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Thermistor
Mikey writes -

I recently ordered a $37 battery desulfator kit. It looks like a pretty simple device that sends pulses to lead acid batteries to help clean the battery plates. There are many success stories on the net about resuscitating essentially “dead” lead acid batteries. Since we have two electric vehicles and live off grid we have a lot of motivation to take care of our batteries. I’ve seen kits that sell for hundreds of dollars, but this 555 based kit seems to kick out a lot more juice than the fancy ones with wimpy solar panels.

Phillip Torrone

Editor at large – Make magazine. Creative director – Adafruit Industries, contributing editor – Popular Science. Previously: Founded – Hack-a-Day, how-to editor – Engadget, Director of product development – Fallon Worldwide, Technology Director – Braincraft.


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Comments

  1. just me again says:

    Yum yum Spam for a worthless product.

    1. Tigg says:

      59
      Batteries are very dangerous. They can explode if mishandled and while charging they give off hydrogen gas. Be very careful.
      A battery expert we met through our work installing renewable energy systems explained the process of reviving these batteries thoroughly so we set to work to do just that.
      It was a bit of a scary process at first and required two people to achieve success, but we soon worked out a process that was finally fairly safe.
      OK, SO WHAT IS A DESULFATOR?
      WHY ARE BATTERIES SULFATED?
      It is a safe bet that about 80% of all „dead‟ batteries are merely sulfated according my battery expert friends.
      Most batteries are made up of plates inside, that when left in an undercharged state become sulfated. That means that they develop a layer of sulfate crystals on the surface of the plates.
      After years of hard use, as in the case of the large industrial batteries we are talking about here, there are only two ways to remove the sulfate crystals from the batteries.
      You could take the batteries apart and clean the plates. This is what my professional battery builder friends do, but it is very dangerous and requires a special setup in your shop.
      A much safer way they explained was to build a desulfator. This is basically an electronic device that does the „shake, rattle and roll‟ at the plate level, without opening up the battery. This is Much safer, although still dangerous.
      Don‟t do this in the house, only in your shop environment.

  2. Phillip Torrone says:

    @just me again – how is this spam?

  3. gunterhausfrau says:

    Don’t know either way, so please educate. Why do you think this is snake oil? I’m nearing the end of an electric motorcycle build, so if it does do some good, might be worth it, but if it is more magnets on the fuel line…

  4. jammit says:

    I’ve heard about pulse desulfation, or resonant desulfation. I think I remember reading somewhere that NASA was looking into this (I couldn’t find any references unfortunately). There are a lot of sites out there where people have built and tried their own desulfators with pretty good results. Even I would be suspicious about such claims, but a lot of these sites aren’t selling anything and supply their schematics for free. The basic idea is this. If you try to charge a lead acid battery with a voltage above 14V, electrolysis and heat causes the water in the electrolyte to split into separate H2 and O molecules. The sulfite left behind coats the plates like an insulator. Simply adding more water, more acid, or dumping the fluid and replacing doesn’t remove the insulating material. If you briefly pulse the voltage to way above the charging voltage, due to the inductive and capacitive effects of the battery you get a high frequency ringing effect. This is assumed to cause the sulfate to separate from the plates and rejoin the water to rebuild the acid. The high voltage pulse is supposed to be short enough and repitition is slow enough that the battery or electrolyte doesn’t have time to heat up or electrolyse into H2 and O.

  5. jammit says:

    I’ve heard about pulse desulfation, or resonant desulfation. I think I remember reading somewhere that NASA was looking into this (I couldn’t find any references unfortunately). There are a lot of sites out there where people have built and tried their own desulfators with pretty good results. Even I would be suspicious about such claims, but a lot of these sites aren’t selling anything and supply their schematics for free. The basic idea is this. If you try to charge a lead acid battery with a voltage above 14V, electrolysis and heat causes the water in the electrolyte to split into separate H2 and O molecules. The sulfite left behind coats the plates like an insulator. Simply adding more water, more acid, or dumping the fluid and replacing doesn’t remove the insulating material. If you briefly pulse the voltage to way above the charging voltage, due to the inductive and capacitive effects of the battery you get a high frequency ringing effect. This is assumed to cause the sulfate to separate from the plates and rejoin the water to rebuild the acid. The high voltage pulse is supposed to be short enough and repitition is slow enough that the battery or electrolyte doesn’t have time to heat up or electrolyse into H2 and O.

    ps. Is anybody else having difficulty trying to add comments?

  6. jammit says:

    Ugh. Sorry for the double post. When I tried to post the first comment I was sent to a page saying it failed, so I posted again. Dear mod, please delete this post and my second one.

  7. william lai says:

    desulfators are not scams as far as I can tell. This is the original article from Home Power magazine that started the desulfator hacking scene: http://windpower.fleettrikes.com/desulfator.pdf.

    The site listed that sells the kit is pretty commonly accepted as one of the best resources online for the subject.

  8. daliumong says:

    so have you assembled and tried the kit yet?
    i’m getting frustrated with my batteries dying on me