lead-acid battery desulfator

[JoeTheJuggler]

So can these things really restore a bad battery or give longer life to a battery that's not holding as strong a charge?

If so, how do they work?

I understand the idea is that the metal plates react with stuff in the fluid and get covered in lead sulfate crystals, and the idea is to remove or reduce the size of the sulfate accretions, but how do these electronic things supposedly do that?

[Toke]

I am not sure what a desulfator is, but I do know that charging a battery can be quite complicated if you don't want to damage it.

Here is a link to the chargers we use onboard for our 24V backup batteries.

[Toke]

Rejuvenating the battery by sending high voltage pulses into it?
And you can buy a build it yourself kit on the net?
And somehow this have not been incorporated in the electronics for high end chargers?

I say woo.

BTW. A dead battery can be caused by the plates shorting due to the lead detrius collecting at the bottom. One way to fix that somewhat is to flush the cells out and refill with fresh acid.

[JoeTheJuggler]

Originally Posted by Toke

Rejuvenating the battery by sending high voltage pulses into it?
And you can buy a build it yourself kit on the net?

Or buy a ready made desulfator for $100 and up.

Quote:

I say woo.

It does sound like it, but I'd like to hear what the explanation is for how they're even supposed to work.

Some of the sites extolling the virtues of this device aren't actually selling anything.

Not that that means much--people have nothing to gain by repeating rumors, gossip, urban legends and other false information, yet that stuff happens non-stop on the interwebs.

[Toke]

Quote:

It does sound like it, but I'd like to hear what the explanation is for how they're even supposed to work.

Me too, my google-fu sucks. All I found was the bit about high voltage pulses, and that makes no sense to me, a charger can be programmed to do that.

An UPS for your computer comes with an usb plug for communication with your computer, I have not noticed any desulfator upgrade patches for download.

[Dan O.]

Sulphating is usually not a problem if the batteries are kept properly charged. If you do have a sulphate problem, raising the charge voltage for a short time can re-dissolve the sulfate crystals and help restore the battery. It can also help destroy the battery by corroding the plates and causing outgassing. For some good background on various batteries try this link.

As more households install battery backed solar systems, there will be a demand for keeping storage batteries running longer. Someday, someone will do the science and build a smart charger that will do the best job of restoring dead batteries. Sort of like an AED for batteries. I haven't found one yet.

Sulfating is not the only cause of a week battery. If the charge voltage has been too high (the exact voltage depends on temperature), the cells can dry out. One site I just ran into even shows how to open the cells and add water. The author there didn't know what he was talking about most of the time so I won't bother pointing to the page.

Most small UPS systems have a simple fixed voltage charger. They should at least provide a periodic equalizing charge but none that I've looked at do. I often fine one completely destroyed battery in series with a still useable one (though not suitable for any critical system at work ).

[BenBurch]

I believe that the USPTO has a policy of rejecting battery rejuvenator patents unless accompanied by a working model. At least they did ages ago.

[Dan O.]

Originally Posted by BenBurch

I believe that the USPTO has a policy of rejecting battery rejuvenator patents unless accompanied by a working model. At least they did ages ago.

http://www.uspto.gov/web/offices/pac...600_608_03.htm

With the exception of cases involving perpetual motion, a model is not ordinarily required by the Office to demonstrate the operability of a device. If operability of a device is questioned, the applicant must establish it to the satisfaction of the examiner, but he or she may choose his or her own way of so doing.

(showing off Google-fu)

[trvlr2]

They work. I own one.

They will not recover a shorted battery.

It will recover a sulfated battery, giving extra life to the battery.

I have a cheap Vector/tm battery charger with a desulfate setting. Many high end chargers and voltage regulators have a desulfate setting. The Vector is not anywhere as effective as the dedicated desulfator.

Most lead/acid batteries suffer from chronic undercharge. Sulfation will build on the plates over the normal life of the battery, reducing amperage output. Sulfation plus sensitivity to ambient temperature is visible alongside the roads, come winter-your car just won't start. There is usually nothing wrong with those batteries that a desulfation program will not fix.

