If I were to guess, this issue will be because metal tabs inside the cells were cut to shape with a stamping machine. The stamping machine die was probably worn, leaving burrs on the edges of the tabs. Those burrs are sharp and perforate plastic membranes, causing a short.<p>Lesson:. All stamped parts should be deburred.
>Due to SK Cells<p>I predicted Ford would have problems with SK batteries two years ago the moment Bolts started going up in flames <a href="https://news.ycombinator.com/item?id=28547711" rel="nofollow">https://news.ycombinator.com/item?id=28547711</a> :<p>>you will be happy to know Ford is using SK batteries after switching away from LG. SK just recently settled for $2billions a case that revealed they stole LG battery technology. Bolt uses LG batteries.<p>>LG had a chain of costly recalls and replacements for all of their clients<p>>"LG Energy Solutions, the company that makes the battery for the Bolt and Kona EV, has not had a good year. First, they agreed to replace the 82,000 batteries sold to Hyundai for the Kona EV, Ioniq, and Elec City buses. Although the initial rumors were from a faulty battery separator, Hyundai later said that the problem was badly folded tabs. GM emphatically pointed out that they use a different separator, and a different factory. Thus neither of those problems should apply to the Bolt fires.<p>>Porsche recently initiated a recall on a loss of power in its Taycan LG batteries, and Ford also moved from LG in its Mustang Mach-E to SK in its Ford F-150 Lightning."
Aren’t really large batteries still a fire hazard. I remember when they even became issues for Boeing Dreamliner planes:<p><a href="https://en.m.wikipedia.org/wiki/2013_Boeing_787_Dreamliner_grounding" rel="nofollow">https://en.m.wikipedia.org/wiki/2013_Boeing_787_Dreamliner_g...</a>