Charging power vs state-of-charge (SOC)

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CivilJeep

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...the warranty is only obligated to replace enough components/modules to restore the battery health to that level, not replace the entire pack. Obviously circumstances vary and some packs are replaced entirely if the cells cannot be collectively brought back into spec/voltages balanced. Now the $64 question is what is Ford's measuring stick for these batteries?
Question for those more in the know on battery packs than I am ....would Ford (or any manufacturer) be able to unlock the "buffer" capacity of a battery to avoid the warranty claim of battery degradation?
 

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Question for those more in the know on battery packs than I am ....would Ford (or any manufacturer) be able to unlock the "buffer" capacity of a battery to avoid the warranty claim of battery degradation?
Yes, it is just a setting in the car, so the expectation is that Ford (and others) will gradually widen out the buffer to maintain capacity over time. This is the same strategy we use in stationary grid storage - start with a large buffer and gradually reduce it to compensate for degradation.
 

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Question for those more in the know on battery packs than I am ....would Ford (or any manufacturer) be able to unlock the "buffer" capacity of a battery to avoid the warranty claim of battery degradation?
Yes, it is just a setting in the car, so the expectation is that Ford (and others) will gradually widen out the buffer to maintain capacity over time. This is the same strategy we use in stationary grid storage - start with a large buffer and gradually reduce it to compensate for degradation.
Sort of. If there is spare buffer on the bottom end - ie they report the battery at 0 when it has 5kwh left - then that could be opened up a little. BUT, discharging Li-ion too low can quickly damage the battery badly, so it would be a short-lived "fix" if they opened up too much on the bottom.

Keep in mind the the "top" buffer isn't really "spare". The top buffer limits how much of the maximum each cell in the pack gets charged. Once the cells can no longer take a charge up to that proportion of the total then the upper buffer is "used up", even if you never actually charged the cells to their maximum.

A mediocre analogy is a water pitcher that has a tiny crack running 1% of the way down from the top. As long as you only fill it 90% of the way, you never notice that the pitcher has that crack. Over time the crack grows longer until it runs 11% of the way down from the top, so you can't fill it as much as you used to because the water leaks out when you do. You can't suddenly use that extra capacity from all those previous times you only filled it to 90% - you are forever limited to using no more than 89% of the pitcher's volume.

And of course over time the crack gets longer, and thus you are only able to store less and less water in it.
 

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