battery-desulfator

[kelsol]

I came across this today:

Best Battery Desulfators: Fully Restore Your Battery’s Capacity

Looking for battery desulfators? Our team of experts narrowed down the best battery desulfators on the market. Read this review and save yourself time and money.

www.thedrive.com

The recommended 'Batteryminder' is over $100 , and according to its reviews can (but not necesseraly will) revive even completely dead batteries.

I have no experience with this kind of thing, though I do store 'dead' batteries for having potentially more value in lead content that core refunds.

I do know that an older method was to turn the battery upside down and whack it good with a rubber hammer to loosen the oxidation/buildup and remove potential shorts. And possibly also replace electrolyte. Not to my liking.

So the issue is whether these desulfonators are worth the bother, as well as potential expense.
1. There are cheap chinese versions on Ebay for around $20. Any good?
2. Anyone have a working schematic & instructions for building what is essentially a pulse generated trickle charger?
3. In lieu of 2, any links to info on how to test functionality on these gizmos with a scope?
4. Please note that I do NOT intend to use these reanimated doorstops as part of a functional battery bank. Perhaps a couple in series for temporarily running an old UPS for outside cameras and LED lights. (150W max. ). Or maybe with a scrapped solar panel.

 

[Substrate]

The reality as you've mentioned as #4, this is largely a waste of time.

That review linked is totally bogus from somebody just reading back the box marketing, and having no knowledge of desulfation really.

If you are still wanting to play with trash, then you'll need to spend $$ to get a charger like the BatteryMinder, which tests the battery on a frequent basis, and will stop, even if desulfation seems to be making progress.

Unlike cheapskate $10 DIY "zappers", these chargers have charge profiles and testing to help prevent the duds from going into thermal runaway whilst you are trying to desulfate. So sorry - you'll need to make the investment if you want any sort of reasonable result or conclusion (like they are a total loss from the outset!).

Likewise the safety with other quality chargers with desulfation like Tecmate/Optimate, and PulseTech.

Note that PulseTech and BatteryMinder (not battery tender!) use a sweeping pwm overlayed on top of the main charge current, and are NOT using high-voltage pulses, which many diy'ers tried to pawn off with triangle, square, inverted waveforms and such with absolutely NO scientific background as to what is actually going on.

Please note that *REPUTABLE* manufacturers never say that they can reclaim dead batteries, but that they are supposed to be used in conjunction with a battery maintenance program. Only reviewers, influencers, and the totally clueless promote the idea of reviving dead batteries - not knowing that sulfate *expands* and breaks batteries internally.

The moral is that YES, if you want to play with trash, even with your proposed limited application, you'll have to spend the money on an advanced tool, not a $10 DIY trick that makes the duds go into thermal runaway.

 

[Substrate]

P.S. - instead of a scope, if you have a portable am radio handy, you tune it in between stations, and bring it close to the battery terminals. Very close, like less than a few inches. Because the units that rely on frequency rich harmonics, rather than high-voltage spikes (like the Battery Minder and Pulsetech), you can easily hear the desulfation taking place, changing in amplitude and frequency...

 

[-g-g-g-]

Having had electronic desulphation boxes attached to my last two sets of batteries from new and seen no difference in performance nor longevity, I conclude these are pointless devices.
They were free, attached to two lorry batteries on one of the second hand lorries I owned. I can't recall the make, and the paint has rubbed off the aluminium during the last fifteen years. I do know that at the time they were advertised at over £100 each. They put out AC pulses at various frequencies and follow some random cycle. These were made for the RAF originally if my memory of the sales waffle is correct.
They certainly haven't harmed anything. I kind of forget the fact that they are there.

My last set of 4 Rolls S500ex 6V lasted 7 years, my present set are now the same age but in better health due to increased array so better charging and lower cycling.

There's only one guaranteed way to revive a dead battery, works every time, faultlessly.

Fill it to the brim with water, pond water will do.
Take it to a scrap metal dealer, exchange it for about 50p per kilo (hence maximising the weight with water) and put the cash towards new ones.
You can earn more by breaking it open and selling the lead then dumping the plastic case or the "traditional" method of combustion, (good luck finding anyone who will accept it into the waste stream).

What you need to remember, is that there is no safe limit of lead in the human body.
So these old batteries are best recycled properly and never consider any attempt to play with the contents.
I've been handling scrap metal since the 1970s and I've tried every means to revive dead batteries in that time so I like to think I have a degree of expertise.
As stated above, sulphate breaks the plates, indeed is or rather, was the plates. It settles into the bottom of the battery as it falls off and defies anything to return it to the plates it once was. (other than thermal recombination in a foundry).

