Michael Ross via EV wrote:
I am not sure about previous discussions and you may know this: Peukert's Law is not applicable to Li ion cells in any way. It only relates to lead acid cells.
I agree with the rest of what you said, but not with this. Peukert's law says nothing about the chemistry involved; it applies to *all* types of batteries and all chemistries.
Peukert's equation applies to any battery or cell that has internal resistance, and that has a minimum "cutoff" voltage below which it is harmed. It simply states that the higher the load current, the lower the apparent amphour capacity. High currents cause a larger voltage drop, so you reach the "cutoff" voltage before the cell is truly dead.
The amphours are not "missing"; you just can't get them without reducing the load current, or pulling its voltage below the safe minimum. If you're willing to shorten the life of the cell, you can still get it.
Peukert matters more for lead-acids because they typically have a higher internal resistance. In particular, lead-acid internal resistance goes up a lot as the cell approaches dead. Most other chemistries do not have this large change in internal resistance as a function of state of charge.
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