Forum Discussion

mrad's avatar
mrad
Explorer II
Jan 14, 2020

Why are my batteries water overflowing during charging?

Yesterday I brought in my two deep cycle batteries from my boat and the one from my camper for winter storage. I check all of the water levels and had ended up adding some distilled water to each, bring it to just under a 1/4" from the top. I had just purchased a new schumacher 15A/3A auto charger. So far all three batteries have overflowed during charging. Did I get a bad charger? What else coull be the cause of this? My old chargers fan went out last summer so it could no longer handle long charges so I had to purchase the new one. I have never experienced this problem before.

Any Ideas?

https://www.amazon.com/Schumacher-SC1280-Charger-Automotive-Batteries/dp/B0797KK3N2/ref=pd_lutyp_crtyp_simh_6_1/138-2305690-8086409?_encoding=UTF8&pd_rd_i=B0797KK3N2&pd_rd_r=8f304cdd-ade6-448a-878d-fc63e6f445da&pd_rd_w=b8jI1&pd_rd_wg=kulF8&pf_rd_p=11bf186d-590b-449a-8161-5414a5d28305&pf_rd_r=084BGV1W7V93NMG7TRAY&psc=1&refRID=084BGV1W7V93NMG7TRAY
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Jan 14, 2020
    I would remove the excess ligquid from each battery placing it in a glass jar for that battery maybe to added back later. Then take the batteries to a good battery shop and have them load tested. Load testing involves first fully charging the batteries before doing the load test. Be aware that the battery acid is already diluted some because of the overfill and overflow, hence the liquid is no longer nominal.

    If the batteries are OK it might be worthwhile adding some acid back to achieve the correct liquid balance. Perhaps check with the battery shop first and get their input on the overfill. BTW A auto parts store is NOT a good battery shop.

    After the load test if they pass then they need to be recharged.
  • time2roll's avatar
    time2roll
    Nomad
    Jan 14, 2020
    mrad wrote:
    philh wrote:
    you over filled them. To the bottom of the ring with full charge


    By the ring, do you mean fill them to the bottom of the cylinder the caps snap on?
    You should fill them to 1/4" below the split ring that extends down into the cell. Just touching the bottom is absolute max.

    Actually the electrolyte will expand as the battery is brought from low charge to full charge. Best to just verify the plates are covered and top off (as above) after the battery is fully charged.

    OK there is a possibility the battery is shorted and excessive bubbling has forced the electrolyte out through the cap.
  • 3_tons's avatar
    3_tons
    Explorer III
    Jan 14, 2020
    All I can add is that I had to toss two near new smaller Schumacher maintainer chargers because they ruined two of my AGM batteries...
  • azdryheat's avatar
    azdryheat
    Explorer
    Jan 14, 2020
    philh wrote:
    you over filled them. To the bottom of the ring with full charge
    x2
  • mrad's avatar
    mrad
    Explorer II
    Jan 14, 2020
    philh wrote:
    you over filled them. To the bottom of the ring with full charge


    By the ring, do you mean fill them to the bottom of the cylinder the caps snap on?
  • wolfe10's avatar
    wolfe10
    Explorer
    Jan 14, 2020
    At this point all we can do is SPECULATE.

    What is charging voltage after a couple of hours (i.e. float voltage)?
  • philh's avatar
    philh
    Explorer II
    Jan 14, 2020
    you over filled them. To the bottom of the ring with full charge

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