3 ms·

I'm not very knowledgeable about this, but don't think they fail this gracefully. I thought that a lot of the battery failures in EVs was due to the failures o

I'm not very knowledgeable about this, but don't think they fail this gracefully. I thought that a lot of the battery failures in EVs was due to the failures of individual cells (like AA batteries) within modules, which make it impossible for the BMS to balance power between modules. There was a recent youtube video where an old Model S had its range dramatically reduced to less than 25% because a module had 2 bad cells. The cells were replaced, and the car works as normal now. There was a debate about how long-term that fix would be (eg, would the same thing happen soon, as other cells die).

sokoloff 5y ago
My LEAF had that repair done under warranty (cell #17 was dramatically weaker than the rest, resulting in the pack suddenly having around 33% range and 50% power). Repair was disassemble, change module #9 (cells 17&18), reassemble but took about 2 calendar weeks for parts and trained labor reasons (repair itself was done in a single day). 3.25 years later there is no evidence of recurrence/spread and battery diagnostics are all good. That’s an N of 1, but I don’t see any structural reason to think my battery would now be any different than the sibling car’s battery that was next off the production line (assuming there was no additional fault introduced during service).