It’s been three years of utilization of the 48V 220 ah battery bank for Alice Gale. We have only had the opportunity to motor sail about a dozen times in that period and two of the eight 6v batteries have failed. Part of an ongoing problem with the AGM 6V solution running in series to make the 48V power is having a good charging system. My installation included two twin 12V Genius chargers. These have worked flawlessly on other 12V batteries I own in keeping a 24/7 charge while maintaining maximum battery life. Unfortunately I have found that the Genius charger simply can’t charge two high capacity 6V batteries in series. I have only been able to plug the 12v charger in for a 48 to 72 hour period before a ‘failsafe’ shut off occurs to ‘prevent’ battery damage. This hasn’t worked well as I then allowed the batteries to self discharge to a low damaging state from disuse.
To correct this battery issue I have substituted the eight 6V 220Ah AGM batteries for four 100ah wet cell 12v batteries. These will be maintained in good condition by the Genius charger. (I will have to inspect water levels of the batteries periodically. I will likely give you an update a year or two from now on how successful this turns out.) While I have cut my running time in half, the 100ah capacity give me about 4 hours of operating time at my current cruising speed before battery depletion falls below 50%. This is more then adequate for my intended usage and I can comfortable replace batteries every few years at a reasonable cost. If I was to redesign the system from scratch I may be tempted to update to a LiPo2 system with a correspondingly correct charger and monitoring system, but my usage of Alice Gale is so limited that I believe this would be a money sink hole and wouldn’t add value.
Changing out the batteries have also lowered my gross boat weight by 250 lbs so it again is floating a bit higher in the water and has lost a tad of that desired stability I enjoyed with the heavy battery bank. I might be adding a water ballast system in the future.
Alice Gale had a fair amount of surface checking on the paint so I blocked her off the trailer. I then spend a week of sanding and finally spraying several new top coats of paint. Good as new!