I don’t often ask, but when I do……

[drycamper]

I reach out to the experts, here. I have two 6 V Costco golf cart batteries, in series. I’ve never been fully satisfied with how long they will last while Boondocking. Am I getting a full charge through the trailer converter, or a smart charger (12volt)? I have never gotten real good specific gravity readings from them. Do you think I just got two bad batteries or perhaps my chargers aren’t giving them what they need. I tried the recondition mode on my CTEC, and it would never cycle past float mode, into the recondition mode.

Thanks

[chuckster57]

How old are they? Specific gravity would be where I start at this point.

[drycamper]

Thank you, Chuckster. I may have answered my own question. I just went out and checked all the cells and I’m getting from 1225-1240. That is the best I’ve gotten, that I can remember. I had unhooked the batteries from the trailer and use the Ctec to recondition, 2 days ago. I think they push the batteries better than the trailers converter, even without reaching the recondition level.
Batteries are two years old. Light usage. Thanks again for responding.

[ChuckS]

I am currently using two Costco GC2 batteries that are now starting their 7th or 8th year is service. They are as good now as they were when I installed them.

The converter on my Alpine charges and maintains them with zero issues . The converter is OEM WFCO 75 amp 3 stage unit.

The fifth wheel sits stored at my house from late Oct thru mid May every year with a 15 amp service being used to power the fifth wheel converter

The specific gravity of the old batteries for each cell measured 1.297 to 1.3 on each cell when I measured them last week during my annual spring prep work

[flybouy]

Are you running the batteries down until dead repeatedly? If you do, then with every total discharge the battery will not recover fully, loosing some capacity potential with each total discharge.

[drycamper]

It has happened, although not on purpose. I turn the battery switch off, but there is still a draw down. So, I have brought them down to nothing a couple times. I will check the power of my converter’s charging power.

Thanks

[JRTJH]

Originally Posted by drycamper

It has happened, although not on purpose. I turn the battery switch off, but there is still a draw down. So, I have brought them down to nothing a couple times. I will check the power of my converter’s charging power.

Thanks

The correct way to check the converter output is to disconnect BOTH battery cables (at the battery) and check the DC voltage at the cable ends with the trailer plugged into shore power. Your measurement should be 13.6 (+/- 0.2) VDC. The process is described in detail with troubleshooting steps if the voltage is not correct. Procedure is located in your WFCO Power Center Owner's Manual. If you don't have it handy, download it at: https://wfcoelectronics.com/product-downloads/ using your Power Center model number. If you have a solar system installed, be sure that it is turned off and not supplying power to the cables or you'll be measureing something other than "converter output"....

[flybouy]

Originally Posted by drycamper

It has happened, although not on purpose. I turn the battery switch off, but there is still a draw down. So, I have brought them down to nothing a couple times. I will check the power of my converter’s charging power.

Thanks

Intent doesn't factor in. It only takes a couple of times to of running a flooded cell battery down to effect the capacity for holding a charge. Campers without the new giggly box have parasitic drains even if an OEM disconnect is turned to disconnect the batteries. The only way to prevent the drain is to interrupt the negative side of the circuit. That means removing the negative to ground cable from the battery or installing a disconnect switch in that side of the circuit.

[drycamper]

Thank you "A" Team.

[MarkEHansen]

Also, you don't have to draw the battery to zero to damage it. It should never be allowed to go below about 50% state of charge. You should invest in a good shunt-based battery monitor, like the Victron Energy BMV-712 (which is what I have). It makes it real easy to see where you are with your batteries.

If it were me, I would seriously consider replacing those batteries now that they've been damaged. I think they are still less than $90/ea at CostCo.

[bgrhrdt]

Originally Posted by flybouy

Campers without the new giggly box have parasitic drains even if an OEM disconnect...

What is a giggly box?

[wrvond]

Originally Posted by bgrhrdt

What is a giggly box?

https://www.keystonerv.com/innovations/giggy-box

On travel trailers it's a Giggy Box
On fifth wheels it's a Brock Box

[bgrhrdt]

Thank you!