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owenssailor's avatar
owenssailor
Explorer
Mar 02, 2017

Battery issues

Our trailer has 2 group 24 12V batteries. They seem to discharge quickly. With just the parasitic loads of fridge electronics, CO/Propane monitor and radio(not running) the voltage will drop from 12.6 to 12.4 over 6 hours.

I measured the draw and it was 0.6A

I think this means the batteries are done.

I am considering either Trojan or US Batteries for replacements. Does anyone have experience with these brands?

I cannot fit batteries larger than group 24 12V into the battery area on this trailer.

Thanks

17 Replies

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  • SoundGuy's avatar
    SoundGuy
    Explorer
    Mar 03, 2017
    owenssailor wrote:
    I am considering either Trojan or US Batteries for replacements. Does anyone have experience with these brands?


    When selecting any battery it's most important to match them to the characteristics of the charger you intend to use to maintain them. T-105s are a good GC-2 choice BUT Trojan specifies a 14.8 volt bulk charge ... your charger capable of that? :h

    That said, before ditching your current batts have you verified their actual condition, have you tried to equalize them, checked fluid level? :h
  • 2112's avatar
    2112
    Explorer II
    Mar 03, 2017
    Have you equalized your batteries? Performed any real maintenance?
    Measure their SG, properly water and properly equalize them before you give up on them.
  • dougrainer's avatar
    dougrainer
    Nomad
    Mar 03, 2017
    Look at this chart. 75 percent capacity after 6 hours, would indicate marginal batteries, not bad batteries. IF they are over 2 years old, then I would replace. Doug

    DEEP CYCLE BATTERY VOLTAGE & STATE OF CHARGE
    State of Charge

    Sealed or Flooded Lead Acid
    percent of charge

    100 12.75
    75 12.40
    50 12.20
    25 12.00
  • landyacht318's avatar
    landyacht318
    Explorer
    Mar 02, 2017
    The absolute best group 24 marine battery is barely any better than wally world specials.

    IF you have the height available, trojan t-105s have the same footprint as group 24.

    There are no true deep cycle group24.

    Limiting yourself to 12v group 24's, and you want quality, then Lifeline or Full river AGM.

    There are no true deep cycle flooded group 24.
  • owenssailor's avatar
    owenssailor
    Explorer
    Mar 02, 2017
    Voltage was measured after 1 hour after charging finished and then repeated for 6 hours. Draw from parasitic loads was 0.6A. I am looking for 12V batteries
  • westend's avatar
    westend
    Explorer
    Mar 02, 2017
    Without measurements of amperage drawn and specific gravity, a statement of whether voltage was measured after recovery or while in use, all would be a guess as to the health of the batteries.

    Trojan has been building the industry standard 6V battery for quite a few years.

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