There have been at least two fires.
The guy from Asia who sat on his battery and suspects most of his weight pressed on one high terminal which might have caused damage and an internal short.
Then there is this fire of florst’s where she suspects mice/rodents might have caused a short or a wire coming loose or whatever.
As I said earlier, it really doesn’t matter.
Whether from pests, poor connections that come loose, or internal shorts resulting from dendrite growth, the bottom line is that the BMSs (and fuses) we all use do a pretty good job detecting and protecting against excessive battery discharge / short, but do nothing to detect and protect against an internal short (other than shutting down when a cell discharged to LVD if the discharge rate is slow enough).
Especially in this era of the Chevy Bolt (‘don’t park in the garage, park 50’ away from any other vehicle’), I’m surprised to see this subject being dismissed as quickly as it is.
Fire can only result from above-normal temperatures and monitoring battery temperature and even individual cell temperatures is not only easy, but relatively inexpensive.
If we conclude that a reliable precursor of a combustion event must always be enough heat to warm up adjacent cells to the point they bloat and create clamping fixture pressure outside of the normal range, that’s an even easier and cheaper thing to monitor at the whole-battery level.
Of course, if we know that the risk of a cell failure / internal shorting even is <0.01%/year, each of us can decide whether we’re comfortable with that level of risk or want to take additional steps to protect against it.
That’s not the point.
The point is are there any reliable precursors to combustion events escaping detection by BMS and fuse that can be used to add additional levels of protection?