Amps Rising not tapering During Abs Charging?
Charging with the pm4b last evening, I brought the bank to 9.2a @ 14.64Vabs. Amps plateaued there early on during the 2 1/2 hour charge. It was getting late, so I shut things down for the night. To...
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MN,
Until this morning, nothing was hooked up, except for the inverter (which remains off) and the Trimetric (also off). And the Trimetric was not hooked back up until recently. This morning, I hooked up the fridge to 12v, and have it cooling down on 120Vac, while I do yet another full charge in preparation for tomorrow's capacity test. I forgot to check OCV before turning the fridge on, but voltage dropped to 12.59 with only the 0.9a fridge draw. Thus the reason for the capacity test.
These batts use to hold strong at 12.78v, for weeks at a time. I noticed a drop in resting ocv last fall, after doing several deep cycles. Before that, I never let the bank go below 12.5v, and usually only to ~ 12.6v.
Last season they suffered some over-charging/excessive gassing, as my Peak 40a seems to have lost it's ability to hold voltage down to less than 15v. That was why I switched to using the pm4b-45. I did a bunch of charge cycles, in order to familiarize myself with the whole process. The guys here were very helpful in guiding me through the ins and outs of charging with a converter. As a result, I modified the pm4b, so I can set Vabs at my own setting, rather than its factory preset 13.6Vabs. It was after this series of charges, including some top charging and a rather successful EQ on two of the four 6's, that I noticed resting ocv's were starting to drop. And then we had a brutally cold winter, which may or may not have had an adverse effect on the bank? I kept things topped up throughout the winter, with the occasional top charge.
As you can see, SG readings are good, and resting voltages are even across the bank. But there is definitely a huge increase in discharge, at rest. Whether that is self-discharge, or a slow drain, I'm still not entirely sure. But I'm leaning heavily toward self-discharge, as I've seen a drop in ocv even with absolutely everything (physically) disconnected from the bank.
Hopefully this capacity test, and the 50% soc readings, will point me to what's happening. But if all cells share the constant 10hr load evenly, I would think that would be an indication there are no individual bad cells, per sae, but general plate damage throughout?
Until this morning, nothing was hooked up, except for the inverter (which remains off) and the Trimetric (also off). And the Trimetric was not hooked back up until recently. This morning, I hooked up the fridge to 12v, and have it cooling down on 120Vac, while I do yet another full charge in preparation for tomorrow's capacity test. I forgot to check OCV before turning the fridge on, but voltage dropped to 12.59 with only the 0.9a fridge draw. Thus the reason for the capacity test.
These batts use to hold strong at 12.78v, for weeks at a time. I noticed a drop in resting ocv last fall, after doing several deep cycles. Before that, I never let the bank go below 12.5v, and usually only to ~ 12.6v.
Last season they suffered some over-charging/excessive gassing, as my Peak 40a seems to have lost it's ability to hold voltage down to less than 15v. That was why I switched to using the pm4b-45. I did a bunch of charge cycles, in order to familiarize myself with the whole process. The guys here were very helpful in guiding me through the ins and outs of charging with a converter. As a result, I modified the pm4b, so I can set Vabs at my own setting, rather than its factory preset 13.6Vabs. It was after this series of charges, including some top charging and a rather successful EQ on two of the four 6's, that I noticed resting ocv's were starting to drop. And then we had a brutally cold winter, which may or may not have had an adverse effect on the bank? I kept things topped up throughout the winter, with the occasional top charge.
As you can see, SG readings are good, and resting voltages are even across the bank. But there is definitely a huge increase in discharge, at rest. Whether that is self-discharge, or a slow drain, I'm still not entirely sure. But I'm leaning heavily toward self-discharge, as I've seen a drop in ocv even with absolutely everything (physically) disconnected from the bank.
Hopefully this capacity test, and the 50% soc readings, will point me to what's happening. But if all cells share the constant 10hr load evenly, I would think that would be an indication there are no individual bad cells, per sae, but general plate damage throughout?
