On Jul 26, 11:04*pm, Larry wrote:
GeoffSchultz wrote in news:df328769-b664-
:

it's charging my (2) 8Ds quickly.

Sorry......as this is chemically impossible. *25A is more than enough to
charge a pair of 8Ds at their normal rate of charge.

A 100A charger is NOT going to put out 100A on these batteries for more
than a few minutes! *Lead acid batteries just don't charge like that.

Sorry, but years of actual experience with these batteries argues with
your statement. Also, I've had extensive e-mail conversations with
the engineer responsible for the design of these batteries and he also
would disagree with you. According to Caterpiller, who makes my
153-5720 batteries, the charging rate should not exceed 5% of the CCA,
which is 1500 A per battery. That 3000 CCA total or a max charging
rate of 150A.

I have a display that shows the numeric charging rates and I see the
charging rate start out at ~110A and then rapidly drops down once the
charging voltage reaches 14.2V. It easily takes 45 minutes or more
before I see the charging rate drops below 25A. If you spend you life
ties up to shore, 25A is probably a fine charging rate. However, when
cruising and charging off of a generator, that wouldn't work. Also
considering that I've gotten 5 years out of these batteries and
they're still running fine, I'm happy and think that I haven't damaged
them by my charging regiment.

-- Geoff