Need some battery advice!
I'm currently having had an issue with my Interstate 12V (dual) batteries in my Arctic Fox camper, in that after 3 days of boon docking, my fridge stopped working, thus realizing I must be below 6 vol...
Forum Discussion
" The problem with paralleling different capacity batteries is that the discharge curve isn't linear. Once you draw a certain amount of power, the smaller of the batteries can become a load on the larger. It will work, but you don't get the capacity increase you might think you are getting. Your actual capacity will be close to two of the small batteries in parallel rather than the sum of the two"
The larger accumulator will augment the voltage of the smaller if the chemistry and construction are twins. Do an amp hour test to verify this. The results of which will be indisputable. The science can be compared to adding a smaller shock absorber in tandem with a larger unit.
Different chemistries are another animal. A shorted cell is the antagonist in a paralleled configuration. Thus 9 batteries with open cells can be paralleled with a remaining "good" battery with no ill-effect on the good battery. But the nine must not have a quiescent self discharge rate higher than the good battery.
This is not an esoteric subject. Identification of a shorted cell can be done with incidental specific gravity measurement or time-elapse voltage degradation of isolated batteries (meaning out of circuit).
The larger accumulator will augment the voltage of the smaller if the chemistry and construction are twins. Do an amp hour test to verify this. The results of which will be indisputable. The science can be compared to adding a smaller shock absorber in tandem with a larger unit.
Different chemistries are another animal. A shorted cell is the antagonist in a paralleled configuration. Thus 9 batteries with open cells can be paralleled with a remaining "good" battery with no ill-effect on the good battery. But the nine must not have a quiescent self discharge rate higher than the good battery.
This is not an esoteric subject. Identification of a shorted cell can be done with incidental specific gravity measurement or time-elapse voltage degradation of isolated batteries (meaning out of circuit).