Just keeping 30% of the automotive batteries out of the scrap heap, is a good environmental cause, albeit only for another 4 years, or so.

I got the desulfator because I hate dragging 8D batteries out of engine rooms. I am lazy and cheap.

[Dan O.]

I notice that Vector was acquired by Black and Decker a few years ago. Some of the Vector battery chargers are now part of the B&D product line. Conspicuously absent however is any mention of desulfators.

If these things worked as well as the testimonials say they do, why hasn't anyone done a proper scientific test and published the results?

[trvlr2]

Dano--I think they have. Done the tests. I sort of remember doing a bunch of research before buying my units. What I remember, is that a bunch of the information seems proprietary, and much of the data is closely held. Publishing? In a scientific journal? I don't know.
I can tell you this- not every battery can be fixed. Those with shorted cells, for starters. Anecdotally, I get 30% recovery.
What I mean , is that 3 of ten will go back out there, doing their job. After passing hydrometer tests, load tests. The others go to recycle.
I have not read too many testimonials lately. My (anecdotal) experience has been that testimonials are selected for positive results, negatives discarded.
Lead acid batteries have a lot of other caveats. Construction of the plates, case are very important. Operating temperatures, too. Maintenance of electrolyte, connections.
Charging is critical, to obtain maximum life. Maximum life can be a very long time, if proper maintenance is done.
Do you imagine your telephone company wants to change out their batteries every five years? They don't. They don't change the batteries, ever, unless it has a problem. And those are some very large 1.5 Volt cells. Verry large.
From the Black &Decker web site:
quote: ref 40 Amp charger
"Automatically selects ideal charging conditions
High frequency charging technology charges up to 2x faster than conventional chargers
Patented engine start, jump-starts vehicle within 1 minute
Provides pure DC output to provide a stable charge
Patented alternator check indicates condition of the alternator
Reverse hook-up protection prevents damage caused by incorrect terminal connections
Digital LED display shows battery voltage, diagnostics and fault codes
Microprocessor controlled automatically switches between charging mode and float mode monitoring for optimal battery life
Battery reconditioning improves the battery’s ability to accept a charge" .end quote
What do you suppose "reconditioning" means?

[Dan O.]

Originally Posted by trvlr2

Battery reconditioning improves the battery’s ability to accept a charge" .end quote
What do you suppose "reconditioning" means?

It doesn't actually say what "reconditioning" is. Perhaps they are talking about this...

http://peswiki.com/index.php/Directory:BatMax

*It "dissolves" the crystalization that causes battery life loss.
*Increases battery life and reduces charging time.
*Provides improved battery performance.
*Thousands of testimonials have been received.

[Hatchet]

I've had a little experience with this after installing and maintaining a few solar power systems for our observatories.

Most high end battery charges do include a high voltage charge phase called an "equalization charge". This helps to prevent "stratification" of the battery acid, where the sulphuric acid seperates from the water in the battery cells (because the sulphuric acid is heavier than water).

Charging the battery at high voltage (called an equalization charge) causes hydrogen to bubble through the acid in the cell, essentially stirring it up and reducing the stratification. This should only be done for unsealed flooded lead acid batteries. It is damaging to other types of lead-acid batteries and will reduce the battery life due to the outgassing of hydrogen, which can't be replaced (i.e. by adding distilled water to a flooded battery)

Most battery companies recommend an equalization charge either at regular intervals or when there are changes to the specific gravity of the acid (e.g. see here http://www.trojanbattery.com/Battery...qualizing.aspx). Just check with the battery manufacturer whether an equalization charge is suitable for your battery type.

The pulse-style battery-rejuivination chargers are aimed to reduce "Sulphation" in the battery, which is basically a buildup of lead-sulphate on the battery plates, reducing the available conducting area. As far as I know, the use of the pulse-style chargers is not recommended by battery manufacturers (at least I have not come across any literature endorsing them). Sulphation should instead be prevented by charging at the correct voltages and by not discharging below the manuafacturers recommended levels.

I have used these battery "rejuvinators" in the past and they have recovered batteries for a small time. However not enough for me to recommend them to others.

