Senior Moment Member
Join Date: Jun 2011
Location: West Vancouver B.C.
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Re: Battery Sizing - am I crazy?
"I know Deep Cycle batteries are not supposed to be starting batteries"
A common mistake. Deep cycle batteries are supposed to be deep cycle batteries. Starting (SLI) batteries are designed to be CHEAPER batteries with a MORE LIMITED PURPOSE and one special trick, high impulse discharges.
When you build a battery with thick plates, that physically limits how much impulse power those plates can put out, probably due to internal resistanace and heating. When you build lots of thin plates, you can put out lots of impulse power--as an SLI battery does. The problem with thin plates is that traditionally that compromises their physical strength, so they tend to fall apart and break down faster IF they are allowed to weaken (by discharging) in any significant way.
So regular automotive batteries are sprinters and deep cycle batteries are marathon runners?
I, myself, personally intend to continue being outspoken and opinionated, intolerant of all fanatics, fools and ignoramuses, deeply suspicious of all those who have "found the answer" and on my bad days, downright rude.