3 ms·

So in a thermal event, where integrity of the coolant is compromised, you want to dump more heat into the system? Its not just the electrical issues at play, i

So in a thermal event, where integrity of the coolant is compromised, you want to dump more heat into the system? Its not just the electrical issues at play, its the fact that hot battery fluid burns spontaneously with exposure to air (I suspect also water, but I'm less sure about that)

londons_explore 4y ago
A PTC resistor only dumps heat if the system isn't already hot. PTC resistors can be designed which will survive a car fire. It's a good way to ensure that the only way the system can appear safe (ie. cold) is when all batteries are discharged, therefore preventing re-ignition. Obviously you could also have an external energy dump for that purpose (for example power up the cars 5 kw resistive heater for 10 hours), but that's both far slower than boiling water at scale, and won't work after major damage which is likely after a car fire.