Battery Question, Again
Folks I come to you, hat in hand again to try to help me understand what is going on with my batteries. I have four 6 volt batteries in my camper. I bought new batteries in September last year. I brou...
Forum Discussion
MEXICOWANDERER wrote:
USUALLY 12 cells with a uniform 1.260 gravity are not badly sulfated
I would perform a current limited TOP CHARGE on these batteries.
With current limiting here is some help.
Stage one. Four hours at 14.4 volts after which are all 12 cells bubbling slightly? Good. Disconnect. Let set for 2 hours then recheck gravity.
Some cells not bubbling?
Increase voltage to 14.8 and repeat top charge but only for 2 hours
Are the reluctant cells now bubbling? Same drill. rest 2 hours than recheck gravity.
You have a weak sister cell? One that resisted 14.8 volts? It will need to be amperage limited to 11-amps at an 8-volt top limit. Full equalization then you need to keep an eye on it. Starting at 1.260 gravity this would be quite unusual.
There WILL BE one or two cells that will be slightly more reluctant to recover to 1.275. You can find these by checking all cells right after shutting off the charger. Mark them, these are your go-to cells when you believe a hydrometer test is in order down the road. No sense in stabbing 12 cells when there are just one or two delinquents. Put the batteries with the weak sister cells in the most accessible location for dipping.
Remember the chemistry change continues after the charging current is removed. I've found two hours to be a rational wait.
OK, did this. Voltage reading after 2 hours 12.71, SG on all cells at least 12.75 with a couple at 12.80. Am I good now or do I still need to do an equalizing charge?
