Cycling test results of complete prototype-type lithium-ion batteries using graphite producer Mason Graphite’s coated spherical graphite show promising results for electric vehicle applications.
Pouch cells made with graphite in the anode have maintained 86% of their original capacity after 470 cycles of charge and discharge say the Canadian company.
Results were obtained with samples produced at the pilot scale, and not laboratory scale. The batteries were charged and discharged at a rate of C/3 (three hours to charge, three hours to discharge), which the firm says corresponds to the conditions typically used for electric vehicles.
The cathode used for the test was a commercial material of NMC532 type.
The results are promising for use in electric vehicle applications because the prototype cells retain a minimum of 80% of capacity after typically 500 cycles.
The prototype full pouch cell type batteries were assembled on the new prototyping line of NRC in Boucherville, Quebec, Canada, long-term partner of Mason Graphite for the development of its spherical graphite grades, and tested in NRC’s laboratories.
The coated spherical graphite tested was produced at the pilot scale (continuous processing feed capacity of a few tens of kilograms per hour) in the installations of COREM, Quebec, Canada.
Mason Graphite plans a new pilot production campaign of coated spherical graphite in early 2021, which should be followed by a new sequence of cycling tests. The objectives of this campaign are to demonstrate repeatability of the processes, to apply recent optimisation results and to prepare samples for potential customers evaluation.