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CptSydor's avatar
CptSydor
Explorer
Jun 11, 2018

6V battery won't charge

Took my trailer out of storage for the winter a few weeks ago.

I made a bad decision and left the batteries in over the winter. It was a crazy time just before I put it in storage and it just wasn't a priority.

I have 2 6V batteries, bought about a year ago.

When I got the trailer home, batteries weren't charging from the solar system or when the trailer was plugged in. Took them out, filled them up with distilled water, tried charging them inside as a 12V cell, nothing. Disconnected them, and charged one no problem as a 6V. The other won't charge, voltage is staying low.

Any suggestions of ideas to try? Or is one battery lost?
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    New battery time. Sounds like the bad one has a shorted cell.

    One thing that caught my attention is you had to add distilled. This should have been done LAST YEAR before sroring then charge and EQULIZE if it's done as part of your pre-store. .If done like a month before storage and bouncing down the road just Charge. Then disconnect when you store.
  • From the few replies and my general thoughts, yes, lesson learned, might need a couple new ones.
  • What
    Kind
    Of
    Chargers
    Are
    You
    Using?

    I have had to goose 6 cell batteries with 16.5 volts for a half an hour before they even started to take a charge.

    And in excess of 8.2 volts on a three cell battery.

    If you impress this grade of voltage and the battery starts bubbling very vigorously right off the bat chances are it's gone bad.
  • Odds are it froze and suffered mechanical damage. Discharged batteries freeze pretty easily.
  • Since they are flooded cell with screw caps, I think you can add an electrolytic restorer to each cell. You could also de-sulpher the plates with a special charger they make for that.

    Battery shops do all that for you but it's usually cheaper to do it yourself and much easier to just buy new batteries.

    You want to get them as a pair too.
  • CptSydor wrote:
    Any suggestions of ideas to try? Or is one battery lost?


    Question is - did you disconnect the batteries before storing the trailer? If not, those batteries are pooched ... but you'll want to replace both.

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