AGM Batt on Trickle Charge?
I recall that AGM batteries are a bit different somehow, so I'd like to know what to expect. I'm thinking of getting a solar setup for tent snow camping. A Powerfilm 60w flexible panel/tarp, and a...
Forum Discussion
greenrvgreen wrote:
1. How far down can I deep cycle an 18ah AGM, and how many times, before it goes T/U? Here's the one I'm looking at:
http://www.amazon.com/UPG-UBCD5745-Sealed-Lead-Batteries/dp/B001DL7D1O/ref=sr_1_1?ie=UTF8&qid=1398366935&sr=8-1&keywords=upg+18ah
2. Using the 6- or 12-amp charger linked earlier, could I hook one to my car battery and leave it unattended overnight? And without ever running the engine, can I expect enough juice left in the ~85ah car batt?
1) Good brand, former Panasonic, China have bought it. I wouldn't go below 60% SOC, i.e. you can take no more than 7 AH out of it. It won't die same day if you do, but the life and capacity will shorten.
2) Yes, overnight. And yes, it will keep the car battery where you left it and will add a little, if there is any sun. Meaning, if there was 70% before, it will raise it to 90-ish in a day or two. If there is a heavy blizzard for 3-4 days, it won't even keep it at 70. Like others noted, for only car battery maintenance (meaning - preventing self-discharge but not raising the charge), 60W is an overkill.
Unisloar is not a half of Powerfilm cost. $150 for 68W Uni and $700 for 60W Power tarp.
6A or 12A charger with 68W Unisolar: I think 12A. 68W Uni has 5.1A current, so 6A is enough, even with recommended 20% margin. But if you go up in the mountains, and/or in cold weather, the current can be higher.
In Powerfilm tarp they already included some controller.
