Submerging AA batteries?

WBahn

Joined Mar 31, 2012
29,979
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
Actually sounds rather interesting. I can see embedding various different LEDs more-or-less randomly in a pile of such marbles (maybe even some lightly colored ones, too) in an aquarium bowl as a mantle display (not talking about your wedding, here). Unless the water really adds something, could leave it dry. Or perhaps use mineral oil and use a fish tank aerator to introduce bubbles underneath the marbles.
 

Thread Starter

tegguy

Joined Oct 19, 2013
15
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.
I think i'm just going to try and dunk my sample pack unsealed into water and see what happens from what I'm hearing there isn't too much risk worst case the batteries don't last very long.

FYI flowers do not like mineral oil......
 

Bernard

Joined Aug 7, 2008
5,784
What color LEDs are you using, red ok for 2 AAs, white or blue will need 3 AAs. Guessing leakage around 5 mA, so about 300 hrs not counting LEDs. How are you connecting the batteries? Painting assembled ckt with clear nail polish might help.
I soldered 3 AA's together, 47Ω, & bright white LED then put them in a glass of Fresca. Dry they were pulling 26 mA, in Fresca 27 mA, without spaghetty or paint. With 2 silver electrodes , 2.6 sq cm ea, 7 cm seperation measured 3k Ω. See no reason that setup will nt work if bare connections are limited.
 

Thread Starter

tegguy

Joined Oct 19, 2013
15
Actually sounds rather interesting. I can see embedding various different LEDs more-or-less randomly in a pile of such marbles (maybe even some lightly colored ones, too) in an aquarium bowl as a mantle display (not talking about your wedding, here). Unless the water really adds something, could leave it dry. Or perhaps use mineral oil and use a fish tank aerator to introduce bubbles underneath the marbles.
It provides a really cool effect. The water really makes the light reflect and scatter more I'll post up a sample picture if I can later.
 

Thread Starter

tegguy

Joined Oct 19, 2013
15
What color LEDs are you using, red ok for 2 AAs, white or blue will need 3 AAs. Guessing leakage around 5 mA, so about 300 hrs not counting LEDs. How are you connecting the batteries? Painting assembled ckt with clear nail polish might help.
I soldered 3 AA's together, 47Ω, & bright white LED then put them in a glass of Fresca. Dry they were pulling 26 mA, in Fresca 27 mA, without spaghetty or paint. With 2 silver electrodes , 2.6 sq cm ea, 7 cm seperation measured 3k Ω. See no reason that setup will nt work if bare connections are limited.
I have blue LED's and I did a test and 4x LED's wires in parallel with the 2 AA batteries wires in series lasted 24hours+. I'm contemplating getting a battery pack with a switch on it and then trying to seal as much as possible but I want to make sure worst case scenario (everything gets wet) will work. Granted my testing was in Mineral Oil.
 

djsfantasi

Joined Apr 11, 2010
9,156
Just had another idea simpler than clear caulk and similar to nail polish. Home Depot and WalMart both carry a product to coat tool handles. Plasti-Dip. It's under $10. Can be painted on all exposed wires or terminals. It will remain flexible while wiring and placing your lighting system.
 

WBahn

Joined Mar 31, 2012
29,979
I didn't know Plasti-Dip now came in clear. I doubt it is as optically clear as he probably needs, but worth a try since you can certainly use the rest of the Plasti-Dip for other useful things.
 

WBahn

Joined Mar 31, 2012
29,979
I think i'm just going to try and dunk my sample pack unsealed into water and see what happens from what I'm hearing there isn't too much risk worst case the batteries don't last very long.

FYI flowers do not like mineral oil......
Sparkling water isn't the same thing as mineral oil. It's basically carbonated water -- the same thing used in Sprite and all other carbonated beverages. But it doesn't have the sugar and other things dissolved in it.
 

WBahn

Joined Mar 31, 2012
29,979
I think i'm just going to try and dunk my sample pack unsealed into water and see what happens from what I'm hearing there isn't too much risk worst case the batteries don't last very long.
Oh, there's no "risk" in terms of anything safety related (as long as you don't drink the Sprite afterward -- and even that would be unlikely to cause harm). Definitely give it a try. If it's good enough, then it's good enough. Mark that item on the wedding list done and move on.
 

wayneh

Joined Sep 9, 2010
17,496
Sugar alone would not be terribly conductive - it doesn't ionize - but any carbonation means carbonic acid in solution and thus higher conductivity. The citric acid in most fruity sodas (like Sprite) would add a lot more.

So open conductors might survive a while in clean water or oil, but not long in fizzy water and even less in a typical sweet soda.

Don't forget that any oil will lay on top the water.
 

WBahn

Joined Mar 31, 2012
29,979
Sugar alone would not be terribly conductive - it doesn't ionize - but any carbonation means carbonic acid in solution and thus higher conductivity. The citric acid in most fruity sodas (like Sprite) would add a lot more.

So open conductors might survive a while in clean water or oil, but not long in fizzy water and even less in a typical sweet soda.

Don't forget that any oil will lay on top the water.
Didn't know that sugar wouldn't make it conductive -- definitely as assumption on my part. Knew that the carbonation would, but figured that's the price of admission in this case.

Is it true that *any* oil will float on water? I seem to recall that some of the heavier crude oils at a density greater than water (or at least fresh water). I don't see any particular reason why oils can't be made that are significantly denser than water.
 

Thread Starter

tegguy

Joined Oct 19, 2013
15
Well the experiment has started 2 AA batteries and 4-5 LED's (Blue) currently .01mA and .02 Volts across the water. This is using straight tap water. I had a weird problem where it almost looked like there was smoke coming off the LED cause there were streak lines up the water but I think that might be residue mineral oil leaving the surface. I dumped the water and refilled it and so far nothing bad.

Any guesses on if I'll have problems and how long the setup will last? (currently running on a set of batteries that powered this setup for 24-36 hours once before)
 

MaxHeadRoom

Joined Jul 18, 2013
28,619
A sign of simple electrolysis, I cured the effect to a great degree by the smear of dielectric grease, it is invisible under water.
Max.
 

THE_RB

Joined Feb 11, 2008
5,438
Spray the wiring with clear lacquer before immersing?

There's no need for the liquid to touch anything metal or conductive, just use a couple of thick coats of clear on the electricals.
 

WBahn

Joined Mar 31, 2012
29,979
If I remember correctly no harm with this if left alone core t? I'll try dielectric possibly
I have no idea what "core t" is supposed to mean, so I don't know if I'm interpretting your question correctly.

There will probably be no harm at the voltages you are working with. Depending on what is in the water, you may be releasing hydrogen and oxygen or you might be releasing come thing else. For instance, if you take water and put salt in it, you will generally release chlorine gas rather than oxygen. But even if that where the case here, it is unlikely that you could produce it in sufficient quantity or at a sufficient rate to cause a problem.

But don't take that as professional advice.
 
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