AGM Adventures- Update
Updated 31 Jan 17 Initial results. I will re-test the AGM after it does one deep cycle to confirm these results. EDIT completed 6 Oct Test was to put the test battery as the only battery run...
Forum Discussion
Having an AGM that is nothing like what you guys are buying, a surplus Telecom, very thick, very few plates that's about 150ah and weighs a whopping 105 pounds and is designed to last 10 years, the DEKA I run has some different requirements in recharging.
4 or 5 days of 150w 8.5 amps solar panel in a row does not give it what it needs to get things stirred up and fully recharged. On the 5th or 6th day, it sees the Megawatt, set at 14.4V, first thing in the morning, for a couple of hours on the generator. The battery will take a maximum of 20 to 21 amps at 14.4V. It will be slow in dropping the amps down at this voltage, at least an hour. You can't rush recharging it. The battery temp increase is minimal, as in hardly noticeable, when shot with an IR temp gun, maybe 4 or 5 F temp rise.
I absolutely love having that RC battery charger meter in line with my MegaWatt, to tell me exactly what is going on, V wise and Ah wise. It takes all the guess work out of what the state of charge is with the battery.
2 or 3 hours on the MegaWatt at 20-21 amps restores the battery. End of trip, it sits on the MegaWatt at home until I see a .75ah draw at 14.4V, then I shut the MegaWatt off, and let it sit, fully top charged. 72 hours after a full recharge, the battery, at around 80F, will show 12.88V
The battery chemistry will take what ever amps you can give it, and self limit itself. Watch the heat, don't let it get too hot, and then watch the amp take rate as it finishes recharging. If your battery has it's temperature rising, you need to back off on the voltage a bit, so it doesn't make heat.
It's not rocket science here, just take notes on a new battery and what it does, what it's results are, and file them away for reference. I can't and don't run heavy inverter loads on my telecom battery. It wasn't designed for it. It was designed for low and slow amps drawn over long periods of time. It works fine for me, in my 21 ft travel trailer, as a single battery. No toaster or microwave or electric coffee for me, unless it's on the Eu2000i generator.
My rig is small, my needs are small, but everything is scaleable, to a certain extent. 40 or 50 amp hours pulled in 24 hours is a huge power hog day for me, I am usually closer to 25-40. I've had the battery a year now, still doing great. Mex tells me 9+ years to go on it.
4 or 5 days of 150w 8.5 amps solar panel in a row does not give it what it needs to get things stirred up and fully recharged. On the 5th or 6th day, it sees the Megawatt, set at 14.4V, first thing in the morning, for a couple of hours on the generator. The battery will take a maximum of 20 to 21 amps at 14.4V. It will be slow in dropping the amps down at this voltage, at least an hour. You can't rush recharging it. The battery temp increase is minimal, as in hardly noticeable, when shot with an IR temp gun, maybe 4 or 5 F temp rise.
I absolutely love having that RC battery charger meter in line with my MegaWatt, to tell me exactly what is going on, V wise and Ah wise. It takes all the guess work out of what the state of charge is with the battery.
2 or 3 hours on the MegaWatt at 20-21 amps restores the battery. End of trip, it sits on the MegaWatt at home until I see a .75ah draw at 14.4V, then I shut the MegaWatt off, and let it sit, fully top charged. 72 hours after a full recharge, the battery, at around 80F, will show 12.88V
The battery chemistry will take what ever amps you can give it, and self limit itself. Watch the heat, don't let it get too hot, and then watch the amp take rate as it finishes recharging. If your battery has it's temperature rising, you need to back off on the voltage a bit, so it doesn't make heat.
It's not rocket science here, just take notes on a new battery and what it does, what it's results are, and file them away for reference. I can't and don't run heavy inverter loads on my telecom battery. It wasn't designed for it. It was designed for low and slow amps drawn over long periods of time. It works fine for me, in my 21 ft travel trailer, as a single battery. No toaster or microwave or electric coffee for me, unless it's on the Eu2000i generator.
My rig is small, my needs are small, but everything is scaleable, to a certain extent. 40 or 50 amp hours pulled in 24 hours is a huge power hog day for me, I am usually closer to 25-40. I've had the battery a year now, still doing great. Mex tells me 9+ years to go on it.