Cheers.

[trvlr2]

Originally Posted by Dan O.

It doesn't actually say what "reconditioning" is. Perhaps they are talking about this...

http://peswiki.com/index.php/Directory:BatMax

*It "dissolves" the crystallization that causes battery life loss.
*Increases battery life and reduces charging time.
*Provides improved battery performance.
*Thousands of testimonials have been received.

I think that is just what they mean.

Hatchet is correct, also. The equalization charge brings the 12/v nominal to 16.5/v for a period. Supposedly, this puts the crystalline sulfates back in solution. Also,this will cause outgassing, and will mix the acid/water better. Sealed batteries should not be equalized, as a rule. Sealed batteries (AGM) are picky about float voltage, as well.

All lead/acid cells are subject to thermal runaway, with sometimes interesting results.

Any new battery should be charged properly before use. The battery will self-discharge (sulfate) at about 1.5% capacity per month, varying with temperature. Depending on how long the battery has been on the shelf, there may be appreciable difference in its initial capacity as bought. For a time, sealed,dry-charged batteries were supplied to the public to prevent this. I assume(!?) that the practice was discontinued, because J.Q. Public is a moron, and not to be allowed to handle acid.

Charging correctly is critical. Not only do the high end chargers provide equalization settings, they also have temperature sensors which monitor the battery temperature and the alternator temperature, reducing amps/volts to prevent runaway and keep from cooking a high end alternator.
So, does a desulfator work? Yes, and no. Certainly folks at Xantrex and Balmar seem to think their customers can benefit from sophisticated chargers, regulators and alternators. ( Their customers are some of the cheapest, most demanding, on this earth. Blowboters, and solar power freaks.)

Does the high voltage pinger/pulser work? Yes, and no. It will not save all batteries. Some can be saved. Furthermore, just because a battery manufacturer does not recommend them, does not mean the device doesn't work. It means they have no comment, for whatever reason.

[JoeTheJuggler]

So it sounds like the answers to my questions about does this thing work and how does it supposedly work, higher charger voltage is meant to re-dissolve the sulfate crystals that have precipitated onto the electrodes. But since most no good batteries are probably shorted (and everyone agrees that desulfating won't fix a shorted battery), the ability of this process to restore a bad battery is limited.

Also it carries the risk of damaging a good battery, but I'm only talking about using it on a battery that already won't hold a charge, so the risk of harm isn't important.

And to the question why is that if such a thing works it's not already included in good chargers, the answer is that it is already in high end chargers, though maybe not with the name of "desulfator".

So is there no difference in what a desulfator does (higher voltage when charging) and what an "equalizer" does?

For automotive batteries, the charging system in the vehicle usually charges at a higher voltage anyway, I think, so does that mean they've all already got a built in desulfator? Or perhaps it has to be a higher spike in voltage no matter what the normal charging voltage is?

[Dan O.]

Originally Posted by trvlr2

Originally Posted by Dan O.

It doesn't actually say what "reconditioning" is. Perhaps they are talking about this...

http://peswiki.com/index.php/Directory:BatMax

*It "dissolves" the crystallization that causes battery life loss.
*Increases battery life and reduces charging time.
*Provides improved battery performance.
*Thousands of testimonials have been received.

I think that is just what they mean.

Check out the link. BatMax is total woo. Proving it worked would probably qualify for the MDC


Pulse rejuvenation may help some batteries. The problem is that without the backing of scientific tests, there is no distinction between the claims made for pulse rejuvenation and the claims made for the BatMax.

[JoeTheJuggler]

A couple of more questions:

On many of the sites that talk about desulfating with higher voltage, there's also talk about desulfating by adding EDTA to the fluid. Is there anything to that?

Is there a way to determine that a battery is shorted out rather than no good for some other reason? (Using say a volt/ohmeter, which is about all I've got.)

Thanks for the info!

[Dan O.]

One of the claims is that the high frequency pulses cause the large crystals to "crash". All of the claimants present the same photographic "evidence" showing the large crystals that magically disappear after applying the rejuvenator but none explain how they disassembled the battery and reassembled it without disrupting the crystals. It's being sold like woo even if it does work.

