Battery: AGM vs. Flooded Cell
Our 5er, 2016 Continental Coach, currently has 4 6v Interstate “Maximum” Deep Cycle Batteries. I am planning to replace them, and am considering the GC2 Trojan T-105 w T-2 Technology (flooded cell), a...
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You can't charge any faster than your charger's max amps.
There is a slight time saving once you get to the Absorption Stage where the AGM has a little more acceptance rate per SOC, but Bulk Stage timing is about the same.
Some figures from past examples on this topic, noting the %SOC when Bulk ends using various charging rates. (The lower the charging rate, the higher the %SOC when Bulk ends after a time at constant max charger amps)
Wets- 32% and 65%SOC
AGM- 40% and 63%SOC
Wets-19% and 72.5%SOC
AGM- 15% and 75% SOC
So if you are off-grid doing 50-80s you are going to shut off the gen not long after Absorption starts anyway, and you will not realize much of any theoretical time saving by having AGMs.
Solar usually has a very low charging rate, so a high SOC when amps start to taper. This is true with Wets and AGMs. Hard to say if you are any more likely to get to 100% before dark with either type.
Li batts do shine in this regard. At 100% charging rate, they reach 65% SOC when Bulk ends, and at a less stressful (and recommended rate with Battle Borns) 50% charging rate, Bulk ends nearer 80% SOC. Solar with Li means you won't see much of that faster charge with them either due to the low charging rate, unless you have a very large solar array.
We were looking at all this a while back when discussing the wild claim seen in advertising, that AGMs charged "five times faster" :)
There is a slight time saving once you get to the Absorption Stage where the AGM has a little more acceptance rate per SOC, but Bulk Stage timing is about the same.
Some figures from past examples on this topic, noting the %SOC when Bulk ends using various charging rates. (The lower the charging rate, the higher the %SOC when Bulk ends after a time at constant max charger amps)
Wets- 32% and 65%SOC
AGM- 40% and 63%SOC
Wets-19% and 72.5%SOC
AGM- 15% and 75% SOC
So if you are off-grid doing 50-80s you are going to shut off the gen not long after Absorption starts anyway, and you will not realize much of any theoretical time saving by having AGMs.
Solar usually has a very low charging rate, so a high SOC when amps start to taper. This is true with Wets and AGMs. Hard to say if you are any more likely to get to 100% before dark with either type.
Li batts do shine in this regard. At 100% charging rate, they reach 65% SOC when Bulk ends, and at a less stressful (and recommended rate with Battle Borns) 50% charging rate, Bulk ends nearer 80% SOC. Solar with Li means you won't see much of that faster charge with them either due to the low charging rate, unless you have a very large solar array.
We were looking at all this a while back when discussing the wild claim seen in advertising, that AGMs charged "five times faster" :)
