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12-26-2008, 04:55 PM #1
OT Bringing a Dead Deep Cycle Battery Back to Life
We just acquired a locomotive. (see thread in Antique forum about it). It has a 32 volt system and there are four Interstate deep cycle batteries on board. All of the cells are empty. No electrolyte visible yet the plates do appear moist. The locomotive last ran in the spring and then was parked, so I think the electrolyte just evaporated over the summer.
What can I do to try to bring these batteries back to life? I pulled them out of the locomotive and they are here at home where I can put a charger on them. I'm not going to do anything until I get some advice from someone who knows what to do.
12-26-2008, 05:21 PM #2
If the cases haven't cracked fill them with distilled water and try a low amp charger (1 to 2 amps) to see if they start to take a charge. Do not use a large charger at first. If the plates have sulfated there are web sites on how to build a special charger (look for homemade electric bike sites) to reverse the sulfate process which apparently really works. Good luck, Dave
12-26-2008, 05:21 PM #3
I can't give you a definitive answer but I can tell you where to look for one and make a few hopefully helpful comments.
You need to buy the book "Secrets of Lead-Acid Batteries from Lindsay Publications.
(Still in print, I think)
I don't think battery electrolyte evaporates all that much. I think the previous owners forgot to add distilled water on a regular basis to replace water lost during charging. (Lost by being broken down into Hydrogen and Oxygen)
I'll tell ya, this don't look good. I've seen a lot of batteries that died because stuff flaked off the plates, fell to the bottom, and eventually built up and shorted the bottoms of the plates. Uncovering the plates at the top, as you describe, cannot be a good thing.
Can these batteries be dismantled? I've actually seen my father, an old-time electrician, repair lead-acid batteries by lifting the cells out and combining good cells from two dead batteries to make one good battery. The easiest ones to repair have TAR (actually asphalt) holding the top of the cells in place. You melt the tar to get them open.
[I only saw Pop do this once during my lifetime, to make up a custom center-tapped 6V/12V battery. He sealed it up with aquarium cement, the type used on metal-frame aquariums. That material might itself have become rare.]
My grandfather's notebook talks about actually re-applying some sort of lead paste (I think an oxide or a sulfide) to the plates of a worn battery, but I believe in his day the batteries did not have "separators" between the plates which make this impossible in a battery from modern times.
Best of luck with this. JRR
12-26-2008, 06:34 PM #4
I've had batteries go completely dry, I assumed all the electrolyte evaporated, but it was always after sitting for many years. Seems odd to have it happen in less than a year. were they in high temperatures where they were sitting? Maybe that could cause it all to evaporate so quickly.
I would turn the batteries upside down to make sure they really were empty, and try to get all the crud in the bottom of the cells out by flushing with water to make sure they are not shorted. Some people recommend using baking soda and water to clean out the crud, and to clean the lead sulfate off the plates that accumulates from sitting discharged, I've not tried it myself. If the batteries are on their last legs, I imagine the baking soda could potentially clean all the material off one or more plates and render the battery useless. Refill the battery with fresh electrolyte and it should work fine, at least for a while. How big are these batteries?
12-26-2008, 07:09 PM #5
Sulfuric acid, the active component in the electrolyte, does not evaporate, only the water. You would need some rather extreme temperatures to break down the acid, which would then form sulfur trioxide SO3 + H20. All you need at this point is to add distilled water and begin the charging process, and hope for no shorted cells. I would agree with Mud that an electrolyte change is not going to hurt, but do it after you have agitated the cells with a charge. You don't know the condition of the batteries before, so if you add new electrolyte, then charge, you may wind up with with more sulfate being put back into the electrolyte than you want. Battery chemistry is rather finicky.
I would not recommend adding any baking soda. As you know, this is going to neutralize the acid, and lead acid batteries are a lot like an automotive oil filter. No matter how many times you turn it upside down, you never seem to get it all out. Any baking soda trapped between the cells will immediately neutralize the new acid. The only compound you might consider adding is EDTA, which is available on the net, that supposedly aids in the dissolving of sulfate on the plates. Hopefully, if you can get it charging to the point that all cells are actively bubbling, then you can be reasonably assured that you have stirred up the gunk enough to pour out the old electrolyte and start over. If you get 'em bubbling, I'd leave 'em that way for a couple of hours before you do the change.
