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Toyota is recycling old EV batteries to help power Mazda's production line

(www.thedrive.com)
304 points computerliker | 1 comments | 23 Aug 25 18:29 UTC | HN request time: 0s | source
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pornel ◴[27 Aug 25 18:50 UTC] No.45043480[source]▶
Those who TL;DRd - it's for the factory, not the cars!

Old EV batteries are great for energy storage. A worse weight-to-capacity ratio doesn't matter for batteries sitting on the ground. A battery that holds only 70% of its original capacity is considered worn-out for EVs (and even replaced under warranty), but grid storage isn't driving anywhere, so any capacity left is still useful.

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whatever1 ◴[27 Aug 25 18:56 UTC] No.45043554[source]▶
At the cell level they don’t degrade linearly. First it’s slow then it’s fast and then it’s abrupt collapse. You probably have noticed that yourself with old devices. Some do not hold charge even for a minute.

With battery packs probably you can do some smart things to make the degradation curve look more linear, but again there is only so much you can do.

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jama211 ◴[27 Aug 25 19:17 UTC] No.45043818[source]▶
There’s quite a lot you can do when you can isolate and deactivate individual cells, big battery packs like this really do not fall off a cliff in the same way you’re describing.
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carlhjerpe ◴[27 Aug 25 19:40 UTC] No.45044118[source]▶
How do you achieve this with cells in series? Do you kill an entire row and put it on "maintenance voltage"? I know how balance charging RC batteries work but they're smaller scale and "single row".

Also in RC car world it's generally preferred to have one cell per voltage step, I've had way more dual-cell(per series) packs fail than single ones. Though my experience is only 6s/~22v but it's "the same shit on a bigger scale" as far as I can comprehend.

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1. jama211 ◴[28 Aug 25 09:07 UTC] No.45050030{3}[source]▶
I don’t know to be honest, I just know that you can find second hand car batteries that have been used for 15/20 years that still have 40% charge and I don’t know of any single phone battery that’d be the same. I could be talking out of my ass but that’s what I thought.