 

[12VoltInstalls]

Four+ years back, first solar system was a windyNation kit with a 30A pwm.

I didn’t buy batteries yet and was impatient. I had some grp31 marine batteries 8+ years old that wouldn’t hold charge but stuck ‘em in place. Had enough to run coffeemaker the next day, but at sundown plummeted to 11.x volts.

I was busy with work and left them in place and since they were running the coffeemaker and water pump urgency waned.

About a week or so later they were 12.8/12.7 at sundown and had started holding that overnight. I wound up running them all summer with great success. By November had rented a place for the winter and didn’t check the electrolyte like I had been. By December when I went back they were mostly dry.

Yes, damaged batteries, reduced capacity, but the solar charging ‘fixed’ them whereas my 15A ‘smart’ charger didn’t do much to make them work.

Lead acid are ‘recoverable’ to a point sometimes but damaged batteries will never be repaired.

 

[kelsol]

It looks like Batteryminder, although Chinese - and apparently not an unbranded knockoff - would be the better choice.
These are also trickle chargers of around 2A.
The question that pops up is how this would work as maintenance mode in storage in a 6 12v (fla) parallel system. They apparently have y-spliiters , but would these even be functional in a parallel system?

 

[-g-g-g-]

Lead acid are ‘recoverable’ to a point sometimes but damaged batteries will never be repaired

Agreed, in fact one of the main advantages of solar charging is the charge and rest period that allow tired lead batteries to recover.

My concern is with the wild stories banded about that you can reverse aging with Device X or Mystery process Y.

Once a cell is short or failed nothing other than physical repair will have any effect.
Once it has dropped sulphate into the bottom, nothing will replate the plates back to original condition.

I've just recharged a block of sulphate that was a 100Ah leisure battery that I used to start my generator with, then forgot about. It's gone from 9.4V to 12.79V static. I took it off charge a month ago and it's held that right until now - I just checked it to see. I doubt it has 550Wh it claimed as new but it kicks my Yanmar L100 over sharp enough. I had written it off but it has revived sufficiently to be useful.
However, I have two Rolls 30H-108M that nothing can resurrect despite being attached to 160Wh panels for six months. I haven't looked at them but beyond holding the tarpaulin sheet over the log pile I think their useful days are over.

I read a lot about these desulphators when I discovered the two I own, attached to my lorry. There's some evidence that they can assist in extending battery life but mostly bench top comparisons if my memory serves me right.

In the real world they might have been assisting my Rolls S500EX batteries to last longer. They were fitted from new and have always been there. My electrolyte is balanced across all 12 cells. I've never carried out an equalisation charge as I charge at the maximum recommended rate 2.5VPC bulk, 2.19VPC float.

I still think they are primarily fairy powered and output rainbows. But who doesn't like rainbows?

 

[efficientPV]

If they worked that well, the batteries would last forever on PWM controllers. That said, I restore batteries with my water heater which has high current pulses. I always need an extra battery or two and I get them from town recycling. Usually, batteries ignored over winter. The ones with most success have less than 0.5V which are dried out gells. Just a science project, ask me again in 5 years.

 

[Substrate]

Yep - they do work, but their scope is limited, often misunderstood - perhaps by the vendors themselves who forgot the past work.

We have to go like 40-50 years back, and look at the original John E. Galli patents to truly understand the frequency-based technique used by Battery Minder, Pulsetech, and some others.

Essentially, it was discovered that instead of the age old method of "zapping" the sulfate with high voltages, and taking active material with it, using a frequency-based algorithm, it was possible to get to the hardened sulfate by manipulating the EI (Electrolyte Interphase) layer.

The EI layer should be well known to us using lithium - the "SEI" layer, where that layer can be filled with inorganic gunk over time, shutting down the battery prematurely due to abuse etc.

In the lead-acid battery the EI layer doesn't solidify - it's the hard sulfate from undercharge that reduces capacity.

So if we can manipulate the EI layer sufficiently enough that current can reach the hardened sulfate from the inside, it can be charged, and not just riding on the surface being ineffective. And that's where the frequency-based technique - originally just a single frequency but later a sweep of range was introduced.

The PROBLEM, is that this is to be part of a PM measure at the start, rather than at the end of life. It is most beneficial to AGM, which are chronically undercharged. It doesn't replace proper charging, which is the *first* step.

Because if you get to it too late in time, the expanding hard sulfate has already damaged the battery by breaking grids, warping and shorting plates, etc.

