Periodic Reporting for period 1 - HighSpin (High-Voltage Spinel LNMO Silicon-Graphite Cells and Modules for Automotive and Aeronautic Transport Applications)
Reporting period: 2022-09-01 to 2024-02-29
The objective of HighSpin is to develop high-performing, safe and sustainable generation 3b high-voltage LIB materials, cells and modules with a short industrialisation pathway and to demonstrate their application for automotive and aeronautics at TRL6.
The ambition of HighSpin is to lay the groundwork for the commercialization of Cobalt-free, LNMO||Si/Cbattery cells and the uptake of this (and other) battery technologies in automotive and aeronautic applications. Directly connected with this, HighSpin aims to further develop the competencies of the European battery industry with a focus on generation 3b battery cell chemistry and technology. This ambition is pursued through the following high-level objectives:
• Further develop the LNMO||Si/C cell chemistry, extracting its maximum performance.
• Develop and manufacture LNMO||Si/C cells fit for automotive and aeronautic applications.
• Design and demonstrate battery modules for automotive and aeronautic applications at TRL 6.
• Thoroughly assess the LMNO/Si/C HighSpin technology.
The ambition of HighSpin is to lay the groundwork for the commercialization of Cobalt-free, LNMO||Si/Cbattery cells and the uptake of this (and other) battery technologies in automotive and aeronautic applications. Directly connected with this, HighSpin aims to further develop the competencies of the European battery industry with a focus on generation 3b battery cell chemistry and technology. This ambition is pursued through the following high-level objectives:
• Further develop the LNMO||Si/C cell chemistry, extracting its maximum performance.
• Develop and manufacture LNMO||Si/C cells fit for automotive and aeronautic applications.
• Design and demonstrate battery modules for automotive and aeronautic applications at TRL 6.
• Thoroughly assess the LMNO/Si/C HighSpin technology.
In period 1, HighSpin updated the requirements for automotive applications, using as a starting point those of its predecessor project 3beLiEVe. Requirements for aeronautic applications were defined, and both sets of requirements (automotive and aeronautic) were superimposed to find common points and synergies that could be used for the development of testing protocols on cell and module level, which have also been developed. Additionally, an eco-design workshop on sustainable design choices for cells and modules was held, which generated ideas and recommendations.
On the materials development level, various LNMO and silicon graphite candidates have been screened, and electrolyte development has progressed.
Electrolyte: On the basis of the predecessor project baseline, new high-voltage stable solvents, co-solvents and electrolyte salts were proposed and tested. As a result, iteration-1 electrolyte has been proposed.
Cathode active material (LNMO): After a thorough physico-chemical material characterization of different candidate materials, the morphology was identified as a decisive differentiator between the candidates. Following formulation and casting trials, one of the candidates has been selected as iteration-1 LNMO (following also the scale-up trials).
Scale-up. With the selected materials, electrode coating was performed using larger material quantities on pilot line with doctor blade (using aqueous processing for the cathode). Formulations were adapted to optimize the electrode coating results.
Iteration-0 cells with baseline/reference materials (LNMO cathode, silicon-graphite anode, high-voltage electrolyte) have been built, and testing according to the defined protocols has started.
Multi-layer coating. To reach a desirable balance between energy and power density, utilization of multi-layer electrode coating approach is investigated in HighSpin. Two different approaches (blade coating, with drying and subsequent coating of second layer) as well as slot-die coating (with simultaneous deposition of two different slurries on the electrode foil) have been trialed at two different pilot facilities. While the process was successfully executed, the resulting foils exhibited issues such as cracking of the electrode and lack in flexibility and bending characteristics. Various binders began to be explored to remedy this.
Laser structuring aims to developed optimised electrode architectures on both the cathode and anode side. These architectures should be capable of providing simultaneously high energy and high power density, as well as fast charging capabilities. A promising approach to reach this aim is the implementation of a 3D surface topography realised by a local removal of electrode material via ultrashort pulse (USP) laser ablation on high mass-loaded electrodes.
As a starting point for the task, the USP laser structuring of the LNMO cathode was investigated in detail, as there is no reported data available for this topic. First, ablation studies on LNMO cathodes with different compositions and binders and with varying areal capacities (mAh/cm2) were conducted using a laser material processing system equipped with an advanced high-power USP laser source to analyse the ablation characteristics.
Preliminary results indicate that slight changes in the electrode composition ratios have no large influence on the resulting ablation depth of the laser generated grooves. This result is very promising for the further course of the project, as it can be assumed that in principle the ablation processes and their respective laser parameters can be easily transferred to any LNMO cathode generation with newly formulated composition ratios, as developed in HighSpin.
Aeronautic battery module. One project objective is to design and build a slim-fit, BMS-agnostic aeronautic battery module, as well as to design and assemble corresponding pouch cells for testing.
The aeronautic application requirements into design constraints. This resulted in a specification of the module safety and performance requirements for propulsive and non-propulsive applications. This specification has set a framework for the application of market needs.
A market analysis was carried out by compiling information from multiple real case studies and customer consultations. These use cases have been summarized according to their general needs: voltage; capacity; energy; power. All these real-life cases have been grouped into five categories. The energy / power capability of the HighSpin chemistry has been compared to these five categories of application. The conclusion is that HighSpin chemistry can address both conventional and multicopter applications.
