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Make a Lithium Thionyl Chloride Battery

video Make a Lithium Thionyl Chloride Battery
How to make a Lithium Thionyl Chloride Battery capable of generating 2.8v with enough current to power a LED.

Warning: Thionyl Chloride is EXTREMELY toxic and this experiment must be performed in a fumehood by an experienced chemist with proper safety precautions.

Lithium thionyl chloride batteries offer excellent shelf life (sometimes over a decade) and energy density. Their main drawback is they are not rechargeable but for low power applications like memory backup they are extremely useful. At very low power levels, they can outlast the device they are installed in, making the recharge issue a non-issue.

As seen in this experiment, they are also extremely simple to make.

A solution of lithium tetrachloroaluminate in thionyl chloride serves as the electrolyte and the lithium and carbon rods are simply inserted in. The cell can produce up to 3.5volts depending on the purity and quality of the components. Our cell in the video used waste chemicals we had leftover around the lab so the voltage is not that high. But it did produce enough power to light a small light emitting a diode.

Commercial cells use lithium foil and spongy carbon for greater current but the concept is still the same.

If you like this video, check out our others at http://www.youtube.com/NurdRage
llanyort2 years ago
how toxic are these batteries after usage ? how would i dispose of these batteries once depleted ? could i render this battery chemically inert ?
lemonie5 years ago
Yea thionyl! One of my favorites, I'm sure I "Swerned" stuff with this... L
NurdRage (author)  lemonie5 years ago
Swern Oxidation? sure that was thionyl? i think oxalyl chloride is for swern. I could be wrong though.
You're right, that's why I used "" - it's a variant. As I remember I sucked all the nasties down the sink with a water-pump, but Durham was like that... We also used to press our own sodium-wire - ever done that? L
NurdRage (author)  lemonie5 years ago
ah yeah.. sodium wire, never had to press it, just comes like that in the bottle if ordered that way. :)
Ah, but this was fresh, they seemed to think pressing it into the bottles of ethers would add dryness value, but I was never completely convinced as the stuff was pretty dry to start with and the stills didn't seem to last that much longer.

L
NurdRage (author)  lemonie5 years ago
if i need fresh stuff i just took the chunks of sodium and cut them up in the glove box. fresh surface, did awesome drying.
Aye, I'm sure the fresh wire is great too. Had a few fires when the younger ones were let loose with K... L
NurdRage (author)  lemonie5 years ago
Sodium presses are still sold so obviously someone out there wants the wires. For those without gloveboxes i suppose wire is the way to go :)
You do get a high surface-area to volume, and if you don't mind pressing it, more surface-area quicker. But if the ether's fairly dry, and you're going to dry it in a still anyway, and then have to get rid of the sodium-wire the value is questionable.... L
Biopyro5 years ago
What are the half reactions at the electrodes? Good explanation about it otherwise :)
NurdRage (author)  Biopyro5 years ago
Li --> Li+ and e- 2SOCl2 + 4e- --> S + SO2 + 4Cl-
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