Battery Desulfating - Does it work?

[M-MAN]

I went to start the mower for the first time this year a week ago. Engine barely turned over so I hooked up the battery tender to charge it. I noticed the date was 5 years old so I thought it was a good time to see if desulfating actually worked. I left it hooked up for a week. It showed fully charged and was still desulfating. Unhooked it and turned the key. Click. Tried again Click click. It was worse off after charging and desulfating for a week than it was before I started. Granted after 5 years it's past time for a new battery but the desulfating making it worse has me confused!

Thoughts???

 

[leroy in ne]

Connections clean? including both ends.

 

[rustred]

you need a new battery

 

[guido]

M-MAN

Get your volt meter out. 12.6 volts is a fully charged battery. Check the voltage after it does not start.

Sometimes the problem is loose valve clearance. Check also for voltage drop at the starter lug.

Check for voltage on top of the battery, should be none,

Guido.

 

[rustred]

it has to be load tested, have 12.8 volts or showing full charge dont mean the battery is good.

 

[circus]

I found a month on a maintainer worked better than a desulfator. Forever on a maintainer better still.
After using the desulfator button on my battery charger the battery always needed to be recharged. Does it work? Doubt it.

 

[da.bees]

There isn't a sure fire way of bringing old batteries back from the grave but slow charging and maintainer absolutely preserves and extends battery life. And I'm talking about quality chargers like Deltran,not $5 with coupon chargers from Harbor Freight. Other than allowing battery to set for prolonged periods less than 100% charged,the worst thing you can do is quick charge. Even boost start then driving to recharge is hard not only on battery but alternator as well. Feel the alternator after doing that, it will near blister your hand unless it's shot and not capable of designed charge.

 

[M-MAN]

I know I need a new battery. That's a given. What I want to know is why it lost power while desulfating? That shouldn't have happened. If desulfating actually helps the starter should have turned a little faster even though the battery is shot. Instead it didn't turn at all while it did before the desulfating. Desulfating actually hurt the battery.

BatteryMINDer Model 2012. 2 amp charge rate. Not an el cheapo. It desulfates the entire time it's plugged up.

Didn't see the point of a load test. This is the first mower battery I ever had that lasted over 2 years so tossing it won't hurt my feelings at all.

 

[Blackhole49]

Hydrogen peroxide.

 

[wp6529]

I recently got a charger with a desulphator function and it does appear to have helped revive a few batteries and there were a few more it couldn't save.

 

[jaoneill]

(quoted from post at 13:14:06 03/16/23) I went to start the mower for the first time this year a week ago. Engine barely turned over so I hooked up the battery tender to charge it. I noticed the date was 5 years old so I thought it was a good time to see if desulfating actually worked. I left it hooked up for a week. It showed fully charged and was still desulfating. Unhooked it and turned the key. Click. Tried again Click click. It was worse off after charging and desulfating for a week than it was before I started. Granted after 5 years it's past time for a new battery but the desulfating making it worse has me confused!

Thoughts???

I have several BatteryMinder maintainers that supposedly have an automatic desulfating cycle. Batteries that I use these on for 6 months of the year last 10+ years.
Also have a newfangled 14 amp, auto desulfate charger that kicks into desul mode if a battery has less than a 20% or so charge in it. This charger has salvaged a few older batteries for me; ones that would lose their charge if they sat unused for a week or two. Those that it resurrected are all still going strong. One success story desuled two years ago is a 15 year old battery in the payloader that has been sitting out in the gravel pit since September and spun right over the other day as if it had a new battery.
I've also had some batteries that it didn't help one iota.

This post was edited by jaoneill on 03/16/2023 at 02:14 pm.

 

[sotxbill]

Agree... desulfating does NOT charge the battery, it only cleans the plates.. SO yes, you must charge it fully after a desulphate cycle. BAD NEWS.. if sulfate has hardened, you cant bring it back.. GOOD NEWS, if its still soft, the high frequency pulsing will help liquify the sulfate and your battery will come back some or all. A battery mho conductance or internal resistance meter will show the before and after.. again usually with some or a lot of success. However it the coating has harden, your not bringing back the dead. Its not a bad ideal to run the cycle every six months or so on your batteries if you can remember. I probably see a 70% success rate on bringing back batteries on the tractors that still crank, but crank slowly. ymmv.

 

[504]

Just a guess,your smart charger will not charge a dead battery. You may need to charge it with a conventional charger, and then use your maintainer.

 

[kcm.MN]

I was given a battery some years ago. Was an Interstate marine battery, but also rated to use as a starting battery. It was less than a year old. Trouble was, it wouldn't take a charge. Voltage never got above 5V.

I took the battery home where it sat for several months. Then I ordered me a new battery charger. It has a desulfate mode on it. I ran it through 3 desulfate cycles over a period of several days.

WOW! It has been several years, and right now that battery is in the back of our town truck....just in case our truck battery is dead. We now have a good spare battery close at hand. It's also easier to use that battery to help someone needing a jump, especially if they pulled into the parking spot.

Forgot to mention, this is the battery charger I got:
https://www.amazon.com/STANLEY-BC25BS-Automatic-Maintainer-Alternator/dp/B01BYFSUJW

This post was edited by kcm.MN on 03/16/2023 at 04:19 pm.

 

[jaoneill]

(quoted from post at 20:14:51 03/16/23) Just a guess,your smart charger will not charge a dead battery. You may need to charge it with a conventional charger, and then use your maintainer.

You are correct. I have a simple wall plug style 1 amp charger that I use to get enough juice into a dead battery so that the "smart" box will do its thing.

 

[kcm.MN]

Re-read your post again. Another possibility is that the starter solenoid needs replacing. Might be able to just clean the contacts, but I've been told that solenoids can last anywhere from a day to several years, but that eventually they all need replacing.

Take your battery in to be load tested. That will tell you if it's the battery or not. This would be my first move, as having it tested is free. If the battery is good, next look at the solenoid.

 

[Welding man]

I have a SNap-On Battery charger that I paid close to 1000 bucks for. When you hook a battery up, it will immediately tell you if it is sulfated. If it is, it may take several hours for it to take charge. 90% of the time it will bring one back to life. Occasionally it will not.

 

[TerryfromSWIowa]

My smart charger says to disconnect battery before desulfating cycle.

 

[circus]

(quoted from post at 16:14:51 03/16/23) Just a guess,your smart charger will not charge a dead battery. You may need to charge it with a conventional charger, and then use your maintainer.

If my smart charger dies I'll just throw it away. If my 60 year old Schumacher dies I'll fix it no matter what.

 

[Mike(NEOhio)]

I see desulphating mentioned a lot here. Can anybody explain the process or how they work. The way I see it is all any charger can do is push some current through. I'd like to know.