Is it possible that if you drain a battery all the way down, that it might not want to recharge? Maybe change the polorization... or remove it altogether?

Ryan

Yep a totally drain battery can sometime not want to take a charge.
I have a battery charger that conditions and cleans the plates that can charge a battery that normal will not take a charge from being drained 100%

One thing you can try is putting a teaspoon of epsom salts in each cell of the battery if you don't have access to a high end battery charger - the salts will clean off the battery plates in much the same way as a product called "recharge" but at a fraction of the price.
I've had success with this many times when collecting import cars from the wharf (myself and my father used to import and sell cars ex japan) as they would often go flat on the journey out to n.z.

Interesting. I managed to leave the amplifier on for a few weeks in the old truck that's parked in the garage. Dead'ern a doornail. It won't take a charge either.

Ryan

How long have you tried to charge it? I have had some batteries that were dead for extended periods (a couple cases, years) and was able to get them to come back by leaving the charger on them for a day or so. Of course, you don't do that by hitting them hard, but rather a slower charge. Some never recover, some do. I had a battery I took from a crusher car that had sat there for years before I hauled it take a charge after putting a slow charge on it for around a day. That would be the longest dead battery I have revived, but have had some that were down for months wake up doing that. Put them on the fast charge, and they generally fry first.

I had it on a 2A trickle (the lowest setting on my charger) for about 36 hours. Not even a click on the starter. Not even a dim bulb in the cab when the door was open.

Ryan

Sounds like it is done...

A word on battery warrantees now... Walmart dropped their warranty from the free replacement time and prorated extended time to just the free replacement time, and most of the rest of the battery sales world is following suit. No more 8-9 year warranty with 3 year free replacement, it is now just 3 years free replacement and nothing more. My manager told me that on Monday, I just thought that will piss off a lot of people for a while... He told me it is pretty much industry wide, so not going to be any real options against it. And they hiked the price yet another $10...

Get 2 batteries (one is the bad one) hook them up with jumper cables. Hook up your battery charger. The good battery provides "flow" that "fools" the charger. Eventually it burns off the sulfates on the plates, and it'll start taking a charge (an old used car lot trick)

blacksnapon said:

Get 2 batteries (one is the bad one) hook them up with jumper cables. Hook up your battery charger. The good battery provides "flow" that "fools" the charger. Eventually it burns off the sulfates on the plates, and it'll start taking a charge (an old used car lot trick)

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Neat trick never heard of that one before.

blacksnapon said:

Get 2 batteries (one is the bad one) hook them up with jumper cables. Hook up your battery charger. The good battery provides "flow" that "fools" the charger. Eventually it burns off the sulfates on the plates, and it'll start taking a charge (an old used car lot trick)

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Now we're talking... I'll give that a try.

Ryan

Have to remember that one... Quick question though, for clarification, do you hook the charger to the good battery or bad? I am thinking bad, correct?

Fellro said:

Have to remember that one... Quick question though, for clarification, do you hook the charger to the good battery or bad? I am thinking bad, correct?

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Shouldn't matter if they're hooked up Parallel.

Shouldn't but it can unfortunately. Good batteries can be damaged by bad ones when hooked continuous, like on diesels. Seen it happen many times in actual loaded use.

[ Eventually it burns off the sulfates on the plates, and it'll start taking a charge (an old used car lot trick)[/QUOTE]



Thats where i learned the epsom salts trick - on the wharf (dock) we would just drop in a teaspoon of salts per cell , jump start the car , hang the dealer plate on the back and drive the 200km home - by the time we got there the battery would be working fine in probably 80% of the cars we did this to.

I used to work at a local GM dealership that taught me every dirty trick in the book.

once you get it going or get a new battery go out and get one of those battery tenders. We did that on Pam's Mustang. The one we got has a plug that attaches to the battery and sticks out from under the hood. Just unplug and go, when you're done driving plug it back in.

I don't see how connecting 2 batteries in parallel would force one to take a charge.
And what Scott said...a battery tender or battery tender junior are great ideas, cheap and will extend your battery life without any danger of overcharge.
I'm not going to get in a big discussion about battery fixes for dead batteries, I suggest some reading at manufacturers sites or some books on chemistry. A dead battery can reverse it's polarity and once a typical lead/acid starting battery has been fully depleted it's life is reduced.

DNFXDLI said:

I don't see how connecting 2 batteries in parallel would force one to take a charge.
And what Scott said...a battery tender or battery tender junior are great ideas, cheap and will extend your battery life without any danger of overcharge.
I'm not going to get in a big discussion about battery fixes for dead batteries, I suggest some reading at manufacturers sites or some books on chemistry. A dead battery can reverse it's polarity and once a typical lead/acid starting battery has been fully depleted it's life is reduced.

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Essentially, the resistance of the sulfates prevent the plates from taking a charge (this is a simplification, but its close to that). The addition of the extra battery allows "flow" of the electronic charge, effectively fooling the charger. I've even had 4 batteries hooked up in parallel for difficult cases. Now, agreed, the "recovered" battery hasn't the longevity of better conditioned ones, but it'll work temporarily (all a used car dealership needs is 6 months more)

I see what you are saying now...I kinda forgot that the newer electronic sensing chargers will not output current unless they see a requirement for said current...so the addition of a battery or more would set that draw up.

I found my answer. I noticed today that the key in my Dent had been left on towards the acc. position. And I'm not sure how long.
Probably up to 3 weeks. The battery is dead and won't take a charge, since about 8 AM. I might try the epsoms salts tomorrow.