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Re:Lithium metal batteries with diluted high concentration e... by mc32 on Friday November 12, 2021 @08:46AM (#29199179)
It does not require specialized equipment, but it does require a lift --which few people have in their garage, and you have to remove all the seats. But to be fair, swapping out an ICE engine is even more work/difficult. On the other hand, one bad cell means you have to pull out the whole battery pack to replace the single deflective cell.
Re:Lithium metal batteries with diluted high concentration e... by db48x on Friday November 12, 2021 @09:25AM (#29199522)
You probably won’t be able to do the job in an hour without a lift, but you _can_ use just ordinary jacks. Certainly every car shop on the planet has the tools to do it; they won’t have to buy anything specialized from Tesla.
Re:Lithium metal batteries with diluted high concentration e... by mc32 on Friday November 12, 2021 @09:45AM (#29199712)
One Tesla tool they need —which Tesla released— is diagnostic sw to help ID the bad cell(s), else it would take longer to find a bad cell among ~1,500 of them.
Re:Lithium metal batteries with diluted high concentration e... by mcot2 on Friday November 12, 2021 @11:10AM (#29200790)
Tesla just replaces whole packs now. They might have a tool to diagnose a bad battery but they don’t replace modules, they only replace entire packs.

As such their next gen pack is a single structural member of the car and likely will not be replaceable at all.

Re:Lithium metal batteries with diluted high concentration e... by db48x on Friday November 12, 2021 @11:15AM (#29200864)
As I understand it, neither of those statements are exactly true.

Tesla replaces battery packs and then sends the old one back to the factory to be refurbished, rather than junked.

As for future designs, a structural battery pack would still be replaceable. The difference is that the battery pack would supply a portion of the strength and rigidity of the frame. That doesn’t mean the car would fall apart if you removed it, however.

Re:Lithium metal batteries with diluted high concentration e... by db48x on Friday November 12, 2021 @11:11AM (#29200805)
That’s true if there are a small number of bad modules that you want to replace, but not really relevant if you’re just going to swap a new battery into an old Tesla.
Re:Lithium metal batteries with diluted high concentration e... by ianai on Friday November 12, 2021 @08:57AM (#29199274)
But the battery management system automatically disables bad cells so you wouldn’t need to replace an individual cell.
Re:Lithium metal batteries with diluted high concentration e... by mc32 on Friday November 12, 2021 @09:07AM (#29199356)
People seem to have a different experience. See here: https://electrek.co/2021/09/13/tesla-battery-pack-replacemen...
Re:Lithium metal batteries with diluted high concentration e... by jacquesm on Friday November 12, 2021 @10:33AM (#29200242)
There are different models of Tesla packs in circulation.
Re:Lithium metal batteries with diluted high concentration e... by kwhitefoot on Friday November 12, 2021 @10:05AM (#29199913)
That seems really unlikely, or impossible. The 18650 cells in a Tesla Model S are only about twice as big as an AA and they are grouped in parallel blocks that are then connected in series. There does not appear to be any way of isolating a specific cell.

Each module has six groups of cells in series, 74 in parallel in each group, giving a module voltage of 22.8 V.

See https://www.researchgate.net/figure/Tesla-Model-S-74p6s-Batt...

Re:Lithium metal batteries with diluted high concentration e... by jacquesm on Friday November 12, 2021 @10:33AM (#29200233)
Newer Tesla batteries are fused per cell, so when a battery dies and it's neighbor cells start dumping charge into it the fuse goes and hopefully that's that. So it's perfectly possible for a single battery to become disconnected from the rest of the pack. But that's not a function of the battery management system, it's purely a safety feature (otherwise the pack would almost certainly go up).