Cells in the production-ready EV form factor retained 80% of their original capacity.
StoreDot announced another milestone related to its silicon-dominant anode lithium-ion cells (NCM 811 cathode), designed for extremely fast charging.
The 30Ah pocket battery cells, a production-ready format now available to OEMs around the world for testing purposes, withstood over 1000 rapid charge cycles until capacity dropped to 80% of baseline.
During the tests, the cells were successively charged at a relatively high current (10 minutes), then discharged at a current of approximately 1C (60 minutes). Considering the ambient temperature of 35°C, this is a rather difficult test.
In addition, it should be remembered that these are fairly energy-intensive batteries, with an energy density of 330 Wh/kg and 740 Wh/l (“electrodes and electrolyte only”).
StoreDot’s “100in5” cells were repeatedly charged from 10-80% capacity in just 10 minutes, then discharged for an hour before recharging again. EV cells completed more than 1,000 of these extreme charge cycles consecutively before degrading below the threshold of 80% of original capacity. No appreciable degradation occurred during the first 600 cycles during which the cells were successively charged rapidly between 10 and 80%.
For a theoretical battery of 75 kWh and an initial range of the electric vehicle of 576 km, 1,000 cycles (10-80%) would probably equal more than 362,000 km and the vehicle would still retain 80% of the range: 460 km.
I’m thrilled to report that we not only met our goal, but exceeded it, and we now have an improved formulation in our labs that allows us to show even greater performance. This is the first time that a cell yield of this magnitude has been achieved. The results are a testament to StoreDot’s relentless drive for R&D, the enthusiasm of everyone in the company, and the vision for super-fast charging that we share with our partners.
StoreDot says the first cells (300 Wh/kg and 700 Wh/l energy density) are now shipping to automotive OEM partners around the world, while the company expects further upgrades before the end of this year.
Mass production of “100in5” battery cells will begin in 2024. The long-term goal is to achieve a range recharging speed of 161 km in 2 min.
StoreDot says other form factors other than bag type are also in development: it includes cylindrical type and prismatic type.
More information: www.store-dot.com