AGM vs Flooded Bulk Times
PT keeps asking whether AGMs will spend more time in Bulk at the same charging rate. I found a good example where that can be measured, using ah64id's test with his PD4655 on his pair of Lifeline...
Forum Discussion
My observations on my Northstar AGM-27 battery, indicate that how many amps the battery can accept depends on how many cycles it has gone without a full charge, or without a high amp recharge.
Lots of low and slow recharges until 92% and then if 40 amps are then applied( to a 90Ah battery) amps will start tapering much faster than if the day before had a high amp recharge until 100% was achieved.
I don't really have the data to compare to a flooded battery, not in any scientific manner anyway, but the screwy31 ( 130AH)had no issues accepting 40 amps for quite a while when depleted.
At which point in the SOC that amps started tapering at 14.X volts, compared to the AGM is not data I have on Hand.
And as i do ot ever use a generator, how I recharge is not as important as to someone doing successive 50 to 80%. I Aim for no less than 95% and 100% every 5 cycles.
So how much partial state of charge cycling has been going on, in my opinion, will have huge impacts on when amps begin to taper when held at absorption voltage, and this makes direct comparisions of the AGM vs Flooded in the bulk phase, unwise.
No doubt a test could be set up that would be valid, for that particular AGM brand vs that Flooded brand in X type of use/ charging regimen, but a flat out statement that AGM always charge faster given the same amperage charger as it takes longer to reach absorption voltage, has dozens of qualifiers for it to actually be true anrf repeatable.
But just the fact that when new and healthy an AGM has less resistance, means it will be able to charge faster, if the amperage is there to do so. If the charging source cannot instantly achieve absorption voltage is not there, amps will likely start tapering a bit later on the AGM, and perhaps one could shut off their generator sooner than the guy with flooded jars of the equal state of health and the same number of PSOC cycles accumulated.
Lots of low and slow recharges until 92% and then if 40 amps are then applied( to a 90Ah battery) amps will start tapering much faster than if the day before had a high amp recharge until 100% was achieved.
I don't really have the data to compare to a flooded battery, not in any scientific manner anyway, but the screwy31 ( 130AH)had no issues accepting 40 amps for quite a while when depleted.
At which point in the SOC that amps started tapering at 14.X volts, compared to the AGM is not data I have on Hand.
And as i do ot ever use a generator, how I recharge is not as important as to someone doing successive 50 to 80%. I Aim for no less than 95% and 100% every 5 cycles.
So how much partial state of charge cycling has been going on, in my opinion, will have huge impacts on when amps begin to taper when held at absorption voltage, and this makes direct comparisions of the AGM vs Flooded in the bulk phase, unwise.
No doubt a test could be set up that would be valid, for that particular AGM brand vs that Flooded brand in X type of use/ charging regimen, but a flat out statement that AGM always charge faster given the same amperage charger as it takes longer to reach absorption voltage, has dozens of qualifiers for it to actually be true anrf repeatable.
But just the fact that when new and healthy an AGM has less resistance, means it will be able to charge faster, if the amperage is there to do so. If the charging source cannot instantly achieve absorption voltage is not there, amps will likely start tapering a bit later on the AGM, and perhaps one could shut off their generator sooner than the guy with flooded jars of the equal state of health and the same number of PSOC cycles accumulated.
