Diy portable 18650 tea maker

completelycharged

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Good way to test out battery packs... with stainless steel the main issue is the chromium compounds through electrolysis from the differential along the coil as they are very toxic.....

The 12V immersion unit will be good to see in action...
 

Riplash

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completelycharged said:
Good way to test out battery packs... with stainless steel the main issue is the chromium compounds through electrolysis from the differential along the coil as they are very toxic.....

The 12V immersion unit will be good to see in action...

Chromium poisoning through tea doesn't sound too good. I only need about 4.5" of stainless steel wire to get 0.1 ohm of resistance. That should get me near 1A per cell. So tonightI might make a flat heating coil,fasten it to a brick, cover it with layers of kapcon tapeand heat a small metal pot of water.

I am also looking at reusing some of the thermistors from the laptop packs and hooking them up to an Arduino and using that to measure and record temperature in the test battery pack. Eventually I want to be able to to measure battery pack temp, voltage, Amps, power, and send it to a computer.
 

Riplash

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I made some tea this afternoon, and I don't have any chromium poisoning. I ended making a burner out of a concrete tile, 20 inches of Stainless steel wire, Kapton tape, and used a 1 quart pot to cook the water.

The setup pulled about 32 to 33 amps from a 1s x 40p battery pack and I ran the pack from 5:15 till about 9:00 p.m. I didn't have any air blowing through the battery box, but the batteries only increased 20 degrees F. From 83 degrees F to 103 degrees.


Here is a picture of the Burner


image_fjipms.jpg


And here is a picture of the test setup:


image_vjluno.jpg


When this was running I went inside and took a thermistor off of a laptop battery pack, and made an Arduino Temperature meter. The test was over by the time I had all the bugs worked out. But I got it working and will save a lot of thermistors from the batteries Idisassemble.I will probably convert the breadboard to a prototype shield, or hardwire it. All the loose wires drive me nuts....


image_ndgcot.jpg


Cheers,
Ryan
 

completelycharged

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Where is the tea bag ? :p
 

Riplash

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Okay, Jason and myself have made tea, and it was awesome, but I am ready to move onto the next step... Cooking a potato, and/or making a french fry ( a chip for formal English typepersons). If I just put stainless steel coils in cooking oil (I will probably use canola oil) and run current through the coils will any toxic or bad chemical reactions take place? I shouldn't have any electrolysis take place since the oil is non polar. I think I will have to have two or more test cases. One for the amount of energy that I want to pull out of the battery pack to test.... I might have to add some mass or something to keep it cool and keep the oil from getting too hot. The second test case will be trying to keep the oil at the optimum temperature for the best French Fry. I can think about the test conditions now, but it will probably be half a week before I actually get to work on testing it.


Looking forward to your thoughts,
-Ryan
 

Korishan

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Using a piece of metal and then using induction will not leak any metals out. At least, unless it's an unstable metal to begin with. I would probably go with a piece of steel instead of a few coins. The coins may just move around to much themselves and not make much heat.

If you took a piece of 1/8" steel plate and put that in the oil, it should be heavy enough to stay put, and then generate the heat.

Altho, coins moving around in the oil would probably look neat :p
 

completelycharged

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There should be no electrolysis because the water molecules will have bond separation by the oil molecules, unless you end up with a lot of water in the oil or steam pockets with boil off.. avoid steam bubbles from passing over the coil as you then end up with potential for electrolysis of steam if the voltage differential on the coil is big enough......

Piece of wood, pit nails in and then zig-zag the wire between them to create a base. Weigh the wood down with metal - even distributed heating.

image_lsobzh.jpg


In the FAQ wiki :D a section could be on "cooking with cells" and then list all of the unconventional and conventional cooking projects powered by DIY and portable battery packs..


I bet both of those cups of tea were the really satisfying brews of achievement... the end result you can actually taste.
 
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