this looks much similar than the last one you guys posted, http://hackaday.com/2009/02/07/desulfator-in-an-altoids-tin/ since you don’t have to modify a charger

Posted at 6:09 pm on Jul 5th, 2009 by sean

Interesting project. Is there any danger to it? There’s a lot of stored energy in a car battery, and treated improperly they have been known to explode and blind people.

Posted at 6:39 pm on Jul 5th, 2009 by Andrew Pollack

awesome! I work for a battery company and that little tool would be very useful to us, is there a way to make that guy mail it to us or sumthing??!?!?! please thanks bye!@#$%

Posted at 6:45 pm on Jul 5th, 2009 by digidev

wow. I could almost show this to my coworkers, if it weren’t for the stupid dreadlocks.

Posted at 7:29 pm on Jul 5th, 2009 by jeremiah

Hmm looks like the only thing the AVR is doing is generating a pulse… might be cheaper to use a smaller AVR with PWM or a pulse generator IC.

Posted at 7:42 pm on Jul 5th, 2009 by razorconcepts

@razorconcepts
or just a 555 timer IC and a few $0.005 passives ;)

Posted at 9:35 pm on Jul 5th, 2009 by eric

bah why use such toys when if you know what you are doing you can do this with such things as a dead mans cord or even a welder if you are really really good.

oh yeah going that route can be very dangerous and i do not suggest anyone try it, but it does work

Posted at 10:40 pm on Jul 5th, 2009 by h_2_o

@Andrew Pollack
well this is for dead batteries
i dont think they have much energy stored up lol

might have to make one of these tho
always happens to my 4wheeler

Posted at 11:15 pm on Jul 5th, 2009 by thomas

You stated 3 weeks but how much sulphate before you start? A little, a lot?

Posted at 12:20 am on Jul 6th, 2009 by grovenstien

prolly when it wont hold enough charge to turn the starter
ur better off using a dead car battery as core discount then trying to fix it unless u have alot of them

Posted at 12:42 am on Jul 6th, 2009 by thomas

@thomas

Wrong. This is for batteries with high internal resistance. That doesn’t imply that there isn’t potential energy sitting there ready to be unleashed as soon as conditions allow…

Posted at 2:00 am on Jul 6th, 2009 by draeath

Anyone know where I can get schematics?

Posted at 6:45 am on Jul 6th, 2009 by joe

@joe
there’s link to this project and there’s downloadable schematic. that green underlined text is link :)

Posted at 8:23 am on Jul 6th, 2009 by zake

@Andrew Pollack and @dreath: Personally, after all the recent stories of batteries bursting into flames, I always assume that a battery is capable of, at least, splitting and spraying it’s electrolytes around. The best bet might be to put the battery in a metal can with a loose lid (garbage can?) and make sure it’s in a reasonably ventilated area over the three week period you’re doing this. The metal should stop any flying electrolyte/battery components and by keeping the lid loose, and locating the can in a ventilated area, you should be able to deal with any fume build-up safely.

Posted at 9:35 am on Jul 6th, 2009 by colecoman1982

Actually battery maintenance is quite dangerous. sulfuric acid, which is where the sulfur crystals come from, is highly corrosive. You noticed he was in an open area, wearing gloves. Ideally, shorts and a t-shirt are not good clothing to wear when doing this, as a splatter or spill is likely to hit unprotected skin. Eye goggles at the very least, I would suggest splash shields instead. I never had a problem with discharge, but if you have ever seen a capacitor spot weld a motherboard then you should treat these things like that. They are capacitors in a literal sense. More danger from the acid though.

Posted at 10:42 am on Jul 6th, 2009 by greycode

Surely, three weeks of this thing chugging away, eating electricity, would negate any savings. Buying a new battery must be cheaper, what is its power consumption? Not to mention the $55 to ship it”!

Posted at 2:19 pm on Jul 6th, 2009 by Gerty

Define “high frequency”? I do pretty well with my homemade desulfator, which consists of full-bridge rectifier spitting out 120Hz half-wave, some resistors, and a regulator to bring the pulsing DC down to 14 volts. I’ve never seen a reputable citation saying that frequencies higher than that do anything worthwhile.

Posted at 3:21 pm on Jul 6th, 2009 by j9

Is there any way that this trivial task could be done with MIPS r10000 CPU or at least Pentium 4?

no, seriously, I want to know if someone ever used an cray supercomputer as a doorbell, or RFID tag?

I seen all kind of crap done by mcu’s, but this beats all of them.

Posted at 3:53 pm on Jul 9th, 2009 by rapid half-wave bursts

Hey is it possible that we attach the desulfator permenantly to the lead acid battery????

like with the UPS,auto battery etc etc??????
will it be good for the battery to attach it for along??????will it keep the battery fresh all the time?????or what???m bit confuse in it!bhaaaaaa

Posted at 3:42 am on Sep 4th, 2009 by Hasan

As Eliot Phillips works great im really impressed……..Well i need all of your suggestions about my above post…….as im a Manufacture of Lead Acid Battery and im thinking to attach the lead acid battery permenantly during manufacturing battery………and sell it …what you people says about it??????

Thanks

Posted at 3:49 am on Sep 4th, 2009 by Hasan