Lead Acid Battery Balance - Balancer, Equalizer

[markopolo]

It is interesting to me how a few topics can now be linked together because of something we overlooked or maybe assumed was already being used or we might find a new use for etc.

The first topic would be the Norcold resistor removal - http://www.classbforum.com/forums/f5...-mod-3574.html - where we wondered why battery protection settings needed to be adjusted.

The next topic would be Booster's discovery of unequal charging with his new series connected 6 volt AGM batteries - http://www.classbforum.com/forums/f5...ical-3660.html

The next topic would be the E-trek Blog topic where the subject of a Battery Balancer or Equalizer came up - http://www.classbforum.com/forums/f5...blog-3678.html

These topics could all be linked. I mixed Booster's topic in there even though he is not center tapping 12v from a 24v battery bank. Problems can still arise if things aren't matched.

Folks have done the research and have recorded before and after equalizer / balancer installation results.

How about sharing that info here?

[booster]

The two six volts in series that is so very common in RVs is similar to a double 12v to get 24v, although no center tap because nobody needs 6 volts for anything.

I have continued testing on our 4 six volt setup on the bench, to find out what the best way to do the charging is, and as I was doing it, I also was monitoring all the currents and voltages on the entire system.

After a couple of 50% discharges and recharges using return amps to go to float, and done with the matching cable lengths, all the measured stuff (currents and voltages) now matches, with exception of the 6 volts of each battery in a string. They always a hundtreth or two off of each other, but the total voltage of both together matches the other pair perfectly, even if I disconnect the pairs from each other and let them sit. I didn't expect that to be so exact.

It makes me wonder how close the cells within a 12v battery are, if you took a reading across the 3 on each end. I know on wet cells there can be a significant difference in specific gravity, so you would probably see a misbalance of voltage also.

Do you only need a balancer when you are center tapping and getting the batteries way off each other, or could even using one on any series string be a benefit?