I know this isn't exactly related but here is the
report from a 2019 battery storage explosion here in Arizona. It's a very detailed report although they are using Lithium-Ion batteries instead. It's still interesting to read about a battery storage systems built by smart people and backed by millions of dollars can still explode.
One thing they noted was thermal runway of one cell caused other cells to heat up due to lack of a thermal barrier between cells. One bad cell could cause others to vent as well due to the heat transfer to next cell.