Cooking with second life 18650s and Stainless Steel wire is in progress....
I began work on the tea making process. I wound about 3 feet of stainless steel wire around an 18650 coil and that was about 1 ohm of resistance. I filled up a 1 quart (about 1 Litre) measuring cup full of water about 85 degrees (around 30 degrees Celcius). I calculated that it would take about 94 watt hours of energy if all the energy went into the water, and no water escaped. I have a cheap voltmeter/ammeter/watt hour meter that I planned to use. I hooked it up, and the wire began to get warm, but no display on the wattmeter. I looked at the directions and I needed about 6 or 7 volts to operate the meter. So I got out the very first pack I made a 4s 10p pack and hooked it up.
The jumper wires got toasty and I quadrupled up the jumper wires. The wattmeter came on so I zeroed it and took picture number 1:
It was about 85 degrees outside, and about 7:45 pm. The water heated up, and turned tea colored, and I probably separated some water molecules into H2 and O2 molecules. At about 8:30 or 90 Watt hours into the heating, Cell Bank 2 was very low about 3.1 Volts, and the rest were around 3.5 or so., So cell bank 2 in this pack is very weak. I soldered aligator clips to a tp4056 and put cell bank 2 on charge in order to get more energy out of the pack. Here is Image 2 about this time
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I let it run, and at 9:00, I put a plastic cover over the water to limit heat escape through evaporation. At the end the Voltage rapidly fell off, and the water was at 190 Degrees F.
I was able to get about 200 watt hours out of the pack, pulled about 12 to 13 Amps from the pack which is about 1.2 to 1.3 Amps per cell. It was about 80 degrees F outside, and the cells got to about 105 degrees F (40 ish degrees C). The water looked like Tea also, even though it was probably just Iron Oxide from the stainless Steel. Half of the coil was black. I will probably switch the polarity of the SS coil and run it until it heats up the water without visible discoloration, then I might actually make tea. I will make some current shunts, and get thermisters in order to test the 1sx40p pack. I will probably make a few different coils to pull 1 A per cell, 2A per cell, 3A per cell, and maybe 4A per cell. And then try to bake or fry a potato.
I never thought I would be so excited about cooking a single french fry or potato. But I can test all sorts of test equipment and ideas in the process.
-Cheers,
Ryan.