The ECO COM'BAT project team adapted and optimized ORMOCER® coated, low-cobalt NMC 622 and a special high-voltage electrolyte based on the conductive salt lithium-bis(fluorosulfonyl)imide (LiFSI), which can be operated stably even at high voltages, to the battery requirements. This led to approximately 20 percent reduction of cobalt content and a reduction of electrolyte fluorine content by two thirds. At the beginning of the project, the ECO COM'BAT materials and the corresponding production processes had been at TRL 5. Through the project activities, the materials are now at TRL 7 and have been produced in pilot batches of up to 20 kilograms.
The upscaling process comprised the following work packages:
- High-voltage electrolyte with lithium salt LiFSI (latest development of Arkema) to ensure safety and long lifecycle
- Sustainable and high energy active materials with low Co content (NMC 622 of Umicore) and functional protective coating (ORMOCER® – trademark of Fraunhofer) to reach high energy density (long range) and long cycle life
In addition, the structured carbon additives Porocarb® and Graphistrength® were applied to further increase the energy and power density of the battery cells.
Specific combination of innovative carbons used in the project:
- Carbons with specific porous structure as pore former (Porocarb® - trademark of Heraeus) to reach good compaction and thus high energy density (long range)
- Carbon nanotubes as conductive additives (Graphistrength® - trademark of Arkema) to increase conduction performance and thus high-power density (fast charging)