First time charging new batteries
I just bought a pair of Costco/Interstate 6 volt batteries. On the first two charges, they don't seem to be accepting charge as fast as I expected. They have not gone above 31 amps either time. I a...
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The charging voltage is fine for 40F. However, as the batts warm up, it would be slightly high, perhaps, but still not too high for a "top" charge. Come the warmer weather, I would keep it down around 14.6 to 14.8, and then drop it to 14.4-14.6 in the hot weather. I find my 6's do well at lower voltages than some 12's do; according to what's been shared here. Keep an eye on how much they're gassing... small bubbles every couple of seconds or so.
Re; 1st charge:
At 12.44v (2 x 6.22v), they were likely around 70% soc, so they should have accepted the full charge rate. But how long did they sit discharged??? You may need to return them if they're badly sulfated.
What do you mean by "they wandered between 8 and 12 amps"? Did the current go up and down?
Re; 2nd charge:
They clearly did better the second time round, but at 12.3v, that's likely less than 60% soc, and again, they should have accepted the full charge rate.
??? Did you let the batteries sit for at least 15 minutes, with no load, before taking the RESTING/ocv reading? Perhaps they had not rebounded yet, and you were seeing a lower voltage due the peukert effect. In this case, they may have been high enough in soc to start tapering immediately.
Did you confirm the voltage reading with another meter?
Other than not starting at the full 40 amps, the 2nd charge profile looks fine.
You need to confirm soc with S.G. readings.
Re; 1st charge:
At 12.44v (2 x 6.22v), they were likely around 70% soc, so they should have accepted the full charge rate. But how long did they sit discharged??? You may need to return them if they're badly sulfated.
What do you mean by "they wandered between 8 and 12 amps"? Did the current go up and down?
Re; 2nd charge:
They clearly did better the second time round, but at 12.3v, that's likely less than 60% soc, and again, they should have accepted the full charge rate.
??? Did you let the batteries sit for at least 15 minutes, with no load, before taking the RESTING/ocv reading? Perhaps they had not rebounded yet, and you were seeing a lower voltage due the peukert effect. In this case, they may have been high enough in soc to start tapering immediately.
Did you confirm the voltage reading with another meter?
Other than not starting at the full 40 amps, the 2nd charge profile looks fine.
You need to confirm soc with S.G. readings.