Hence the need for advanced chargers like Battery Minder and Pulsetech, which ALSO keep an eye out for these damaging problems that can crop up with ignored dud batteries, with their charging profiles, when the sulfate is finally removed and while "cleaner", is still damaged!

Kind of gross, but one might think of it like dental-health. Let your plaque harden for too long, where the toothbrush is ineffective and a dental pick (high cv voltage) might remove it, but also take enamel too in the process. If you can get to it from underneath chemically, (aka frequency based desulfation) it might take much more time, but won't take the enamel. However, if you've never brushed your teeth, (improper charge) the desulfation / cleaning will expose much more serious primary problems. Yech!

 

[Substrate]

Let's have some FUN with the topic by going into the wayback machine!

Not understanding the patent, or how the EI layer works, was a prime target for discussion. Back in the days when the internet was still most closely associated with military computers.

The naysayers, not having access to any real equipment, would attach their output of one of their stereo speakers to the battery terminals, and play everything from Led Zeppelin to Bach to their battery. Some would claim that a certain "genre" of music was effective.

They didn't realize that this frequency pulse was an *additional* waveform riding over the top of the main charging current, and was chosen specifically for purpose, not something you play back from your stereo.

Hard core bench engineers would immediately whip out studies conducted by the Navy concluding that "pulse charging" was at most a panacea. They too, never read the patent and simply attacked - hijacking the word "pulse" to sway consumers who have no education that these two things were completely different. Apples and oranges.

Even today, the "P" in pwm is entirely misunderstood, and everyone and their grandma come out to comment pro or con about it.

That may be the reason that the manufacturers NEVER go into the EI-layer detail because for the most part it is a glossed-over eyeball kind of thing. Like explaining the SEI layer in lithium batteries.

 

[chrisski]

I'm no longer a fan of battery desulphation being a cure to battery problems. Where I looked at it was on car batteries. I had a Pulseech device and the battery lasted no longer than the prior set. 2.5 years in sunny Arizona.

Decades ago when "everyone knew how to deslfate a battery" the lead cells were a lot thicker. Those could be desulfated easier through different methods like equalization or even replacing the acid itself and cleaning with watter and baking soda and pouring new or filtered sulfuric acid back in the cell.

Now the modern car batteries have cells that are extremely thin and basically once the damage is done and not providing power, too late to recover. The corrosion is too much.

Google searches tell stories of how to save a battery through certain ways, and most just can't be recovered. They're usually followed by, "I knew a guy who tried it and it only worked on 1 of 10 modern batteries."

For solar batteries, I do believe in proper maintenance of Flooded Lead Acid Batteries by following the manufacturer's specs and equalize when specific gravity as measured by a hydrometer when its out of balance, or to do a periodic equalization as per specs.

 

[circus]

The only gizmo I ever found that made any difference at all is $10 battery maintainers. Prevents sulfation in seldom used batteries. Extended my misc batteries from a couple years to over a decade. Might cost $2 per year to power. Prevents freezing too.

 

[chrisski]

The only gizmo I ever found that made any difference at all is $10 battery maintainers. Prevents sulfation in seldom used batteries. Extended my misc batteries from a couple years to over a decade. Might cost $2 per year to power. Prevents freezing too.

The prevents freezing thing got me at first, but it does keep the specific gravity higher when charged so a better charged battery needs a lower temp to freeze.

I don’t deal with many days I worry about freezing in sunny AZ.

 

[32 volt boater]

Four+ years back, first solar system was a windyNation kit with a 30A pwm.

I didn’t buy batteries yet and was impatient. I had some grp31 marine batteries 8+ years old that wouldn’t hold charge but stuck ‘em in place. Had enough to run coffeemaker the next day, but at sundown plummeted to 11.x volts.

I was busy with work and left them in place and since they were running the coffeemaker and water pump urgency waned.

About a week or so later they were 12.8/12.7 at sundown and had started holding that overnight. I wound up running them all summer with great success. By November had rented a place for the winter and didn’t check the electrolyte like I had been. By December when I went back they were mostly dry.

Yes, damaged batteries, reduced capacity, but the solar charging ‘fixed’ them whereas my 15A ‘smart’ charger didn’t do much to make them work.

Lead acid are ‘recoverable’ to a point sometimes but damaged batteries will never be repaired.

So the question is do PWM solar chargers pulsing work to desulfate ?

Ok again I never think of anything first !

www.instructables.com/Quickly-Make-Any-PWM-Solar-Charge-Controller-Into-/

 

[sunshine_eggo]

I've had limited success restoring old batteries with "pulse desulfation" of FLA. In each case, the battery would hold great voltage, but it's capacity was a small fraction of rated - 10-20%. It typically took weeks to accomplish.

