Submerging AA batteries?

Discussion in 'The Projects Forum' started by tegguy, Oct 19, 2013.

  1. tegguy

    Thread Starter New Member

    Oct 19, 2013
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    So I need some advice..... I'm working on a project for the center pieces of my wedding using 4-5 LED's and a couple AA batteries. I was planning on using mineral oil to submerge them in but there is question about the effect of the mineral oil on the flowers. Would there be any harm in just submerging the AA batteries and LED's in plan tap water? Also would there be any harm in mixing the water with sprite?

    I don't want to use the LED's cubes I like the light output of these better.
     
  2. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I can see distilled water being OK, but anything introduced that may contain acid can cause conduction through the liquid.
    Max.
     
  3. #12

    Expert

    Nov 30, 2010
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    Mineral oil is safe enough for low voltage batteries. Several oils are used to cool transformers with a LOT more voltage. Just stick your ohm meter into the mineral oil and expect very low DC conduction (high resistance). I think it will be bad for the flowers, but it will take time for the flowers to object, probably hours.
     
  4. MaxHeadRoom

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    Jul 18, 2013
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    What about Veg oil such as Olive oil etc, test the effect on each?
    What is the reason for the oil anyway?
    Max.
     
  5. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Can't you just waterproof the batteries, e.g. by wrapping in cling film?
     
  6. tegguy

    Thread Starter New Member

    Oct 19, 2013
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    I could wrap the batteries in that but the exposed LEDs would be a problem and I can't wrap those. Flowers are currently sitting in mineral oil to see what they do. I'm worried about the flowers in an oil. We need to oil for a lighting effect
     
  7. tegguy

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    Oct 19, 2013
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    Would there be enough conduction to harm anything?
     
  8. MaxHeadRoom

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    I am not sure what is in Sprite, you would have to make a simple conclusive test!
    I have had simple high impedance input circuits conduct in tap water.
    Max.
     
  9. tegguy

    Thread Starter New Member

    Oct 19, 2013
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    Is there any harm of the batteries exploding or anything being fully submerged in tap water?
     
  10. MaxHeadRoom

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    No, if anything they will just be prone to possible discharge sooner than they would be in free air.
    It may be best to keep the + and - poles away from each other, and also use heat shrink as much as possible over the connections, another very good way of stopping the conduction is to use Dielectric grease, it is a bit messy, but effective.
    You can get it at any automotive store.
    Max.
     
  11. tegguy

    Thread Starter New Member

    Oct 19, 2013
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    We only need them to last 24 hours or so. Maybe I'll try to submerge my setup and see how long it lasts
     
  12. WBahn

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    Mar 31, 2012
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    I suspect that Sprite would increase the conductivity quite a bit.

    Why do the batteries need to be submerged? Is running a pair of wires (thin with suitably colored insulation) into the set up an option?

    Could you encase everything in a clear acrylic and put that down into the water?
     
  13. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    Just curious? Why Sprite? What is the lighting effect you are after?

    Encasing the batteries in clear acrylic also gave me the idea of encasing them in clear bathroom silicon caulk. Might be easier.
     
  14. #12

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    True. Faster, cheaper, easier. Just right for a very temporary job.
     
  15. Shagas

    Active Member

    May 13, 2013
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    You could laquer or even paint the exposed LED legs
     
  16. #12

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    Laquer: fingernail polish
     
  17. tegguy

    Thread Starter New Member

    Oct 19, 2013
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    The florist said sprite bubbles adhere to the sides of the flowers. I'm not sure if we are going to do this or not but basically we put the battery pack with attached LEDs in the bottom of a vase, fill it with round clear glass marbles, add water and it gives a cool light effect.

    Cost is a factor and need these to be as cheap as possible I have a ton of loose LEDs
     
  18. sirch2

    Well-Known Member

    Jan 21, 2013
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    I'd go with water and I think the LEDs would be fine for hours if not days in distilled and probably tap water, you need to keep the batteries dry though. I have seen a guy running mini-submarines in tap water with the motors running wet. Put the batteries in plastic tube and seal the ends with silicone sealer.
     
  19. tegguy

    Thread Starter New Member

    Oct 19, 2013
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    Is there a reason for the need to enclose the batteries but allow the leads to touch the water? I only need these to last about 24 hours
     
  20. WBahn

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    Mar 31, 2012
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    My guess is that the Sprite gives a lot of bubbles. Sparkling water might be an other option -- but don't know if it would be significantly less conducting.

    Clear caulk might work -- worth a trial, anyway. I suspect it might not be as clear as we think. But it's much easier to work with and you can just coat the leads and leave the lenses uncoated. Since it doesn't have to last forever, it's worth a shot.
     
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