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batteries won't stay charged |
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ronnieb ![]() Newbie ![]() Joined: 24 Oct 2020 Online Status: Offline Posts: 10 |
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My batteries won't stay charged after reaching 12 volts with a solar panel nor will they charge after driving. What to do?
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GlueGuy ![]() Senior Member ![]() ![]() Joined: 15 May 2017 Location: N. California Online Status: Offline Posts: 2709 |
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What are you expecting? Batteries do self-discharge, even with no load. So expect to have to charge them at least once a month without a load.
Separate from that, there can be parasitic loads that will discharge a battery much more quickly. In extreme cases, maybe only a day or two. You need to use a DC-capable ammeter to see what parasitic load you have. The parasitic load on our RP179 is about 1/4 amp, or 250 milliamps.
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bp
2017 R-Pod 179 Hood River 2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost |
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ronnieb ![]() Newbie ![]() Joined: 24 Oct 2020 Online Status: Offline Posts: 10 |
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Hi Glue Guy, I do charge the batteries every month, but on this last road trip, the batteries were at 7.6 volts after driving 10 hours..not enough to open the slide. I hade to start my truck to operate it.
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Tars Tarkas ![]() Senior Member ![]() ![]() Joined: 14 Jan 2013 Location: Near Nashville Online Status: Offline Posts: 1454 |
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How old is the battery? Are all cells filled with water? Are all connections clean and tight? TT
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2010 176
FJ Cruiser |
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ronnieb ![]() Newbie ![]() Joined: 24 Oct 2020 Online Status: Offline Posts: 10 |
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Hey TT, The batteries are maybe 3 or 4 years old, I'm diligent about recharging them every month but on this last road trip I had to add distilled water.Still not able to keep a charge. I think my next move is to remove them and have them tested.Any other thoughts?
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Tars Tarkas ![]() Senior Member ![]() ![]() Joined: 14 Jan 2013 Location: Near Nashville Online Status: Offline Posts: 1454 |
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It's a bit of effort, but probably worth disconnecting every cable, from the ground on the frame, the batteries, and from the batteries to the converter, wire brush everything, and put it all back together. Then, if necessary, have the batteries tested. Could be something else, but that's probably what I'd do. TT
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2010 176
FJ Cruiser |
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jato ![]() Senior Member ![]() ![]() Joined: 23 Feb 2012 Location: Kewadin, MI Online Status: Offline Posts: 3349 |
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Once a lead acid battery has been taken down below 12.2 v it will be considered damaged to a point to where it will not hold a charge as long as hoped for. You are wise to take it out and have it load tested. I have been very careful, not allowing either of my 12v batteries to go below 12.2v before recharge. Batteries are: 14 yr. old Interstate deep cycle and a 4.5 yr. old Trojan T-1275. Even after not being charged for 5 months (northern MI) sitting directly on a concrete floor in an unheated garage the Interstate read 12.41v and the Trojan was at 12.56v.
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God's pod
'11 model 177 '17 Ford F-150 4WD 3.5 Ecoboost Jim and Diane by beautiful Torch Lake "...and you will know the Truth and the Truth will set you free." |
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GlueGuy ![]() Senior Member ![]() ![]() Joined: 15 May 2017 Location: N. California Online Status: Offline Posts: 2709 |
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+1
An old battery taken below 12 volts is "damaged". You might get away with that once or twice, but each time it takes a bit of life out of it. Taking it down to "7.6 volts", is serious damage, and that baby is probably toast.
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bp
2017 R-Pod 179 Hood River 2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost |
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ronnieb ![]() Newbie ![]() Joined: 24 Oct 2020 Online Status: Offline Posts: 10 |
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Thanks all for your support. I took the batteries in to be tested today, and yep, dead.Just shows I need to me more on top of checking the water levels and charging once a month.
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jato ![]() Senior Member ![]() ![]() Joined: 23 Feb 2012 Location: Kewadin, MI Online Status: Offline Posts: 3349 |
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The most important maintenance practice you can perform for maximum battery longevity is to not allow them to drop below 12.2v before recharging. As stated above my batteries go 5 months w/o charging sitting directly on a concrete floor in an unheated garage and they still perform well.
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God's pod
'11 model 177 '17 Ford F-150 4WD 3.5 Ecoboost Jim and Diane by beautiful Torch Lake "...and you will know the Truth and the Truth will set you free." |
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