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Old 05-28-2014, 12:13 AM   #4 (permalink)
herp derp Apprentice
Join Date: Oct 2008
Location: Lawrence, KS
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Originally Posted by redpoint5 View Post
Some sources place charging efficiency for lead-acid as low as 50% when charging near full capacity.
Is this main place where gains are to be had, once the engine is running, battery recharged, accessories running off the alternator... Is the battery just sitting there suckin up the extra voltage just turning it into heat?
Last I read up on newer gm's charging systems, when the charging system is in fuel economy mode, the output voltage is targeted at what it thinks the open circuit voltage of the battery is. Didn't give it much thought previously, but I guess gm's strategy is to try to leave the battery out of it as much as possible.

Also, any thoughts to if an AGM battery might outperform a lead acid in this respect on an older vehicle due to its slightly higher voltage?
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