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A comment on Tesla's giant battery saved $40M during its first year, report says. Parent comment

Re:Tesla's giant battery saved $40M during its first year, r... by mschuster91 on Thursday December 06, 2018 @02:28PM (#18621224)
> My car is almost four years old and its battery has lost about 1% capacity. These things don’t wear out that quickly.

Probably because Tesla undersells their batteries. During hurricanes or other disasters Tesla routinely unlocks the software limit, allowing customers more range (https://www.teslarati.com/tesla-unlocks-full-battery-capacit...).

It's the same with HDDs and SSDs, which always carry a decent safety margin to account for media wear.

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Re:Tesla's giant battery saved $40M during its first year, r... by mikeash on Thursday December 06, 2018 @02:30PM (#18621244)
Only certain models are software limited, and the 85 isn’t one of those. They actually substantially overstated the capacity: the 85 means 85kWh, but the actual usable capacity is only about 77.5kWh. (https://electrek.co/2016/12/14/tesla-battery-capacity/)
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Re:Tesla's giant battery saved $40M during its first year, r... by rightbyte on Thursday December 06, 2018 @04:17PM (#18622325)
The SoC window is not 0 to 100%, it's might be eg. 15 - 75 % or something. That's also why you don't notice battery degradation, since the window might be moving (keeping constant energy limits for 0 and 100% charged).

For kWh capacity it's just a matter of counting the cells. Actual kWh will vary abit by measuring technique but I assume there is a way to drain the nominal Wh:s from them.

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