Making sure disabled EVs are truly de-powered

Electric vehicles are free of tailpipe emissions thanks to a strong current of electricity that flows from the onboard battery pack to the electric motor. But that current, which also powers the onboard systems, could be deadly to emergency workers or occupants if the vehicle becomes disabled in a collision. That's why EVs need a battery interrupter so the current can be instantly turned off and the vehicle is no longer electrified. Halting the current is vital to protecting rescuers and also other electrical systems in the car. One such technology, called the Pyrotechnic Battery Disconnect, is being produced by Detroit supplier Joyson Safety Systems. The component is a small, cylindrical piece that, when activated, drops through the bus bar that conducts the electricity from the EV's battery pack to break its current. In a fraction of a second, the small device can stop between 2,000 and 16,000 amps of current of up to 800 volts. That's enough to cover both EVs and larger commercial vehicle applications in the future.