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laknox's avatar
laknox
Nomad
Aug 13, 2013

Battery question

Last year I replaced my 2 12v batteries with 2 6v golf cart batteries from Sam's Club. They've been great and given me a big boost in capacity. This last trip, though, I noticed that, even after being plugged in for 3 days after topping them off with distilled water, I was only getting 3/4 lights on my indicator. When plugged in I got 4/4 lights, so I know that the top bulb =is= working. Now, they were down a bit, but the plates looked to have 1/4 to 3/8 an inch over them. I put in a good half-gallon between the 2 batteries. Even after driving for 3 hours to our camp site, I never had more than 3 lights. I never went =below= 3 lights during the 4 days we were there and had 45w of solar on them as much as possible. Does it take that long to get them back up to snuff or could I be starting to see issues with my power converter?

Lyle

15 Replies

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  • AZ_T_T's avatar
    AZ_T_T
    Explorer
    Aug 13, 2013
    Are you only using the converter in your FW or do you always keep them hooked up to a 3 way battery charger like a Battery Tender?

    When I switched to 6v golf cart batteries the guys at Interstate Batteries said it was a good idea to always keep them hooked up to a 3 way float charger. I always have and they have worked great, one nice side benefit is I almost never have to add water.

    One other thing: I've noticed it doesn't take much to get my gauge to drop from 4/4 to 3/4, but it will stay at 3/4 for a whole weekend of boondocking. Maybe it's just the gauges?
  • elivi8's avatar
    elivi8
    Explorer
    Aug 13, 2013
    For 6 volts to work properly they need 20-30 full discharge cycles. For most campers this can be years or more! The plates are thicker and need to be worked in. This information has been taken from other posts. Do some research as I have. I wonder if going to 6 volts is even worth it based on the information.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Aug 13, 2013
    Hi,

    Have you equalized them?

    Check the specific gravity on all the cells. One may be "weak".
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Aug 13, 2013
    Forget about that 'state of charge' monitor.
    It will always show 4/4 when you have AC power

    Really want to know battery state of charge.......check voltage with a meter and/or specific gravity of each cell

    Quick article on Testing battery.......LINK
  • korbe's avatar
    korbe
    Explorer
    Aug 13, 2013
    A couple things come to mind. First, no matter how charged my batteries are, if I check the capacity board while there is a load on the batteries, they will not read accurately - they show low voltage. Secondly, it seems to me that a half gallon of distilled water is an awful lot for topping off the batteries. Was the water level below the plates? Or did you fill them to the caps?

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