Ok, so we hear a lot about how Peukert's law "steals" from us when we misbehave by applying loads anywhere above what our batteries can deliver at C/20. Then some say Peukert rewards us with an extra 33% of so if we are content with discharging at as little as C/100.
But what about conservation of energy?
If you have put 120 AH of your PV's hard-earned power into a 100AH battery to account for losses to ensure a 100 SOC then what happens to the rest if you happily disharge it to zero in only 18mins at 1C? You have only removed about 30AH from the battery in energy terms. Did the rest get converted into heat or some other form of energy? What about when you carefully remove 130AH from the battery at C/100? Was that extra 30AH a free gift from the energy Gods as a reward for being frugal???
I somehow doubt it. Energy cannot be created or destroyed. My logic tells me that discharging a battery at 1C over 18mins does not yield a 0% real state of charge. It has simply produced an apparent 0% SOC at the plates, which given enough time to rest would yield a 60% SOC once the electrolyte has had time to diffuse. Also a slow discharge at C/100 for 130 hours would surely kill a battery for good as that implies absolutely all of the chemical energy has been removed from the battery. That extra 30AH is what I would call "emergency reserve power" that should never be used under any circumstances if you value your batteries life...
But what about conservation of energy?
If you have put 120 AH of your PV's hard-earned power into a 100AH battery to account for losses to ensure a 100 SOC then what happens to the rest if you happily disharge it to zero in only 18mins at 1C? You have only removed about 30AH from the battery in energy terms. Did the rest get converted into heat or some other form of energy? What about when you carefully remove 130AH from the battery at C/100? Was that extra 30AH a free gift from the energy Gods as a reward for being frugal???
I somehow doubt it. Energy cannot be created or destroyed. My logic tells me that discharging a battery at 1C over 18mins does not yield a 0% real state of charge. It has simply produced an apparent 0% SOC at the plates, which given enough time to rest would yield a 60% SOC once the electrolyte has had time to diffuse. Also a slow discharge at C/100 for 130 hours would surely kill a battery for good as that implies absolutely all of the chemical energy has been removed from the battery. That extra 30AH is what I would call "emergency reserve power" that should never be used under any circumstances if you value your batteries life...
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