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by ggreer 174 days ago
Since this is a discussion about electric vehicles, I thought it could go without saying that I was talking about batteries in such vehicles, not batteries in consumer electronics that are 1,000 times smaller.

To use an analogy: If someone stores a gallon of gasoline in a single-walled plastic container, that's probably OK. But storing 1,000 gallons of gasoline without certain safety measures is unsafe. So it goes with battery capacities.
2 comments
formerly_proven 174 days ago
Apart from Tesla very few EVs ever used cylindrical cells.
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wlesieutre 173 days ago
BMW is moving the other way, from prismatic cells to cylindrical

https://phdenergy.com/beyond-teslas-4680-why-bmws-gen6-4695-...

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ggreer 173 days ago
My point was about cylindrical cells with higher energy chemistries like NMC and NCA. Rivian uses cylindrical cells for their non-LFP batteries. Lucid uses 2170 cells. As far as I can tell, those three (Tesla, Rivian, Lucid) are the only US car manufacturers who have not had battery recalls due to fire risk.

GM, Hyundai, and Nissan all used pouch cells with higher energy density chemistries, and had recalls due to battery fire risks. Ford also recalled tens of thousands of their plug in hybrids due to battery fire risks, though they haven't found a solution yet beyond limiting the max charge of the battery. These batteries are also NMC pouch cells.

I'm sure it's physically possible to make safe, reliable pouch or prismatic cells using higher energy chemistries, but so far it has been risky for those who have tried.

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dark-star 174 days ago
But that's usually just the packaging... if you open that up you'll find... cylindrical cells
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formerly_proven 174 days ago
No?
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vel0city 174 days ago
But it still is untrue even in the discussion of electric vehicles. Tons of EVs have been made safely with chemistries other than LFP with prismatic cells. In fact most non-LFP EV batteries are pouch or prismatic, not cylinder.
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onethought 173 days ago
This isn’t true: “most” non-lfp batteries in EV context are Tesla. Which means they are cylindrical.

Or are you counting OEMs rather than actual vehicles?

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