12-26-2008, 07:18 PM #6Sulfuric acid, the active component in the electrolyte, does not evaporate, only the water.
12-26-2008, 07:34 PM #7
I would be surprised to find it completely dry. The acid is hanging around the bottom, with most of it trapped between the plates. In some cases it may be so trapped as to appear dry, but it's still there.
I keep a jar of concentrated acid around to adjust electrolyte. I created it by simply leaving the lid off of a jar of acid that was poured out of a battery and setting it on the window sill in the sun. In a few weeks you will see the level drop drastically, then stop. At this point, you have very little water left to evaporate. I was amazed at how much the level dropped from the original. It's certainly not hard to visualize how much of that acid would be absorbed if I stuffed a bunch of plates in the jar. The level would practically disappear.
12-26-2008, 07:41 PM #8
Given enough time, could the acid dry up(evaporate)? Example - I parked a '36 Ford pickup in my barn in 1973. (Gonna get back to work on it soon - y'know.) Earlier this year, I dug it out and got it running again. The battery that was in it was new in '72, and now is as dry inside as a box of cotton balls. Turning it upside down produces no liquid, dragging a q-tip over the plates gets no moisture. It was untouched in the meantime, under the floorboards, caps on tight. Where did the acid go?
What percentage of acid is in battery electrolyte?
12-26-2008, 07:50 PM #9
Well, I guess if we're talking in terms of 36 years, then I suppose nothing is forever. I have only broken down sulfuric acid with high heat, enough to create sulfur trioxide vapor along with one molecule of water vapor, which, much to the dismay of the occupants of the building, they found out that one molecule of sulfur trioxide blends with one molecule of water in saliva and returns to sulfuric acid. I was banned from the lab for several months after that.
Anyway, I can imagine that the same process could occur over time. Sorry to say I didn't devote any research to a 36 year time interval. Definitely an interesting question, though.
12-26-2008, 08:55 PM #10
You can still buy 8v deep cycle batteries, although your local battery dealer may have to special order them. Rather than spend a huge amount of time trying to resurrect dried out cells of unknown vintage, invest a couple of $$ and get some new ones that you know will work.
12-26-2008, 09:08 PM #11
The sulfuric acid was likely converted to lead sulfide (sulfate) in your 36 Ford pickup, hence the dry battery.
As for baking soda in a battery I've heard people swear by it although it would neutralize the acid some. One theory I've read is that the bubbling reaction might clear the short between the plates.
As for rejuvinating a sulfated battery pulse chargers are also available commercially and again, appear to work. Dave
12-26-2008, 09:17 PM #12
Sorry, Mud. I missed your question. Anywhere from 10% to 30% depending on state of charge. I gauge it by specific gravity at full charge, so I'm not well versed in concentration levels.
12-26-2008, 09:25 PM #13
WATER evaporates, and batteries self-discharge. More of both when hot.
So a dry battery either
2) self-discharged and dried out (meaning it is now sulfated to the max)
3) was drained for storage, hopefully in charged condition.
Since a deep-cycle battery has a lot of volume below the plates, if it is TRULY dry, it would HAVE to be due either to #1 or #3. Once the acid got below the plate level, it would no longer self-discharge, and there should be acid left.
12-26-2008, 09:35 PM #14
The best way to fix this is to post yet another appeal for donations to the "save the batteries/save the locomotive" fund. Collect enough dough to buy new batteries and save all the old derelict iron in the country to put in the museum. Said. Done.
