Opinion Please on These AGMs for an RV
Somebody Up-Island is selling these type of batteries: http://www.eastpennmanufacturing.com/wp-content/uploads/Unigy-I-IO-Manual-0902.pdf EDIT---What do they mean by saying the Float voltage is ...
Forum Discussion
Hi Phil,
These are a special subset of AGM. It is best to treat them as if they were flooded (following correct charging voltages). The other difference is they do not respond well to super high loads, such as engine starting.
Because the chemistry causes them to need slight higher voltage for charging, I get almost NO recharging while driving. In fact, they tend to discharge. (3 or 4 amps) to the chassis. I did try to solve that by putting an AGM starter battery in place, but it did not solve the issue.
These are a special subset of AGM. It is best to treat them as if they were flooded (following correct charging voltages). The other difference is they do not respond well to super high loads, such as engine starting.
Because the chemistry causes them to need slight higher voltage for charging, I get almost NO recharging while driving. In fact, they tend to discharge. (3 or 4 amps) to the chassis. I did try to solve that by putting an AGM starter battery in place, but it did not solve the issue.
pnichols wrote:
John, as you know ... AGM batteries have lower internal resistance than flooded batteries. One can see this right in their specifications.
This lower resistance means - per basic electrical principals - that they will accept a higher charging current at any applied charging voltage.
That is important for part-time drycampers who want to stay with their stock onboard fixed voltage converters - plus short drives between dry camping spots - for charging of their coach batteries. We elected to stay with our stock converter and go with more-$$ AGM batteries, as opposed to paying more-$$ to retrofit with a multi-stage charger and staying with less-$$ flooded batteries. This combination has worked out well for us over the past 11 years with respect to our camping style.
I guess we could have done both to optimize - spend the $$ to retrofit with a boost voltage charger plus spend the $$ to switch to AGM batteries - but the dollar value would have not been worth it to us to do both of these things.
