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A comment on BMW i3 Long Term Battery Capacity Report: Better Than Expected. Parent comment

Re:BMW i3 Long Term Battery Capacity Report: Better Than Exp... by jessriedel on Saturday April 29, 2017 @09:42AM (#14226548)
Why do we even call "90%" if the battery is disallowed to charge higher for (presumably) longevity reasons? Why not call that "100%"? Assuming I disabled the automatic cutoff at the filling station, I could squeeze a bit more gasoline in my tank by filling the pipe up to the gas cap, but I wouldn't say I'm at 95% for not doing this.

(In contrast, it makes sense to say that the car reports "empty" even when it's at 10%, because you can keep driving it .)

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Re:BMW i3 Long Term Battery Capacity Report: Better Than Exp... by dsfyu404ed on Saturday April 29, 2017 @11:39AM (#14227035)
For discussions of longevity actual capacity is relevant because where the full/empty lines are drawn has a big effect on how much wear and tear gets put on the pack in a cycle. A literal 100% charge is very different than a nominal 100% charge.
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Re:BMW i3 Long Term Battery Capacity Report: Better Than Exp... by jessriedel on Saturday April 29, 2017 @11:59AM (#14227135)
The degree to which each percentage point effects longevity surely varies depending on battery design. It would be a lot more useful it describe it in terms of recharge-discharge cycles than to say "it is limited to charge only up to 90%" and let the listener try to infer what that means about lifetime.
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