DIY pwm desulphation idea, need advice

[electro]

I have a ~ 1.5 yr old car battery, not to sure on the AH, but judging by its weight, i'd say upwards of 70ah capacity when new.

It was left connected in a non-running VW bug, and something in the cars wiring caused a short, or discharged the battery. Its my fault for neglecting it for this long, but its a relatively new battery. When i pulled it out of the car it was reading ~10.5v. Not good at all. I charged it with a standard car battery charger, at 5a overnight, then again at 2a, and it won't go above 12.4/12.6v after being charged. I popped the caps, and sure enough there was that sight that burns the eyes, white sulphate crystals on the lead plates. So its got some sulfation issues.

I ordered a morningstar solar pwm charger, and intend to use it with a 20w panel and a sepic to keep my solar panel voltage output stable, since under 13 its wasted, and over needs to be buck converted down to a charging voltage to keep a nice float charge on it and prevent desulphation. Witha 20w panel in northern california winter conditions i assume it will take a long time to desulphate this way. I'll prob end up hooking up a 15v 2-3A dc source to it so it desulphates a bit faster.

But my question is, i have a pwm dimmer for led lights, adjustable with a rf remote. Its rated at 8a 12v. I also have a ac/dc adjustable 12-15v 5a power supply. I want to try and see if i can use this to desulphate the battery a bit.

Can anyone advise me what voltage i should set the power supply at? I plan on running it at 13.5v 90% pwm to start, and see what they cell's voltage is after a few hours of charging, obviously keeping a close eye out for gassing/heating.

Is this a viable idea, or should i just wait for my morningstar and use that?

The only reason i ask, is these pwm dimmers are under $10 bucks, and all you need is an adjustable power supply for pwm charging if it works like i think it would.

Heres the link for the pwm dimmer, i got mine much cheaper, but its the first ebay listing i could find for the model i have-

http://www.ebay.com/itm/PWM-DC-12V-8A-RF-Remote-control-LED-Dimmer-/250964810854?pt=US_Stage_Lighting_Controllers_Dimmers&hash=item3a6eab1c66

[Sunking]

Sorry to say but no charger of any kind is going to fix that battery. . An EQ charge is what you want, but it will not work.

[inetdog]

I have a ~ 1.5 yr old car battery, not to sure on the AH, but judging by its weight, i'd say upwards of 70ah capacity when new.

It was left connected in a non-running VW bug, and something in the cars wiring caused a short, or discharged the battery. Its my fault for neglecting it for this long, but its a relatively new battery. When i pulled it out of the car it was reading ~10.5v. Not good at all. I charged it with a standard car battery charger, at 5a overnight, then again at 2a, and it won't go above 12.4/12.6v after being charged. I popped the caps, and sure enough there was that sight that burns the eyes, white sulphate crystals on the lead plates. So its got some sulfation issues.

I ordered a morningstar solar pwm charger, and intend to use it with a 20w panel and a sepic to keep my solar panel voltage output stable, since under 13 its wasted, and over needs to be buck converted down to a charging voltage to keep a nice float charge on it and prevent desulphation. Witha 20w panel in northern california winter conditions i assume it will take a long time to desulphate this way. I'll prob end up hooking up a 15v 2-3A dc source to it so it desulphates a bit faster.

But my question is, i have a pwm dimmer for led lights, adjustable with a rf remote. Its rated at 8a 12v. I also have a ac/dc adjustable 12-15v 5a power supply. I want to try and see if i can use this to desulphate the battery a bit.

Can anyone advise me what voltage i should set the power supply at? I plan on running it at 13.5v 90% pwm to start, and see what they cell's voltage is after a few hours of charging, obviously keeping a close eye out for gassing/heating.

Is this a viable idea, or should i just wait for my morningstar and use that?

The only reason i ask, is these pwm dimmers are under $10 bucks, and all you need is an adjustable power supply for pwm charging if it works like i think it would.

Heres the link for the pwm dimmer, i got mine much cheaper, but its the first ebay listing i could find for the model i have-

http://www.ebay.com/itm/PWM-DC-12V-8...item3a6eab1c66

Several problems with your DC PWM dimmer:

1. The output will need to be at least 15 volts to do what you want with a 12 volt battery.
2. The desulfator/charger will have to be capable of high voltage, high current pulses if it is to have any effect at all. Your device is current limited.
3. Although there is little hard evidence that desulfators work, or at least that the results they produce are dependable batteries, there is strong advice about what it takes to get one to at least appear to work. The LED dimmer you list is not what it suggested.

I suspect that your idea of how "desulfation" (as opposed to ordinary PWM charging) works is incomplete.

[Beanyboy57]

I suspect that your idea of how "desulfation" (as opposed to ordinary PWM charging) works is incomplete.

Several people are claiming that you can desulphate a battery and have posted video's on youtube showing how they did it. It's obvious that a few of them do not really know what they are doing but others seem believable .
One guy uses a 1amp trickle charger/desulphator that he made himself, initially then he uses a converted laptop charger (20v) to charge a desulphated 12v battery. He says it takes about 1 day for every 0.5kg (pound) to work, so a 40lb battery would take 40 days to desulphate. Before he begins though he thoroughly checks the battery to see if it is worthwhile saving. It's interesting to watch the process and the amount of effort that some people put into trying to revive 'dead' batteries.

[PNjunction]

So its got some sulfation issues.

Save some time and grab a NOCO Genius 7200 charger. If the battery isn't too far gone, it will burp the battery voltage up to the point where it will accept a normal charge. Then manually follow up with the 16V boost charge. If it feels that boost isn't making any headway, it will just quit and inform you. The manual even tells you that if the boost charge wasn't successful, it is best not to spend any more time on it.