The pulses in the rejuvenator are a much higher voltage that the equalizer charge. Hazards could include increased potential for electric shock, damage to electronics if connected to an in-circuit battery and the possibility for arching which could ignite explosive gasses in the battery.

[Dan O.]

Originally Posted by JoeTheJuggler

A couple of more questions:

On many of the sites that talk about desulfating with higher voltage, there's also talk about desulfating by adding EDTA to the fluid. Is there anything to that?

As soon as you start adding something new to the battery you are probably doing more harm than good. Why didn't the battery manufacturer put it in to begin with?

Quote:

Is there a way to determine that a battery is shorted out rather than no good for some other reason? (Using say a volt/ohmeter, which is about all I've got.)

The easy measurements are the end of charge current, the open circuit voltage after being charged and the voltage under load. If a cell is shorted, you will be overcharging the other cells and the current will be too high. A dehydrated cell will show a higher than normal open circuit voltage. And sulphation or plate corrosion will increase the internal resistance so will show a lower voltage under load.

A better test is to measure the AC impedance over a broad spectrum. This has been found to give a good correlation to the actual battery capacity but requires more equipment and the correlation varies by battery manufacturer so it may be difficult to incorporate into a tester for consumers.

[JoeTheJuggler]

Originally Posted by Dan O.

One of the claims is that the high frequency pulses cause the large crystals to "crash". All of the claimants present the same photographic "evidence" showing the large crystals that magically disappear after applying the rejuvenator but none explain how they disassembled the battery and reassembled it without disrupting the crystals. It's being sold like woo even if it does work.

So they're trying to sell the frequency of pulses as what does the desulfating rather than just the increase in voltage?

The sentence I bolded sounds accurate. Even if it works--in extremely limited situations--it doesn't work for the reason they're claiming.

Still--I am interested in those limited situations. I've got 2 automotive batteries that might be no good due to exactly the kind of abuse that might lead to sulfation. I might try flushing them out (to remove any possible shorting crumbs), and then I would like to charge them at a higher voltage to see about desulfating them. I don't think I'll be buying or making a desulfator. I might see if I can borrow a higher-end charger than the cheap trickle charger I've got.

Originally Posted by Dan O.

As soon as you start adding something new to the battery you are probably doing more harm than good. Why didn't the battery manufacturer put it in to begin with?

I could imagine EDTA doesn't work as claimed, but this argument doesn't really wash. I also didn't evolve to have aspirin in my bloodstream, but in some conditions taking aspirin will "work" for one purpose or another. If you're dealing with a battery that won't hold a charge, doing harm to the battery isn't an issue. (Harm to one's bank account is definitely an issue!)

On one site, the claim was that EDTA somehow causes the sulfate crystals to fall to the bottom (not to dissolve--or maybe it was that they dissolve and then precipitate back out, but not on the electrodes--I disremember). That site said if you use EDTA you should then flush out and replace the acid. I think that site was selling an electronic desulfator though!

[trvlr2]

Originally Posted by JoeTheJuggler

So they're trying to sell the frequency of pulses as what does the desulfating rather than just the increase in voltage?

The sentence I bolded sounds accurate. Even if it works--in extremely limited situations--it doesn't work for the reason they're claiming.

Still--I am interested in those limited situations. I've got 2 automotive batteries that might be no good due to exactly the kind of abuse that might lead to sulfation. I might try flushing them out (to remove any possible shorting crumbs), and then I would like to charge them at a higher voltage to see about desulfating them. I don't think I'll be buying or making a desulfator. I might see if I can borrow a higher-end charger than the cheap trickle charger I've got.


I could imagine EDTA doesn't work as claimed, but this argument doesn't really wash. I also didn't evolve to have aspirin in my bloodstream, but in some conditions taking aspirin will "work" for one purpose or another. If you're dealing with a battery that won't hold a charge, doing harm to the battery isn't an issue. (Harm to one's bank account is definitely an issue!)

