Maybe this will be helpful, maybe not, but thought I'd post about my experiment anyway:
I have a restoration battery that's weak - prior owner let it run low on water, plates exposed - and after it sits, reads just over 11 V.
Figured I'd see if that desulfation gizmo in the MA article would work.
Charged it back up from 11.3 - 12.6 is as good as it gets - and then connected the gizmo per instructions.
Back & forth between the gizmo and the charger, seems to be gaining .1 - .2 V per day when I test it after it's sat for a while.
After it sits overnight, it'll read 11.6 with the voltage tester, which is accurate on other batteries & charging systems.
So far, I'm 5 days into this; maybe the battery's too damaged, but I'll play the game for another week or so.
Between the gizmo instructions and the article, seems it could take a couple days to a month.

Kinda hoping to avoid the mess of gutting the battery for the hidden-upgrade deal, but we'll see how it plays out.

Tony's Garage on UTube had an episode which showed how to rejuvinate a weak battery with an Arc (stick) Welder, it seemed to work, have not tried it myself. Do a search.

Sister in law had a dead battery in her car. Would jump start the car and show charging, but wouldn't hold a charge after the car shut off. Battery test under load was not good. Can't recall exact numbers, but was junk. I have a Battery Minder 1510 that I tried to use to desulfate on. Battery was too weak for it to work. I charged the battery with a standard charger and got the voltage up, but would slip over night. I put the battery on the charger and when it hit enough volts per the Battery Minder manual (10.5V), I hooked that up and let it do it's thing. After a few days on it, I pulled the Minder off and let it sit for a few days. Seemed to hold a charge around 12 Volts. We put in a new battery anyway, but used the dead one to experiment with.

Can you give some help on the search? I’m a little slow on how to search. Thanks

https://www.youtube.com/watch?v=8CxFpIoKwy0&ab_channel=UncleTony%27sGarage

EDIT: ^^^ Copy and paste that into your browser.

Direct link --> https://www.youtube.com/watch?v=8CxFpIoKwy0 Battery Desulphated with stick welder <--

I can think of potentially less painful ways to kill yourself.
Ever see the result of a battery explosion?

I have used several different battery chargers that claimed they had the ability to clean the plates and restore an old battery. I tried them on more than a dozen batteries and never got a single one back to working condition.


As far as the arc welder idea goes, I have seen a couple batteries explode. Not worth the risk to say the least.

Question about the "desulfator gizmo":

This devise supposedly works by periodically zapping the sulfated plates with "high-frequency AC"...so I'm wondering if this will damage the electronics in modern cars. The articles/videos I've seen don't mention if the battery has to be disconnected from the car (thereby losing all the presets and computer memory) during the zapping process.

Here is the best comment under that video.

I disconnect the battery on any car with an ECU if I am going to use a charger at more than 20 amps for this very reason.

I read somewhere that a bat should be charged a min of 17-18 volts for the first few minutes, like a shock thing, knocks the sulfate off.?

Free technical information on lead acid battery charging

https://batteryuniversity.com/article/bu-403-charging-lead-acid

sample quote

Much has been said about pulse charging of lead acid batteries to reduce sulfation. The results are inconclusive and manufacturers as well as service technicians are divided on the benefit. If sulfation could be measured and the right amount of pulsing applied, then the remedy could be beneficial; however giving a cure without knowing the underlying side effects can be harmful to the battery.

end quote

I am 60% confident this Pulsetech brand name charger has extended the life of my 12 volt lead acid batteries

https://www.amazon.com/Pulsetech-Xt...8-1&keywords=desulfating+charger#Ask

I know it is using high frequency current because I can hear it using my “DC to daylight” wide coverage radios.

It makes some of the WORST buzzing on radios I have ever encountered.

I monitor the watts of power it uses with a Kill-O-Watt meter.

sample quote from the
Questions &. Answers at Amazon
on the Pulsetech charger

Most of these 'smart' chargers use the same integrated circuits from Texas Instruments.
Those ICs have safety features to stop the charger from pouring amperage into a bad battery (or worse) and creating a safety problem. If the charger is hooked up to the battery with reverse polarity it will not charge (i.e. backwards, negative connected to positive, etc). If the battery voltage is too low it will not charge. Many people use a 'dumb' constant current charger to bump the battery voltage up to minimum then connect the smart charger. Also, there is at least one timer that will disconnect power if the charge takes too long, usually after about a day or so, then it displays the 'bad battery' light. Unplugging the unit from the AC then reconnecting should reset this timer and allow another charging cycle. After the battery is fully charged and being maintained, this charger periodically checks to see if the battery will accept amperage, I.E. need more charging time. This check and any subsequent charging will bring on the charging light for the time that the charging circuit is active for this purpose.

end quote

One of the things I was told after I bought my airplane was to take the battery out every year and hook up a small 12 V light to it and kill the battery completely and then use a low amp (2 to no more than 6 amp) battery charger to charge the battery from 2 to 5 days. Stop charging after it reach a voltage above 13.3 V. disconnect from the charger for two to five minutes
That worked for me for many years, those battery are very small and have to start a 540 C.I. low compression flat 6 cylinder in the airplane with a 4 to 6 ft. long cable to the starter solenoid from the battery
The battery was mounted behind the baggage compartment for weight and balancing it to get the center of gravity in a safe position no matter how the aircraft was loaded: up:
I did need to do weights and balance checks when I first got the airplane to learn how to load it safely

1st off, I have no business doing anything with a stick welder

I'm just doing this as an experiment, and the battery is not in the car.
My typical charging deal is limited to a 2A maintainer, though that's not enough for this battery - it needs the 10A setting on an actual charger.
The charger's 2A setting only results in a "bad battery" light coming on, and no improvement in V reading.
Checking battery voltage, it never shows better than 13.6V (charging), drops to 12.6V when charger's disconnected, then decreases from there, but never worse than 11.5 now.
It'll sit at 11.5 for 10 hours or so now, whether the desulfator is connected or not.

Interestingly, this resto battery never vents vapor through its caps; my other one does when on the maintainer.
The other one also had insufficient level inside it when I got the car.
It "runs" 12.6V (charged) down to 12.0V if left to sit a couple weeks, Ground cable disconnected.

12.6v is about 80% charged

https://pveducation.com/solar-concepts/battery-state-of-charge-vs-open-circuit-battery-voltage/

Yup, and that one hasn't been a problem starting the car it's in, even at 12.1V.
The weaker one will start a car, but I'd rather it never drops below 12V.

Just watched Tony fix his battery, I have a few to try this on. If you’re scared of not wearing a seat belt, lead in paint, muratic acid rust remover, loud noises, grinding stuff, by all means don’t try this!
BTW a battery charger is a smaller version of an arc welder anyway

This old (25+ years) battery charger I have has a start boost setting, a 10 amp setting, and a 2 amp setting. The meter reads plus to minus to 30 amps. If you put it on start boost, it will peg the 30 amp meter, but will also reduce down to 10 amps down after about 45 seconds to a minute on boos (unless you are actually boosting the battery and have a big draw). Its brought back about 1/2 of the questionable batteries I've connected to it by using the boost before it switches to the 10 amp charging.
I'm going to miss it when it finally dies.

Truth.