I realize the title reads like an oxymoron: how can a 1 amp trickle charger equalize batteries? But I did an experiment and I think it works.
I had two Group 24 "dual purpose" batteries on a trickle charger hooked up in parallel for the last 6 months while we were in Connecticut. Before reinstalling them in my boat here in Florida I topped up the water level. A couple of cells used about twice as much water as the others, maybe they were low to start with 6 mo ago.
So I checked the SG with a hygrometer and sure enough those two cells were about 0.05 points lower than the others. Not surprising, the water diluted the electrolyte. So I fooled the charger into restarting its charging phase (I call it that because it is two steps) at about 13.8 volts by disconnecting it for a moment. It put out 0.8 amps to start with. It slowly dropped to 0.5 amps and then switched to float at 13.1 volts after about 18 hours. Then I did it again. Same thing but it started at 0.7 amps and took about 12 hours.
When I checked the SG on the low cells they were back up to 1.275 the same as all of the others. They had been "equalized".
I didn't think that small current could do the job, but the numbers said it did.
David
I had two Group 24 "dual purpose" batteries on a trickle charger hooked up in parallel for the last 6 months while we were in Connecticut. Before reinstalling them in my boat here in Florida I topped up the water level. A couple of cells used about twice as much water as the others, maybe they were low to start with 6 mo ago.
So I checked the SG with a hygrometer and sure enough those two cells were about 0.05 points lower than the others. Not surprising, the water diluted the electrolyte. So I fooled the charger into restarting its charging phase (I call it that because it is two steps) at about 13.8 volts by disconnecting it for a moment. It put out 0.8 amps to start with. It slowly dropped to 0.5 amps and then switched to float at 13.1 volts after about 18 hours. Then I did it again. Same thing but it started at 0.7 amps and took about 12 hours.
When I checked the SG on the low cells they were back up to 1.275 the same as all of the others. They had been "equalized".
I didn't think that small current could do the job, but the numbers said it did.
David
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