On one site, the claim was that EDTA somehow causes the sulfate crystals to fall to the bottom (not to dissolve--or maybe it was that they dissolve and then precipitate back out, but not on the electrodes--I disremember). That site said if you use EDTA you should then flush out and replace the acid. I think that site was selling an electronic desulfator though!

Joe: EDTA Not going to help you . Or the battery.
The tools you need are a good hydrometer,accurate voltmeter, distilled water, goggles. Possibly bicarb of soda, rinse water. Oh, a good 3 stage charger. Carbon pile tester?Pinger.
Your hydrometer is your big indicator and fairly accurately tells you the state of charge. It will also tell you if a cell is shorted. Any cell which indicates 25 points or more different from the others, is shorted.
(Warning: anecdote))I have recovered batteries that indicated SG 1.00. (I question the accuracy of my hydrometer.)Which is the same as water. Obviously, cells in the lowest condition will not respond to normal charger-the voltage is simply not high enough to get current to pass thru the electrolyte, or what little remains.

" Smart chargers" will rate the battery a total loss, and refuse to charge it. Enter the high voltage pinger. Pinging will have to go on long enough so that you get a voltage on the battery. Then use the hydrometer to check if you have an anomalous cell. If yes, junk it. If no, continue pinging. Monitor the voltage and the SG. Both will rise, over time. Voltage will peak, sometimes well over 17 volts, then fall off to a more normal voltage. During this time, SG will continue to rise. And, the battery is gassing merrily. Do not let it get more than a little warm, to touch. When SG rises no more- your battery is recovered and is fully charged. Takes me about a day with one that far gone. I also have a varistor on the battery lead which turns down the pinging during warm times.

The smaller pingers will take much longer, but will work, if they are like mine. Overheating is much less of a problem. A problem of dendritic shorting can occur with the lower powered units-If insufficient power is not applied, conductive dendrites can form on the plates, bridging them, effectively shorting the cell.

I am no chemistry major, but taking any of the sulfate ions, hydrogen ions or the lead ions out of the solution will logically decrease your battery's capacity.(EDTA, or other contaminant.)

It also occurred to me during my research, that even though a battery seems simple, many little-understood things go on in the cell. Or, if anyone really knows, the information is proprietary, and closely held.

Please note: this business of "is it the same as what a high end equalizer does" is a yes and no answer, AFAIK. Does the frequency matter? Idaknow. Some say yes, it is the resonant frequency of the sulfate crystal. Beats me. And I don't like that crystal woo, either. If it did not work as I have said, I would not say it. I wouldn't use it , either.
It is not necessary to know why it works, to use it. It is only necessary to know if it works.

This is not a self-charging battery circuit; nor, a Steorn machine, or H2O2. And, yes, if the next hundred batteries come up zippo, I will have to say, "It Don't Work." ( I will have learned a great deal about L/A batteries, though)

So, look at your bank account, judge for yourself if you'd like to play, get a hydrometer and goggles, hook a charger, and a pinger, go for it. You'll get more satisfaction, save money, buying a kit and assembling a pinger yourself. PM me , if you'd like some input.

[Dan O.]

trvlr2 brings up a condition where the "pinger" can help. When a lead acid battery is allowed to fully discharge, the electrolyte becomes just plain water. The sulfuric acid that was the electrolyte is disassociated and chemically combined with the plates. Pure water is an insulator therefore no current can pass through the battery to charge it. The pinger provides a high voltage spike that can disassociate the water itself and allow charging to begin.

The alternative method for starting the charging process has been to use a high voltage low current trickle charger. The low duty cycle pulse may be preferable because it won't have the DC voltage to drive undesirable chemical reactions.


If the pulse chargers really improved battery life, you would think that real scientists would have studied them. NREL does employ real scientists and is very interested in maximizing battery life but it doesn't appear that they have bothered to look at the pulse chargers. Instead, they have developed a charging algorithm that can triple the life of a common LA battery. Here is their paper and presentation.

[JoeTheJuggler]

Thanks for the info, folks!

