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A comment on Podswap: Keep airpods alive and out of the landfill. Parent comment

Re:Podswap: Keep airpods alive and out of the landfill by aetherspawn on Sunday July 11, 2021 @11:59PM (#27806891)
Ex EV battery engineer here. You’re right that the cycle life of a lithium battery typically doubles per 0.05V (‘tik’) undercharged from 4.15V (and on the other end of the scale as well, less so).

This typically corresponds to around 7-10% capacity per ‘tik’, so to effectively triple your battery cycle count would reduce the runtime by approximately 30%.

Interesting effect here.. the amount of power in each cycle is less because you’re undercharging the battery. And for each consecutive ‘tik’, 0.05V is approximately more power because the discharge curve becomes flatter (voltage != state of charge). It doesn’t scale like you’d think. Seriously diminishing returns!

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Re:Podswap: Keep airpods alive and out of the landfill by justnotworthit on Monday July 12, 2021 @02:46PM (#27813608)
Could you tell me if the "under X%" claim is true about battery? I saw an old study that didn't seem to be affected by how low the charge got, just heat (fast charge) and time spent charging over 80%.
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