Should I replace my cart batteries?
bc buck
Registered Users Posts: 59 ✭✭
I posted this in June-
While doing maintenance I noticed positive terminal side of all 4 of my wet 6 volt cart batteries slightly bulged. They where put on line January 2017 and not abused. Only get about 50 50% discharges a year. Did get down to -15f once this winter but should have been fully charged. Also batteries seem to still hold close to new on the AH.
Now with full charge was not able to run microwave and thought something was up. Tested all 4 batteries with hydrometer and found one center cell not reading. All other cells test like new. Is it safe to run this bank or should I replace all 4 cart batteries. Was hoping to get another year out of these to give me time for research into lithium upgrade.
While doing maintenance I noticed positive terminal side of all 4 of my wet 6 volt cart batteries slightly bulged. They where put on line January 2017 and not abused. Only get about 50 50% discharges a year. Did get down to -15f once this winter but should have been fully charged. Also batteries seem to still hold close to new on the AH.
Now with full charge was not able to run microwave and thought something was up. Tested all 4 batteries with hydrometer and found one center cell not reading. All other cells test like new. Is it safe to run this bank or should I replace all 4 cart batteries. Was hoping to get another year out of these to give me time for research into lithium upgrade.
Comments
The battery with the cell near 1.00 SG, it is not doing you any good (the "Dead" cell is not supplying voltage to that string--And depending if it is "open or shorted", may also be under/over charging the rest of the cells/batteries in the string). If these, were for example "cheap" Golf cart batteries, you may want to replace the one with the dead cell for $100 +/- and if this lasts 1-2 years--And you are happy--Then why not (it is always possible for another cell/battery to fail down the road--No guarantees here).
3-5 years is good for Golf Cart/Lower cost Lead Acid batteries... In cold regions you may get as much as 7+ years.
The positive terminal "bulge" is common as FLA and AGM batteries age. Don't think the -15F hurt anything.
May also be time to review charging for bank. Do you get 10% rate of charge? Or at least >=5%? Do you get the batteries "on charge" after discharging (don't set at less than 75% State of Charge before recharging)?
-Bill
If the bad battery is low voltage, it can be sinking current during charging--Over charging its mate (over heating, using too much water, gassing too much, etc.), and possibly limiting charging to the other parallel "good strings". And will not supply much "useful" current until the battery bank is near 10 volts (i.e., other batteries are "dead").
In any case--disconnecting that battery/string is probably the best bet.
In general, the rule of thumb for battery aging (not talking about cycling life here) is: For every 10C over 25C (18F over 77F), the batteries age 2x faster... 80F bank is not that hot (vs 77F standard temperatures). Conversely, for every 10C under 25C, the batteries have 1/2 as fast. This accelerated aging only occurs when the batteries are "hot" (i.e., 95F for 3 months of summer, they have "lived/aged" 6 months).
-Bill
you mite get a year or so out of it.
Sams club sells a lot of battery’s and people are returning there old battery’s for the 5 dollar core charge .
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
Some times the core charge is 20 but I’ve payed 5 $ and I’ve bought a bunch with no core charge ?
so you can get a good battery at Approximately the same age and same condition as what you have allready .
My battery’s go to a recycler when they are paying top dollar $$$$ I get 45 bucks some times for a big battery
2.1 Kw Suntech 175 mono, Classic 200, Trace SW 4024 ( 15 years old but brand new out of sealed factory box Jan. 2015), Bogart Tri-metric, 460 Ah. 24 volt LiFePo4 battery bank. Plenty of Baja Sea of Cortez sunshine.