained in exploitable of results chapter, a new cathode material with further improved electrochemical performance and cycle life has been developed in the project, under the patent application reference WO2016116862, and title: “Li NMC oxide cathode powders for high voltage Li-ion batteries”, by UMICORE.
Besides, electrochemical, thermal, electrical and lifetime models will be commercialized as services to the battery industry.
Economic assessment tools for battery sizing depending on stationary application have been developed and will be internally exploited.
As for standardization of test procedures, some gaps in the current European and worldwide status quo have been identified and highlighted. For second life batteries, the test procedures will be shared with the EC (JRC) in project collaboration (SASLAB).

4.2.4 Increased European research excellence
Another impact from implementing the work program is that the Consortium members become aware of the respective complementary competencies and thus can jointly tackle follow-up problems in the future. In addition, the project keeps up the knowledge and the expertise achieved in the past in an international environment of cooperation, helping European researchers to work together. This could also be useful for other countries with emerging interest on batteries development.
4.2.5 Safety
While the rate of failures associated with the Li-Ion use in EV is small, several well-publicized incidents related to these types of batteries in actual use have raised concerns about their overall safety. Test standards are in place that mandate a number of individual tests designed to assess specific safety risks associated with the use of lithium-ion batteries. BATTERIES2020 projects has contributed to enhance safety use by performing a safety analysis that provides guidance to design and manufacturing of inherently safer battery packs. While some standards development organizations are continuing to revise and update existing lithium battery standards to reflect new knowledge regarding lithium-ion battery failures in the field, BATTERIES2020 has identify gaps in existing procedure, and has elevated safety standards for lithium-ion batteries.
4.2.6 Environment
Increasing the numbers of electric vehicles can significantly reduce direct emissions of CO and air pollutants from road transport. However, these positive effects are partially offset by additional emissions caused by the additional electricity required and continued fossil fuel use in the power sector projection in 2050.
In the framework of 2020 strategy, the EU has committed to a 20% cut in its greenhouse gas emissions by 2020 compared to 1990 levels. The EU has also adopted a 2020 target improving energy efficiency in the union by 20%%, reducing 20% greenhouse emission and 20% of energy production from renewable.
The BATTERIES2020 project supports the achievements of those targets strongly and in various ways, enhancing the adoption of EV with cheapest and more efficient batteries, and enabling the RES connection to the grid with the use of second life batteries form EV.
The project thoroughly assesses and targets recyclability (WP3) and second life applications of the novel batteries, in addition its research on cathode materials will yield cells with higher energy density, leading to lighter batteries. The beneficial effects are multiple, not only are a more efficient use of natural resources and materials achieved, but the projects results can lead to lighter electric vehicles, what reduces vehicle energy consumption. Moreover the development of batteries with an improved second life facilitates the further deployment of renewable energy sources.
The assessment of sustainability, safety and environmental impact, as well as economic aspects is carried out in WP9.
4.2.7 Improved quality of life in urban environments
Air pollution seriously affects human health, damages our ecosystems and causes deterioration of buildings and monuments. Cleaning up our cities’ air is another key priority for the EU. The EU’s Clean Air for Europe strategy, which includes the Cleaner Air for Europe (CAFÉ) Directive (2008/50/EC), forms the overarching policy framework for achieving safe air quality levels for all citizens, notably those living in cities. Motor vehicles are another major source of air pollution in our urban environment. The EU regulates vehicle emissions through two Directives covering cars and vans (70/220/EEC) and heavy-duty vehicles (88/77/EEC), and a series of amendments which steadily tighten these emission standards. The Directive also addresses climate change by requiring a minimum 6% reduction of greenhouse gas emissions from road transport by 2020.
BATTERIES2020 aims to facilitate the massive adoption of EV in Europe by overcoming the main issues related to Li-Ion batteries: cost, safety and recycling.
4.2.8 Green mobility in urban environments
The environmental and safety benefits of new technologies will increase as new vehicles progressively replace old ones on the streets. Alternative fuels represent one of the essential parts in the sustainable mobility puzzle. Automakers support a widely available, diverse range of low carbon and renewable energy sources and technologies that includes electricity. Electrification of the mobility and transport system is an essential part of the alternative fuel mobility mix. Technology enables considerably lower CO2 and other greenhouse gases emissions, as well as lower polluting emissions, thus improving air quality. Road infrastructure is adapted to the use of vehicles carrying the latest technologies within the urban environment. BATTERIES2020 approaches aims to boost the electric car as the most promising alternative to urban mobility by providing long range high power longer life batteries for EV purposes.

List of Websites:
www.batteries2020.eu

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