TECHNICAL--Deep Cycle Battery

[john59]

We got back from our 40+ days in the KEYS and DIS, also other parts of Florida.

I put our 5r to bed around the end of April. I went back (to where) we store it and gave the 5r a once over 2 weeks later. I checked the Deka Rv/Marine deep cycle on the battery monitor in the trailer. Full Charge.

I went over yesterday and the battery was deader that a door nail. I left an outside light on.

Depending on how long the battery took to discharge, it has been dead the better part of a month.

I have 6amp charger. Can this battery be brought back from the grave. The battery is less than a year old.
john

 

[ElementCamper]

Maybe, but not likely especially if it was below freezing for any time where you store the RV. A dead battery is a battery that will very likely have frozen and busted if below freezing for any length of time.

All you can do is check the fluid levels (if that type of battery i.e. flooded cell) and hook it up to the charger. Then replace it if it won't take a charge.

 

[ftwildernessguy]

You have nothing to lose by trying, John.

 

[BigDaddyRog]

I doubt that their were anyfreezing temps during May....I would bet you could spring her back to life with a day or two of charging....aint gonna hurt to try.

 

[bradisgoofy]

As long as it did not freeze, check the case for evidence of bulging sides, and it is a wet cell deep cycle battery, you will need to hard charge it to get it to come back. The 6amp won't be enough, you need to hit it hard with 10 or more amps to clean off the plates that have probably oxidized after sitting discharged. This link will give you some very good info on batteries.

 

[john59]

It got a bit cold, but we did not have a hard freeze. Battery appearance looks OK.

Things are starting to look better on my deep cycle battery.

Right now, after about 14 hours, on my 6 amp, my hydrometer is showing about 60% charged. At about 6 Hours it still did not look good. All cells are reading about 60% at 14 hours.

I am going to leave it on for about another 10+ hours, check the reading, see how close I get to 100%, then let it sit in the garage and check it daily for a week. After a week, if it is holding the charge, I will put it back in the 5r.

If needed, I can borrow a 20amp and give it a real hit, but things are starting to look good with the 6 amp.

Thanks for your input.
john
PS: I have a gut feeling. All is gonna be good.

 

[john59]

Again, thanks for your input on screwing up or unscrewing my deep cycle problem. I had 2 deep cycles in my bass boat for 13 years. When I sold the boat, the batteries were still holding at 75%. If you stay awake and don't screw up these batteries can last a long time.

Summary: All on 6 amp charger.

Six hours on 6 amp charger. No change.
Fourteen hours. 60% recovered.
Twenty four hours. 75 % recovered. Battery is not heating up.
Going to try another 10 hours, keeping my eye on battery heat and charge %.

Note: My little 6 amp is charging at about 2 amps after 24 hours. I think this is normal, i.e. as the charge builds amp input drops. I saw this with the batteries in my bass boat.
john

 

[ftwildernessguy]

Do you have a multitester, John? Fully charged, your battery should read about 12.7 volts if it is reasonably healthy.