Quote:
Originally Posted by hayden55
Also, like we saw in the Leaf... cycling small battery packs 100 to 0 will lead to capacity loss much more noticeably and much faster than using a Chevy Bolt the same trip and maybe using 20% of its cycle.
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That can be a fallacious way to look at it however. Any use degrades the battery regardless of depth. I.e., that same 20% used in a Bolt will see a degradation approximately matching that of the 100% use case in terms of raw Amp-hour capacity when ignoring the additional stress of full charges and discharges. It might be more fair to make that comparison against 80% use perhaps.
Regardless, it makes more sense to talk about degradation in terms of amp-hours if you want a way to compare real costs. If you only use 1/4 the capacity but the battery costs 4 times as much, there isn't likely a real savings happening, as that used capacity will degrade similarly across the different pack sizes.
I don't say that to discount the stress of running between full and empty, but if the real world case is 30% depth of discharge vs. 60% for example, a direct comparison of cost per amp-hour likely makes sense if that additional capacity is not going to be needed.
Even so, I know from reading BMWs technical info that the software for the i3 reserves 10% on each end of the charge/use capacity, so it is always running in that middle 80%. I would guess most EVs are similarly setup these days.