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This efficiency doesn't translate to EV battery packs. They require thousands of welds, the pack contains ends up with plenty of empty space and it's impractical to replace parts of it.

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For LFP you can supposedly pack the cells very tight, as they require less thermal management if I understand correctly. And you’re HAVE to do this optimisation for LFP to have decent pack level energy density.

For Li-ion cells, you need that empty space for cooling of the battery cells anyway.

And Tesla has demonstrated that cylindrical cells can contribute to the structure in a structural battery pack.

So for Li-ion I don’t think cylindrical cells are worse. There’s just different trade-offs.

But yeah, one of downsides it can be hard or impossible to replace individual cells if they have problems.

It doesn't matter how much you "pack the cells very tight", there's a geometrical limit here.[1]

And in practice, you'll have modules of sections of the battery for repairing which drops the efficiency to below 90%.

[1] https://en.wikipedia.org/wiki/Circle_packing#Densest_packing

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