Tesla Inc (TSLA)

[boston745]

On March 21 2021 a Tesla owner describes what appears to be the beginning of a thermal runaway event. Fortunately it didnt ignite the whole car:

30 seconds later I start smelling a toxic electric smell. Was warmish in Chicago so I had sunroof open. Couldn’t tell whether it was me or I was downwind of something or some other car, but yet smell was definitely there. 30 seconds after that I received the following alert at bottom of cluster, “Car may not restart; contact service”. . . Uh oh.

Kept driving, and 30 seconds more, about quarter mile to my destination I had what can only be referred to as an “Apollo 13” moment. Everything started beeping, alerts in rapid succession started filling my infotainment screen. Maggie started shutting all systems down 1 at a time but 100 alerts popped up in seconds. It was intense and chaotic. As I pulled into destination, I lost power steering, the accelerator stopped responding and I luckily coasted into the parking lot and rolled to a stop. I intentionally parked away from everyone because I thought I might be calling the fire department.

Based on what occurred here it looks like BMS caught the problem in the early stages of thermal runaway and prevented a worse scenario.

When lithium-ion batteries begin to fail, the chemical process produces electrolyte vapour from battery cells. This off-gas is produced soon after cell damage occurs and several minutes before thermal runaway starts. 

Lithium-ion battery failure eventually produces detectable smoke, too, but only after thermal runaway has already begun. Detecting smoke alone results in a response that is too late. Instead, by detecting the presence of off-gases, affected batteries can be shut down in time to prevent thermal runaway

Like the Tesla Plaid & Chevy Bolt fires, this thermal runaway event happened during a solar storm & geomagnetic unrest:

https://spaceweather.com/archive.php?view=1&day=21&month=03&year=2021

In charting trends you want at least 3 points, well this is a third. Of course I have many more to add to this trend.