Join Date: Apr 2006
Thanked 156 Times in 153 Posts
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Re: Battery choice
jeff, AGM is no better or cheaper than wet acid UNLESS you can benefit from the diffferences in the design. AGM can sit over the winter witout being charged, without permanent damage. Wet lead takes permanent damage (irreversible sulfation) if it sits for 30 days without recharging, regardess of charge state. AGM will never eat a hole in your clothing. Wet lead will at any opportunity including the carpet in your car. AGM will cost more than wet lead, but it will cost less than the clothing wet lead ate. Wet lead can be topped up if you overcharge it, AGM can't.
And gel batteries require totally different charging, for most users that's not an option.
Whether you chose wet lead or AGM, if the boat sits a a dock most of the time, a good shore charger will pay for itself by keeping the battery properly topped up but not overcharged. If you can't or don't have that option, hook up a small (20-30W) solar panel with controller and that probably will keep the battery topped up just as well. Keeping any battery properly and fully charged may double the life you get from it, and with battery prices skyrocketing that's good economy.