David, I believe the key to AGM longevity is to keep them on a proper charger 24/7. This is what I have done with excellent results.
Jack W4GRJ On Nov 30, 2013, at 9:36, "David Cutter" <[email protected]> wrote: Hello Jack I can see your experience is good. I haven't so far uncovered what is meant by "life" for these batteries, perhaps it's when the energy being fed in is more than double what is taken out or something of the kind, or the time it takes to drain to a projected cut-off. I doubt that the internal resistance is measured. As an ex marine operator, standby (emergency) battery life was very important and they were replaced on a strict schedule, however good or bad they might be in use - a bit like alarm batteries and such like. I know amateur requirements are somewhat "flexible" shall we say : - ) David G3UNA I live in Florida and as a fishing guide, the 4 group 27 AGM batteries on my boat have performed perfectly now for over 4 years of almost daily use. I have almost every piece of marine electronics and radios running on the boat. Jack W4GRJ On Nov 30, 2013, at 3:17, "David Cutter" <[email protected]> wrote: As I understand it, AGM batteries are designed for high current performance, ie good for engine starting, but for radio use I would have thought that gel batteries would be more suitable as they have a longer life, particularly in hot climates. I have no experience of either, just reading the specs. David G3UNA > On Thu, 28 Nov 2013 05:36:15 +1000, John's email <[email protected]> wrote: > > I use 2 x 6V 300AH AGM batteries as the prime power source in my shack. > I use a 15Amp smart charger to keep them topped up whilst mains power is > available and a 200Watt solar panel is available for after cyclones > (hurricanes) as we invariably lose power for a day or three after them. > > > -- > Jeff Cochrane - VK4XA ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html