On the materials development level, various LNMO and silicon graphite candidates have been screened, and electrolyte development has progressed.
Electrolyte: On the basis of the predecessor project baseline, new high-voltage stable solvents, co-solvents and electrolyte salts were proposed and tested. As a result, iteration-1 electrolyte has been proposed.
Cathode active material (LNMO): After a thorough physico-chemical material characterization of different candidate materials, the morphology was identified as a decisive differentiator between the candidates. Following formulation and casting trials, one of the candidates has been selected as iteration-1 LNMO (following also the scale-up trials).
Scale-up. With the selected materials, electrode coating was performed using larger material quantities on pilot line with doctor blade (using aqueous processing for the cathode). Formulations were adapted to optimize the electrode coating results.
Iteration-0 cells with baseline/reference materials (LNMO cathode, silicon-graphite anode, high-voltage electrolyte) have been built, and testing according to the defined protocols has started.
Multi-layer coating. To reach a desirable balance between energy and power density, utilization of multi-layer electrode coating approach is investigated in HighSpin. Two different approaches (blade coating, with drying and subsequent coating of second layer) as well as slot-die coating (with simultaneous deposition of two different slurries on the electrode foil) have been trialed at two different pilot facilities. While the process was successfully executed, the resulting foils exhibited issues such as cracking of the electrode and lack in flexibility and bending characteristics. Various binders began to be explored to remedy this.
Laser structuring aims to developed optimised electrode architectures on both the cathode and anode side. These architectures should be capable of providing simultaneously high energy and high power density, as well as fast charging capabilities. A promising approach to reach this aim is the implementation of a 3D surface topography realised by a local removal of electrode material via ultrashort pulse (USP) laser ablation on high mass-loaded electrodes.
As a starting point for the task, the USP laser structuring of the LNMO cathode was investigated in detail, as there is no reported data available for this topic. First, ablation studies on LNMO cathodes with different compositions and binders and with varying areal capacities (mAh/cm2) were conducted using a laser material processing system equipped with an advanced high-power USP laser source to analyse the ablation characteristics.
Preliminary results indicate that slight changes in the electrode composition ratios have no large influence on the resulting ablation depth of the laser generated grooves. This result is very promising for the further course of the project, as it can be assumed that in principle the ablation processes and their respective laser parameters can be easily transferred to any LNMO cathode generation with newly formulated composition ratios, as developed in HighSpin.
Aeronautic battery module. One project objective is to design and build a slim-fit, BMS-agnostic aeronautic battery module, as well as to design and assemble corresponding pouch cells for testing.
The aeronautic application requirements into design constraints. This resulted in a specification of the module safety and performance requirements for propulsive and non-propulsive applications. This specification has set a framework for the application of market needs.
A market analysis was carried out by compiling information from multiple real case studies and customer consultations. These use cases have been summarized according to their general needs: voltage; capacity; energy; power. All these real-life cases have been grouped into five categories. The energy / power capability of the HighSpin chemistry has been compared to these five categories of application. The conclusion is that HighSpin chemistry can address both conventional and multicopter applications.
The expected technical results include:
Materials: LNMO cathode with 3.0 g/cm3 density and anode with 20 wt. % of Si (730 mAh/g capacity). Stable electrolyte up to 5.0V.
Processes: Ultrafast 3D electrode multilayer coating and laser structuring speed of ≥ 5 m/sec.
Demonstrators: LNMO cells at 390 Wh/kg and 925 Wh/l at a cost target of 90 €/kWh (pack level). 300 cells/150 CMUs produced, and 2 module demonstrators delivered at TRL 6.
The potential impacts include a performant, Co-free Li-Ion cell with a good balance between energy density and rate capability (resulting from multilayer coating and laser structuring) and that can be produced with existing manufacturing equipment and processes at an attractive target cost. If successful, this materials selection and design could be a basis for further development with a view to gigafactory-scale production. The environmental profile of the cells (Co-free and lower Ni content vs. comparable NMC-based cathodes, as well as aqueous processing of electrodes) could result in a reduction of the environmental impacts of battery production based on this chemistry.
Materials: LNMO cathode with 3.0 g/cm3 density and anode with 20 wt. % of Si (730 mAh/g capacity). Stable electrolyte up to 5.0V.
Processes: Ultrafast 3D electrode multilayer coating and laser structuring speed of ≥ 5 m/sec.
Demonstrators: LNMO cells at 390 Wh/kg and 925 Wh/l at a cost target of 90 €/kWh (pack level). 300 cells/150 CMUs produced, and 2 module demonstrators delivered at TRL 6.
The potential impacts include a performant, Co-free Li-Ion cell with a good balance between energy density and rate capability (resulting from multilayer coating and laser structuring) and that can be produced with existing manufacturing equipment and processes at an attractive target cost. If successful, this materials selection and design could be a basis for further development with a view to gigafactory-scale production. The environmental profile of the cells (Co-free and lower Ni content vs. comparable NMC-based cathodes, as well as aqueous processing of electrodes) could result in a reduction of the environmental impacts of battery production based on this chemistry.