@DavidHowey we used acoustics to measure the rate of pouch cell gassing due to changes in temperature (solid/gas interfaces attenuate sound significantly), there's a clear linear relation to how much the increase the temp: https://t.co/Xb4FuJn5ON
Failure modes due to "dead Li" are not well understood. I mentioned our work (https://t.co/IKnVFWqi3i) (s/o @wesleykchang/@CBommier/@ShripPatil) that discusses a gassing risk of these cells. We didn't push these to runaway b/c safety, but I'm curious …
Not to say it can't happen! This is a big cell, and we're talking a 1 in 100,000 type event even with this much Li. But a mechanism we have seen that is more likely to cause catastrophic damage is indicated in that paper (https://t.co/9EVQssSQPr). 6/n
That is a crazy amount of Li in that picture. Over the last few years we've tested and abused 1000(? likely more) cells and the only way we've seen this much lithium at currents this unit saw were if the cells were too _cold_ and charged too quickly. h…