If I plug my trailer in for 2-3 days I start to smell vapors from the batteries overcharging. Is the battery charger supposed to quit when the batteries are fully charged. If so is there any fix to this problem? Thanks
Posted 2006-01-23 4:59 PM (#35886 - in reply to #35883) Subject: RE: batteries over-charging
Expert
Posts: 2689
Originally written by ND COWBOY on 2006-01-23 3:59 PM
If I plug my trailer in for 2-3 days I start to smell vapors from the batteries overcharging. Is the battery charger supposed to quit when the batteries are fully charged. If so is there any fix to this problem? Thanks
Depends on the particular battery charger.
Battery "conditioners" typically are claimed to not overcharge.
You could do the arithmetic;
If you (continue to) pump 10 amps into a battery that has an ampere hour capacity of, say 125 AH, it will be overcharging at 1/2 day - well short of your quoted 2-3 days.
Warning: This isn't linear, a very flat battery will take very little charge for the first few hours, then more as it's internal resistance goes down, then less as it's terminal voltage goes up.
The only accurate way to check the state of charge is to check the acid's specific gravity. It rises with increasing charge, but I don't remember the optimum value.
Posted 2006-01-23 9:57 PM (#35894 - in reply to #35883) Subject: RE: batteries over-charging
Veteran
Posts: 216
Location: Chillicothe, Ohio
The inexpensive standard type dc converters that are usually installed dont do a good job of charging 12dc batteries. Usually they end up cooking off the water like you noticed. The higher quality chargers have a 3 step charging system.