I've had overwhelming success restoring degraded batteries with equalization charging of FLA. I mean HUGE gains. Restoring capacity to 90%+ rated from 50-60%. Capacities were tested with controlled 25A discharges to measure Reserve Capacity rating.

I believe pulse desulfation offers potential benefits in maximizing battery life, but if you're doing this, you're just paying attention, and that alone goes a long way towards maximizing battery life.

 

[wme]

FWIW
2 ea DuraCell EGC-2 batteries (Sams Club) 300w solar, old MPPT controller, unknown brand. Pulsetech, Power Pulse.
4 years on, batteries still going strong. Visual on plates, they are clean.
Proper maintenance on batteries

 

[Substrate]

I dig it - Pulsetech or Battery Minder works great with proper maintenance, but hard to prove because of that.

Then again, no underhood car battery lasts in Arizona. And even if you could totally desulfate it overnight, because hard sulfate expands, it physically damages the battery. So you wouldn't want to use it anyway.

I was using it with my pure-lead agm's. EV car days when nimh was up and coming.

Even though I was maintaining my Genesis agm's well, and nearly slept with the Enersys technical manual under my pillow, there is a built-in issue with fanatical agm maintenance. To actually achieve recombination, the negative and positive plates are slightly different in capacity.

That means that at some point, the larger plate (forget which polarity was which), even with fanatical maintenance, will start to sulfate while the other is just fine.

A procedure was developed to counter this - and I won't even describe it - it was pulled from later Enersys tech manuals because if not done properly, hurt the batt. Us EV geezers called it "dancing on the head of a pin". You would very quickly overcharge after absorb was truly finished to get that bigger plate desulfated, but not long enough to cause damage to the already fully charged opposite plate. So hard to automate, we just did a little "zing".

In lieue of doing that dangerous procedure, I thought I'd use the Pulsetech to accomplish that instead. Along with proper maintenance of course.

Of course, I can't prove that it helped. My reason for using it seemed logical though.

 

[Substrate]

In lieue of doing that dangerous procedure, I thought I'd use the Pulsetech to accomplish that instead. Along with proper maintenance of course.

Of course, I can't prove that it helped. My reason for using it seemed logical though.

My memory jogged - now I remember.

Back in the day when NiMH was the up-and-comer for EV's, a LOT of heavy research went into pure-lead AGM studies in order to find ways for fast-turnaround so that the potential EV user doesn't walk the AGM's down in capacity by not achieving a full charge and sulfating hard little by little. It's a physyics thing, you can't rush that.

A lot of research went into manipulating the EI (electrolyte interphase) layer - the microscopic boundary between the plate and the electrolyte. In this case, it's not solid, but is still a layer nonetheless, and getting through that efficiently was of utmost importance - but this research material was hard to find unless you read a lot of the ALABC white-papers, pushing hard for lead so that nimh would be ignored.

These guys - read the mission statement about lead acid:

Consortium for Battery Innovation | » About us

batteryinnovation.org

It is here, in the EI layer that the Pulsetech and Battery Minder work. Instead of attacking hardened sulfate directly with high-voltage pulses, a frequency-dependent waveform is superimposed on the dc charging current, "stirred up" the EI layer and got to the sulfate through the back-door of the EI layer so to speak.

Some hangers-on realized that directly zapping hardended sulfate was more damaging than beneficial, but merely "guessed", and provided all sorts of super-neato square, triangular, and other "magic" waveform crossing their fingers and heavily promoting it to consumers who like that sort of eye-candy.

Heh, how do you put that into a consumer brochure with making eyes roll? Or enough time has passed that even the makers forgot how it was supposed to work.

Getting through the EI layer was *never* intended to restore batteries already damaged by hard sulfation expanding, it was to help prevent it from happening in the first place. It's only *consumers* who push recovering trash, or simply shady little diy voltage zapper circuits who have no concept of what an EI layer is.

Unfortunately, the trash-recycler crowd, and diy-zapper market, and the ones who want to maintain *after* sufficient damage has been done - who have no idea of how to manipulate an EI layer, yet alone even know of it's existence, put ALL desulphators into the snake-oil family.

Which is funny - most anyone who does LFP, at least hears about the SEI layer (solid junk buildup). When I transitioned from pure-lead to LFP, the electrolyte-interphase was not a stranger to me.

Gosh - my very first Enersys Pure-Lead technical manual (2nd revision) had this futuristic looking EV on the front and talked about "ongoing research" to find the perfect fast-turnaround charge algo, although I don't remember if it discussed the EI layer. You had to hit up the white-papers about it.