12-26-2008, 10:34 PM #15
Do not add acid to batteries until you know the state of charge. Fill with distilled water and charge to the max. If you add acid instead of water, your specific gravity may be too high, too much acid. This is rough on the plates. If your specific gravity is low, hook up and charge. The acid is still in there, probably in the plates unless the batteries were dumped. If you charge the batteries all the way and still have low specific gravity, as a last resort you can try emptying the cells and filling with new electrolite, but don't hold your breath.....Joe
12-26-2008, 10:48 PM #16
+1 Joe. I agree
12-26-2008, 10:49 PM #17
fill them with distilled water, and put a charger on them
after they get to where they are gassing well, showing bubbles
take a specific gravity test with a hydrometer, and chart each cell
continue charging until there is no further increase in specific gravity
you will need to check with the manufacture to determine the original specific gravity that it was built with,
after they show no further increase in specific gravity, then you have an idea what happened to them, if they come back to about what the oem spec's them at then you know the batteries lost their water and were not simply drained of electolyte.
if the specific gravity is very low, close to that of pure water, they may have been drained after being fully charged and flushed with distilled water,, that would be a very good thing. all you would need to do then is drain all the water and refill with the proper electrolyte and they will probably be ok.
if they have been allowed to sit with low electrolyte, acid concentrated because of excessively strong acid,, they won't be worth messing with in my opinion.
the dry portions of the plates will be oxidized and forever damaged and will not recover to normal levels if they recover at all.
i suspect that they have been charged, drained and flushed so that they could be stored dry,, hopefully that is the case.
it is very unusual for the batteries to dry out in such a short amount of time otherwise.
hopefully the case is they prepped them for dry storage, if not they likely are not worth the effort to try and recover.
12-27-2008, 12:32 PM #18
Two years ago I got two completely sealed 12 volt deep cycle batteries on an electric wheelchair that had been stting on a carport for over a year.The batteries were tested and were dead as a stone.Because of the price of replacements I decided to try and recharge them.I had no way of knowing their inside condition because of the type of battery.I started out with a 2 amp charge overnight and still got no activity on the voltmeter.Put 'um back on two amp and left them for a solid week and noticed the chargers had started to come up.I took them off the chargers for a couple of days,let them set and then put them on a 10 amp charge.I noticed a drop on both bateries so I switched back to 2 amp for another week.After the second week at 2 amp The chargers had come up to around a half charge.I immediately switched to 10 amp and after another two days the batteries showed a full charge.I then took them to Battery Source and had them load tested and was told their was nothing wrong with them.Been using them ever since with no problem other than the occassional recharge.
12-28-2008, 09:34 PM #19
Well it wasn't as bad as it seemed. I added distilled water to the cells and as soon as I started pouring the level came up over the top of the plates, so I don't think the plates dried out. Each battery showed a voltage of 5.3 to 5.4 and I can get one ball to float with the specific gravity tester. I have a 6 volt car battery charger going on one battery, a Tungar Rectifier (GE product from about 1920) putting 9 volts to another, and a homebuilt variable voltage power supply on the third battery. The fourth was charged a bit yesterday and is at 8.4 volts now.
Maybe tommorrow I'll hook all the batteries back together, set the variable power supply to about 34 volts and let them charge for as long as it takes. All of the cells do bubble when charging, a good sign.
I checked my notes and I last saw this locomotive in service back in May, so at most those batteries have been sitting for seven months. The main battery switch was pulled so there was no load on them, they just discharged by themselves.
One other thing, the batteries are Interstate USRM8V-26 deep cycle marine. They are listed as having 1050 CCA so apparently they were designed for use as starting batteries.
12-28-2008, 10:19 PM #20
Several years ago I was touring an off-the-grid house and the owner showed me the bank of used electric fork lift batteries in the back of his garage. He got them cheap and dosed them with epsom salts once a year. He had been using them about 8 years.
I have had very good luck with ordinary lead acid (with caps and liquid in the cells) "dead" batteries set on the curb. I bring them home and put a level teaspoon of epsom salts in each cell and fill to mark with distilled water. I then put on a 1 to 2 amp charge to see if we get action. If it charges, I check with a digital volt meter to see if we get about 14 volts.
If it does that it goes in the truck, keep an eye on acid level, keep the terminals clean, and once a year give it a shot of salts.
One of my clients had a Die Hard battery in a Volvo that kept going down because she didn't use it much. She had me take it to Sears, they pronounced it dead, gave her credit for unused time and a new battery.
I asked for the old one and did the above. It has been in my 318 engined Dodge van for 4 years, and starts every time, even after sitting 3 - 5 months.
I have been able to make two out of three curb side batteries work.
Last edited by paul39; 12-28-2008 at 10:23 PM. Reason: correct word