When a conventional lithium-ion battery is pierced or severely damaged, a short can occur, discharging the cell in microseconds and potentially releasing a violent and often fiery chain reaction. It’s called thermal runaway and, well, it’s bad. That’s why we created BrakeFlow™, an intra-cell system that increases abuse tolerance.
It wasn’t enough to reimagine the lithium-ion battery, we’ve also introduced a whole new level of safety.
Enovix 3D cell architecture enables multiple parallel cell-to-busbar connections
This uniquely enables BrakeFlow (shown in green) – which includes a resistor with a set value – at the busbar junction
Under normal operation, each electrode carries a small current which results in negligible energy loss
In the event of an internal short, BrakeFlow regulates current flux from other areas of the battery to the short, thus limiting the short area from overheating and inhibiting thermal runaway
Many in the industry use the nail penetration test to simulate an internal short. But not all tests are equal. We used a fully charged cell at 4.35V on our 100% active silicon anode battery on an insulated table, with an impact speed of 20cm/s using a 6cm long steel rod.