[trvlr2]

Dan-o- Yes, that is true. If a high voltage trickle charger can be had, or, you can otherwise get the electrolyte to carry current, charging may begin.
As far as " why don't manufacturers or NREL study desulfators?"
I can imagine easily why manufacturers don't want to talk about the subject. They have already given instructions on proper charging and care, which if followed, from new, precludes the need
of a pinger. I might add, most of those instructions are not followed.
The NREL has to get funded on a project that someone else thinks is good 'bang for buck'. So, perhaps they will study the subject one day.
The study you cited was concerning VRLA batteries only. And, it was noted there, that how the batteries were being charged, wasn't the most effective.
Might I ask, why, do you think, batterymanufacturers missed that detail(s)?Tripling the life of the battery?
I suspect that it would have something to do with a business plan.

Also, could you please define, "real scientists"?

[Dan O.]

Originally Posted by trvlr2

Also, could you please define, "real scientists"?

Why, can't you tell the difference?

[trvlr2]

Originally Posted by Dan O.

Why, can't you tell the difference?

Well, I may have missed something.
Why don't you tell me what you think are "real scientists"?

Then we can maybe discuss papers presented to the SAE?

[Dan O.]

So, what's wrong with the scientific conclusions of this study:

TESTING ON STORED BATTERIES: During the Oakland University study, testing was also done on stored batteries to determine how PulseTechnology would affect military vehicles that sit unused for long periods of time. The batteries were stored at a constant temperature of 25° C (77° F) for 14 weeks. Some were equipped with Solargizers and others were not.

The final report lists the following results: "There is a distinctive difference in the charge capacity between these two batteries. A battery stored under the influence of pulsation retained its original capacity while the capacity of the battery stored without pulsation lost a considerable amount of charge. The decrease of charge capacity of batteries stored without pulsation decreased linearly with time. After 14 weeks the decrease of charge capacity accounted for about 25% of the battery's original capacity. In this same period of time, the charge of the battery attached to the Solargizer slightly increased. This is probably due to a reconditioning (reforming) process of the battery plates by continuous pulsation.

Hint:

http://www.pulsetech.com/products/Manuals/solcharger/solchg_manual.html

It continually monitors your batteries and if it drops below full charge, it recharges them to full capacity

[trvlr2]

Originally Posted by Dan O.

So, what's wrong with the scientific conclusions of this study:

TESTING ON STORED BATTERIES: During the Oakland University study, testing was also done on stored batteries to determine how PulseTechnology would affect military vehicles that sit unused for long periods of time. The batteries were stored at a constant temperature of 25° C (77° F) for 14 weeks. Some were equipped with Solargizers and others were not.

The final report lists the following results: "There is a distinctive difference in the charge capacity between these two batteries. A battery stored under the influence of pulsation retained its original capacity while the capacity of the battery stored without pulsation lost a considerable amount of charge. The decrease of charge capacity of batteries stored without pulsation decreased linearly with time. After 14 weeks the decrease of charge capacity accounted for about 25% of the battery's original capacity. In this same period of time, the charge of the battery attached to the Solargizer slightly increased. This is probably due to a reconditioning (reforming) process of the battery plates by continuous pulsation.

Hint:

http://www.pulsetech.com/products/Manuals/solcharger/solchg_manual.html

It continually monitors your batteries and if it drops below full charge, it recharges them to full capacity

Why don't you explain what is wrong with the cited conclusion?

Why don't you define "real scientists"?

[Dan O.]

Originally Posted by trvlr2

Why don't you explain what is wrong with the cited conclusion?

Why don't you define "real scientists"?

I already did, you missed it.

Now, unless there is something more substantive or someone has a real question, I think it's time to drop this thread.

[Toke]

seconded.

[trvlr2]

Ummm...No.

1.An effect was noticed. A claim was made.
2. A hypothesis was formulated.
3. Testing showed positive results.
4. A paper was presented to the SAE.

Real-world usage confirms results.

So, please answer the questions.

Who are the 'real scientists'?
What's the matter with the SAE?

Are you stuck on the wording of the blurb? Where the battery was supposed to be 'recharged'?

What?