Reviving a dead battery

[crabjoe]

Years ago, I remember a mechanic friend of mine reviving some dead battteries by replacing the electrolyte. He would simply dump the old and replace with new ... then put it on a charger for a bit. I have no idea how long this revived battery would last.

Recently, I noticed there is something called a desulfator, so I picked one up. Based on what I've read, it seems this process works, but can take weeks or months. I went a head a bought one .. BatteryMider 1500.

I guess my question is ... does a battery that has had it's electrolyte changed work as well as a battery that's been desulfated? I'd like to know because if it works just as well, I'd rather just change the electrolyte and be done with it and use the battery minder as just a float charger for my boat batteries.

Thanks!

 

[sberry]

Personally I replace batteries. Some auto parts are now offering remans too about 1/2 price, may be worth a look. I am not messing with acid, buying acid, replacing it in a battery really shot on its last leg anyway. A few more $ and not need to mess with it for years.

 

[sberry]

I was so glad when all that went away with maint free for most stuff, same for points and carbs.

 

[kaymccampbell]

An acquaintabce of mine claimed to get a second 5 years out of used batteries. He had some welder like power supply and a recirculating acid pump thing going on. One day one of his pump hoses came loose and sprayed the welder with acid and the whole shed burned down. After that there was some crazy stuff about a government conspiracy and I kind of shied away from him after the cops took him away.

 

[saceone]

An acquaintabce of mine claimed to get a second 5 years out of used batteries. He had some welder like power supply and a recirculating acid pump thing going on. One day one of his pump hoses came loose and sprayed the welder with acid and the whole shed burned down. After that there was some crazy stuff about a government conspiracy and I kind of shied away from him after the cops took him away.

 

[mobiledynamics]

Batteries are sooo inexpensive in the grand scheme of things.....that may net you $20 if not less per year to own it...... Why even bother.

 

[TK-421]

I tend to shy away from acid, so I'd just get a new battery when the old one died.

 

[crabjoe]

My question isn't about the cost of replacement. I'm asking about reviving a battery... I don't care if it costs more or less... I'm wondering about the process and if it works. You can say I'm looking at it from a science fair point of view.

 

[mobiledynamics]

Every time you ~charge~ a battery, you are basically ~~desulphating~~ it..

 

[BADSIX]

I use to have an uncle that rebuilt batteries and i would go in and help him sometimes. now this was 50 years ago, but we would drain and flush the battery then melt the tar that sealed the cells to the case .when we pulled the cell out the lead would be half or more eaten away. I don't think your going to get much more life by flushing or using the desulfator . you my get a little more time but it might be better just to get a new one .
Jay D.

 

[gungatim]

de-sulfating works on some batteries depending on how bad they are. there is a point that de-sulfating no longer works. a good one is expensive and takes a while to break even. the cheaper ones don't work real well from what I've read (I researched this a few years ago and decided it's just easier to replace the battery) and you can make your own de-sulfator if you are electronics saavy...and no it's not the same as just changing out the acid which does more harm than good...

 

[crabjoe]

If a "New" battery sits for years ... can it be desulfated and be like new or will the lead be to far gone? Anyone know?

 

[mobiledynamics]

Wet cells lose about 1% of their charge per day.
AGM's lost about 1-2%% per MONTH FWIW, CrabJoe.

That is why they have datecodes on them as well....so manuf. make's sure their stock is fresh. I don't if any parts dealer do this, but I suppose some of the bigger places may have procedures in place top off any battery on the shelf based on X date since production,

 

[kbs2244]

Youtube is your friend on ways to do it.


BTW, for more info on all kinds of batteries than you ever even knew existed try,

http://batteryuniversity.com/

Warning!
This is not casual reading.
It is a collage level site.

 

[RossABQ]

A friend of mine "revives" them by dropping them about 4" onto concrete -- seriously! It knocks the **** that is shorting plates off. Works for a while.

 

[sberry]

Just because it can be done doesn't make it a good idea,,, ha

 

[crabjoe]

A friend of mine "revives" them by dropping them about 4" onto concrete -- seriously! It knocks the **** that is shorting plates off. Works for a while.

That sounds crazy! Now if I can get my hands on a few dead batteries, I might try a load test before and after a 4 inch drop. Right now, I'm testing that Battery Minder .. It's been on a dead battery since Saturday. I'm going to do load test to see how it's going this Saturday. I friend of mine is suppose to give me his mower battery. In that one, I might try swapping the electrolyte to see if that works... I might not get that one till late Spring, when he pulls his mower from storage and replaces the battery..

 

[ZRX61]

I've bought zombie batteries back from the dead with a Battery Tender where a regular charger did nothing. Sometimes takes a while but they appear to be just fine afterwards.

Tender already paid for itself by making my m/c batteries last twice as long

 

[matt_i]

Tender already paid for itself by making my m/c batteries last twice as long

This. I have it on anything that's not a daily driver. Never monkey with dead or low batteries now and have only replaced two that had at least 10 years on them. I'm happy with that lifespan.

 

[sberry]

I would have to count exactly but have 25 or 30 in service in the summer. Every year I replace some. Its amazes me sometimes. My Dad pulled up to the door in a cart as while back, come in for coffee, went back out and the battery must have croaked on the way here, dead, nada.

 

[Warrenator]

Also you forgot the magic additives, like vx-6 or this stuff: http://www.amazon.com/dp/B000AMBOA8/?tag=atomicindus08-20

I have not used. I do have two of the electronic desulphators you can find on ebay, supposedly they work well. The last two batteries I had to swap out were from a bank of 6 volt golf cart batteries, they had been run dry and the cases were bulged at the sides and top where the terminals poke out of the case. I think those were too mechanically damaged to save. Moral of the story, check your electrolyte levels.

I used a battery minder on my Dad's minivan, took a week but brought it right back from the dead.

 

[rattle_snake]

The plates in a battery degrade over time and although a 'dead' battery can have it's life extended with new acid, that's not the battery I want 100 miles from home. The stuff that has flaked off at the bottom also contains part of the acid. Since you can't run current though it to released back into solution, adding new acid can improve performance.

Heat cycles shorten the life of lead acid batteries. note the outer cells usually have the lowest electrolyte level.

 

[Tree Cutter]

Anyone know which battery load tester I could buy that is inexpensive? Or do I need to buy a real good one for it to be accurate?

 

[sberry]

This is an HF super tool. It has to be on the top 10 50$ I have ever spent. Outright eliminates so much guess work so fast.