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Gel Batteries

September 21, 2011, 05:50:13 pm

I just had to replace my Sonnenschein GF 12 160 V Gel batteries they both went dead and would not take a charge. They were put in at FOT november of 2008.  One cap on each battery was loose and came out when I washed the batteries off before we did the replacement.  A WORD OF CAUTION, the Germany Sonnenschein batteries have the + and - post on the opposited side of the battery from what the standard is.  So be careful are you may fry something.  When I got to the battery store, I had antifreeze leaking at the rear where the crossover pipe from radiator on the right side goes over to the left of the engine, there is a short piece of radiator hose to connect the 2 pipes together it is about 8 inches long, just above it is a 1 inch oil line that rubbed a pin hole in the radiator hose.  You might want to check your system and see if you might have the same happen to you.  Attached is photo.

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Re: Gel Batteries

Reply #1 – September 21, 2011, 05:59:28 pm

Jimmy, I am little confused. I didn't think Gel batteries had caps. From the photo, it sure looks like my old 8D Lead Acid batteries. Why do the German Gel batteries have caps.

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Re: Gel Batteries

Reply #2 – September 21, 2011, 06:14:25 pm

Jimmy, I hate to ask, But, it appears the label on the battery in the picture says Jun 68, It is not real clear, but from the picture two things are appearant, 1 the batteries look very old, not 2008, models  2, that label does look like Jun 68, not Jun 08.  I am sure that is just my eye balls and not really Jun 68 ?

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Re: Gel Batteries

Reply #3 – September 21, 2011, 07:11:07 pm

Jimmy, What in the world was FOT thinking installing GERMAN batteries with REVERSED Posts ? Looks like a disaster in the making.
Gary B

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Re: Gel Batteries

Reply #4 – September 21, 2011, 07:56:37 pm

Gary, I don't know why they did that, and no one told me when they installed them about it.  That's why I posted this, might save someone a problem.

Dave, the date was Jun 08.  I talked to James T. he said they quite selling that battery.

Kent, I don't know why, the other caps wont come out the cap part is loose and free wheels but won't screw out. I don't know why the to were out.

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Re: Gel Batteries

Reply #5 – September 22, 2011, 06:17:35 am

My Deka 8D gels have caps - every make of gel I looked at has them. I believe they are there for venting if the cell overpressurizes.

The trashed 8D wet cell that came with the coach that I pulled out of the battery bay looks like Jimmy's. There are two cells that appear to be shorted. The wet areas around the caps - that's the giveaway. The two shorted cells in my battery continued to seep water out the caps for several months after I took the battery out.

Might be worth checking the charging systems (alternator and convertor/inverter) to make sure you aren't overcharging.

Steve

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Re: Gel Batteries

Reply #6 – September 22, 2011, 01:59:02 pm

DO NOT remove the caps from a Gel, an AGM, or any sealed battery because that would let in air and other contamination, which will damage the battery.

The caps on Gel and AGM batteries which I have will spin but are not threaded so must be pryed out.

All sealed batteries have pressure relief valves so when rapid charge or discharge causes gas pressure to build up the battery does not explode. The Oxygen and Hydrogen gas produced during charging or discharging is recombined back to water inside the battery unless gas is produced too rapidly like during equalization.

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