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12 V Battery Conversion to HHO Generator

  1. Sep 25, 2008 #1
    I'm trying to convert an old 12 Volt car battery into an HHO generator. I want to achieve electrolysis of water using a dead battery as the vessel. A battery seems to have all of the necessary components: water tight case, electrodes, connections, and vent holes.

    I've witnessed other devices that achieve electrolysis (using titanium and stainless electrodes and a little baking soda) and then hold a small charge...so I figured "why build a battery...why not use a battery?

    Unlike everyone else doing this, I'm not trying to fuel a motor or improve gas mileage. Instead, I want to generate a small quantity of HHO on demand, run it through a 1/8 plastic tube and try to achieve/test a small flame with a very clean burn (ultimately for use in a very light manufacturing process).
  2. jcsd
  3. Sep 25, 2008 #2
    You want to generate water with a battery?
  4. Sep 25, 2008 #3
    No, I want to use the battery to separate the water into hydrogen and oxygen.
  5. Sep 25, 2008 #4
    I want to add current to the battery to achieve electrolysis in the cells and capture the gas to a tube.
  6. Sep 25, 2008 #5
    I would read this before you blow something up and/or scatter acid in someone's face.


    The evolution of gas is an explosive mixure of H2 and O2. If you ignite the end of a tube it will follow back to the battery igniting the cavity of H2 and O2 remaining within the battery case.
    Last edited by a moderator: Apr 23, 2017
  7. Sep 25, 2008 #6
    I should have offered more details. First, I drained the battery of acid and neutralized with a baking soda and water solution...and rinsed several times. Next, I refilled with tap water and added a small amount of baking soda to each cell. Now I'm trying to decide if it would be better to reverse the polarity or connect normally to a power source...battery charger...to achieve the reaction?
  8. Sep 25, 2008 #7
    Look, normally, you have the plates separted to generate gases. The gasses of each plate should not mix. As you can expect, one will be oxidizing and one a reducing--together they explode when ignited.

    You need to keep your gases separate unless a gas bomb is what you're after.
  9. Sep 25, 2008 #8
    The battery will be full of water and a spoon of baking soda. The gas will be captured by 6 tubes and travel into a plastic cylinder full of plain water to "bubble". The rising gas will be exhausted out of a 1/8 tube (or smaller if necessary) and then ignited. A gas bomb is definitely not the plan.
  10. Sep 25, 2008 #9
    I thought the individual cells and plates in the battery would be ideal.
  11. Sep 25, 2008 #10
    In each cell of a lead acid battery, there are several interleaved plates.
  12. Sep 26, 2008 #11
    I'm not really understanding how your going to be capturing the gas from the vents in the battery. The gas forms at the electrodes and that's where it needs to be captured. Just going and letting the gases mix then collecting it isn't a very good idea.
  13. Sep 26, 2008 #12
    How much H do you want and what for?

    I filled a balloon once.
  14. Sep 26, 2008 #13
    This is a work in progress.

    Yesterday, I drilled holes through all 6 battery caps and inserted hoses...tight fit. These 6 hoses are running into a closed cylinder containing water. The gas will bubble into the water and rise to the top...hopefully create a little pressure...a filled balloon is encouraging...and be vented to a single 1/8 hose at the cap. I'm looking for a steel tip for the 1/8 hose...where I'll ignite a small flame.

    The issue I want to discuss is the polarity of the connection...I drained the battery completely...it won't hold a charge. Should I connect the battery charger normally or reverse the poles? Would a reversed polarity create a better reaction? Also, (safety is an issue here) is there a better alternative to the baking soda to achieve electrolysis?
  15. Sep 26, 2008 #14
    I blew up a large balloon but not with electrolysis....Caustic Soda and Aluminium chippings in a glass bottle. Just put the neck of the balloon over the bottle.

    Dangerous stuff.
  16. Sep 26, 2008 #15
    Way too dangerous! I want to achieve electrolysis using a battery...drained of acid and refilled with tap water and either baking soda or (I don't know what...it's part of my question).
  17. Sep 26, 2008 #16
    You're not listening. The plates are in each cell are interleaved. Opposites plates are in each cell in close proximity. You can't hope to separate the gases with this arrangement.

    You'd have to open the battery and separate the plates.

    If you are going to persue in generating explosive mixtures in a fragmentary glass container, complete with a fuse hole, at least wear something over your eyes and face. It makes it easier for the surgeons.
  18. Sep 26, 2008 #17


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    Staff: Mentor

    ....and an electronic ignition source!
  19. Sep 26, 2008 #18
    I thought the interleaved design would be ideal...lots of surface area.

    By the way, the "cylinder" is a very lightweight plastic shampoo bottle filled nearly to the top with water...I don't have any kind of death/disfigurement wish.

    The power supply is a battery charger...located 10' away.
  20. Sep 26, 2008 #19
    The ignition source is a candle...located about 10' away in the other direction.
  21. Dec 26, 2008 #20
    Hy WhoWee

    I am Jorge from Chile..Have you been able to use old car battery as a HHO Unit?

    Please feedback me on your experience, by logic it should work

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