Quote:
Originally Posted by redpoint5
Yes, but the void space is filled with cooling fluid which may prevent a single cell failure from causing its neighbor to ignite. Just a theory anyhow.
How many tesla fires have been spontaneous rather than a result of crash? Of course we need to keep in mind there are many more Teslas in the wild than Chevy EVs, so the fires per 10,000 units are much higher for GMs EVs.
I was very critical of Tesla's decision to go cylindrical as well, but now I'm not so sure. Their larger format ones may end up being a good "all things considered" approach.
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Yes, Teslas have had battery fires while sitting or charging. Here is one from the USA
https://www.washingtonpost.com/techn...04/tesla-fire/
And one from China
https://www.cnbc.com/2019/04/22/tesl...-shanghai.html
I don't know the total number and I really doubt Tesla is making that data public nor do I want to get into a discussion fires per 100,000 vehicles. My point was simply using cylindrical cells and wrapping them with a cooling ribbon doesn't safeguard Tesla from battery fires.
It is possible to build a battery with prizm cells and seperate each one with a cooling plate. The Volt battery (and Spark) were built that way.
From GM:
"The Dana Corp-manufactured cooling fin consists of two lightweight aluminum plates joined by a proprietary clean nickel-brazing process. The carefully designed grooves stamped into the plates form channels that allow battery coolant that is pumped through the pack to flow over the entire cell surface."
https://media.gm.com/media/us/en/gm/...4_battery.html
The Bolt replaced that cooling plate with an aluminum plate that acts as a heat sink connected to a liquid cooled heat exchanger below the battery cells. Here is an excellent tear-down video of the Bolt battery (he has one for the Volt as well)
To date GM has seen 12 battery fires in stationary vehicles out of 141,000 built. That is not an acceptable number but it puts the risk to current owners is perspective.
There is another huge difference between a Chevy battery and a Tesla Battery. Because the Chevy battery is bolted together instead of glued, GM is able to repair the batteries instead of replacing the entire pack.
"GM said Monday that it would start shipping new battery cells to dealerships as early as mid-October to begin replacing potentially faulty battery modules."
Image the cost if Tesla has to replace every battery in a Model 3 because of some tiny internal manufacturing defect.