Originally Posted by thoer
Anybody else using them who can share their experiences?
I use a Sears Marine Platinum AGM for my electric trolling motor. For me, the advantages are: 1) easy charging, 2) very slow self discharge, 3) sealed construction.
1) "Easy charging". I have (built, actually) a constant current, constant voltage power supply. I just set the current maximum (short circuit the cables) to 15 amps, and the maximum voltage (open circuit the cables) to the AGM recommended voltage of 14.5v. Then I connect the battery. Next morning, disconnect the battery. Done.
2) "Slow self discharge". If I recall from the specifications, AGM batteries self-discharge is .5% per month. Essentially negligible. I don't need to keep a float charger going over the winter. Toss the battery in a corner and forget it.
3) "Sealed construction". Speaking of tossing batteries...! No filler caps, use the battery on its side if desired. No leaks, no corrosion.
3 years of service powering my trolling motor and no complaints. After an 8 hour day of fishing I typically measure 12.5v so there is plenty of spare capacity.
I think about running two in parallel in my future '21, but then the reality of paying $700 for batteries hits. Ouch.