Battery Draw Bogus Math? Peukert UPDATE 2
Update- 11 Oct 20, Update 2- 12 Oct 20 Thinking one 100AH battery that can be drawn down to very low SOC gives you nearly the same "usable AH" as two regular AGM or Wet batts, as seen advertized, ...
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I don't follow at all. My claim is that the "same" 80AH actually is about three times more time at 5 amps when the 20 hr rate is 10 amps.
EDIT--have to correct from 16 to 8 hours at 5 amps for the 200AH bank
With the one 100AH batt down to 20 you got 16 hours at 5 amps.
With the two 100AH in parallel down to 60 each, you get 8 hrs (not 16!)--but at 10 amps,
Apparently you would get 3 x 8 = 24 (corrected from 48) hrs if you ran them down to 60 each at 5 amps on the bank. But that is not 80AH anymore either!
I was looking at how my one SiO2 would do almost as much low amp running time as the two 27s do, based on AH as they advertize. But then my BS warning light came on. Hmmmm.
I just think the way they play with "usable AH" amounts to false advertizing they way I look at "use". "Use" to me is a draw for a certain time. They should use the same "use" for "usable" in each case.
A Carny Barker must have thought up "usable AH" :)
EDIT--have to correct from 16 to 8 hours at 5 amps for the 200AH bank
With the one 100AH batt down to 20 you got 16 hours at 5 amps.
With the two 100AH in parallel down to 60 each, you get 8 hrs (not 16!)--but at 10 amps,
Apparently you would get 3 x 8 = 24 (corrected from 48) hrs if you ran them down to 60 each at 5 amps on the bank. But that is not 80AH anymore either!
I was looking at how my one SiO2 would do almost as much low amp running time as the two 27s do, based on AH as they advertize. But then my BS warning light came on. Hmmmm.
I just think the way they play with "usable AH" amounts to false advertizing they way I look at "use". "Use" to me is a draw for a certain time. They should use the same "use" for "usable" in each case.
A Carny Barker must have thought up "usable AH" :)
