Re: Even more homebuilt charger madness

[Lee Hart <leeahart@earthlink.net>]

Victor Tikhonov wrote:
> 
> I can see the advantage of sitting on each battery slightly different
> time based on its SOC, but please explain their other claim: for 10
> batteries if you charge each for say 1 min at 30A and have to make
> 9 min pauses (10% duty), that's the same Ah rate as at 3A continuous
> charge (100%). How come the total charge time is less?

When you are well away from 100% SOC, battery amphour charging
efficiency is essentially 100%. It won't matter if you apply 30 amps 10%
of the time or 3 amps 100% of the time. It will take the same number of
amphours to recharge.

But, the last 20% or so of a charge (as you go from 80% to 100% SOC) is
significantly less efficient. If's possible that pulsing the charging
current on/off keeps the average battery voltage a bit lower, and so the
charging efficiency a bit higher.
-- 
Lee A. Hart                  Ring the bells that still can ring
814 8th Ave. N.              Forget your perfect offering
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leeahart_at_earthlink.net    That's how the light gets in -- Leonard
Cohen