Does anybody know if a fully charged gell battery has a slightly lower voltage than a conventional wet , lead/acid battery?
I have an Optima sitting here that will pass a load test , charge up fine , but if it sits for a week levels off at 11.51 volts Yet I can still toast bread on my load tester.

I have a pair of Optima 34M's in my boat, and they seem to drop off to about 12.1V after sitting a while. They seem to start the 540 just fine. 11.5V might be a bit low...

The 11.51v does seem a bit low. How old are they? I ran Optimas in 2000 and 2001 and switched to regular starting batteries that I swap out every two seasons. I suspect the Optimas are better today and most of the boat chargers have charge rates compatible with both types of batteries. I'm on my third Charles charger. The first one was calibrated for conventional batteries, the last two were calibrated for either.Between the cars and the boat that sit for extended periods of time, I usually see 12.1 to 12.3v. Optima has a descent web site and a Hot Line. It would be interesting to hear what they have to say.

The battery is approaching a year and a half old. I'll check the Optima site if I can find it...Thanks

Try optimabatteries.com. Toll free number for their Colorado office is 888-867-8462. Just tryin to help. Lou