Getting a ddeeaadd battery going again?

[jackhartjr]

I have a deep cycle battery that is totally dead.
Is there a way to get it going again?
When I put the charger to it it goes straight to 'CHECK'. 
Thanks
Jack

[gumpy]

Use a dumb charger. One that just puts out low current, like 2 amps.  charge it slowly for a couple days, then ramp it up.

Alternatively, connect the dead battery to a good one (parallel connect) overnight with jumper cables. This should bring it up some as the charge will trickle from the good battery to the bad one. Then put your smart charger on it. Don't forget to charge the good battery up again, too.

[Hi yo silver]

Sometimes you have to give them a "kick" start; charge them at a fairly high rate for a few minutes initially, then reduce it to a lower rate.  For example, twenty to 25 amps, then down to perhaps ten to 15 amps.  I like to keep just enough solution in the batteries to keep the plates covered, it will expand of course, as it warms up.  Sometimes that's easier said than done, depending on where your batteries are located.

Dennis 

[Hi yo silver]

Hey Jack,

Let us know what works for you!

Dennis

[jackhartjr]

Thanks for the replies.  I am going to give Gumpy's idea a try, starting with paralling the good on overnight.  I will let everyone know what happens.
If it does not work...I may just try the one where you pour the acid out and fill it with water and epson salts.  I will get better clarification on that first.
There are actually two of these batteries in the same state of ddeeaadd.  The go in my nephews bass boat. 
Thanks again!
Jack

[belfert]

I had a set of batteries that would only charge to 20 volts no matter how long I charged them.  I had to charge them at 50 amps for maybe ten minutes and they would go to 24 volts and start the bus.

I had to replace the batteries.

[Kristinsgrandpa]

  Check the archives as this has been brought up several times. I think the consensus is that the plates get sulfated and it needs to be burned off. The only way to do this is with a charger that pulses (desulfation mode). I bought one on ebay that does it automatically, (smart charger).

There are several knowledgable people that frequent this board that can give you a better idea about what you're up against as it takes weeks to do this on some batteries.  (Sean where are you)

Chargers that have this capability usually are advertised as having a desulfation mode.

Ed

[Kwajdiver]

Seems I may have the same problem.  Just removed 4 house batteries from the bus.  All read between 7.5volts and 9.5.  Just put the first one on a 10 amp charge.  Going to let it sit for an hour, check the voltage, then charge it over night on 2 amps.  Presently, it's drawing 5 (amps) on the battery charger meter.

We'll see what happens.

Bill
St. Petersburg, Florida