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ekr 3 hours ago

Although the thought of getting an electric car has passed through my mind on a few occasions, I'm not 100% familiar with the intricate technical details. (for some reason, the tax incentives where I live are still in favor of continuing with the small petrol car I have. Taxes are primarily a function of weight in the Netherlands, and anything besides a lightweight Dacia Spring would imply significantly higher monthly expenditure for me).

What I'm wondering w.r.t. this article is: wouldn't such fast charging shorten the battery lifespan?

I have experience with ebike batteries. Bosch in particular, with very decent 29E samsung cells, that after 70k km or so, basically halved their capacity. I imagine this effect is severily reduced with a car battery because there are a lot more than 10p, so all the wear is distributed more evenly, and 29E are very old technology.

Toutouxc 2 hours ago | parent [-]

I believe you meant to write “10S” instead of 10p. I’m not 100% sure, but you were talking about e-bike batteries, which are often 36V, made out of 10 cells (or banks of cells) in series. The nominal voltage of most lithium chemistries is 3.6-3.7V.

EV batteries have many more cells in series, for example my car is 104S, and 800V cars have (obviously) more than 200 cells in series.

And the longevity of car batteries isn’t about wear being distributed “evenly” (a healthy battery can’t really wear “unevenly”, you always load all cells at once). EVs take care of their batteries, they cool them, heat them, balance them periodically, and they don’t actually pull that much power from them. They also keep the cells within pretty conservative voltage limits.

ekr 40 minutes ago | parent [-]

Indeed, I meant 10S. And what I meant by load being distributed along more cells, is that since you have many more cells, current drawn from each is lower. Which greatly prolongs the lifetime.

And hence the question I had with charging too fast. Since discharging faster clearly wears them more quickly, surely charging faster has a similar effect, since it's mostly the reversed process? A question probably easily answered with a query to a LLM.