Picking up free lithium cells off the street and making them safe for use

Re:Picking up free lithium cells off the street and making t... by UkrainianJew on Sunday July 17, 2022 @03:46PM (#32130488)

Sadly, this is not very practical. A lithium cell in itself is a chemical time bomb: if it gets mechanically damaged or short-circuited, it has enough oomph to burn your device, skin or house. For factory-produced battery packs this effect is mitigated by having protective circuits that monitor charge level, temperature and a bunch of other parameters, cutting off the power if the cell is deemed too dangerous. But once you take a random lithium cell off the street and try to revitalize it, you are opening a can of worms: depending on how it was used, it might be full of dendrites [0], ready to cause a fiery short-circuit a few charges after. It might have structural damage due to gas buildup, or someone literally stepping on it. It could have been under direct sunlight for longer than it should, and so on.

It's fine to tinker around with it for your own experiments, but you don't want to ship it to anybody who's not going to be using it in a fireproof lab wearing eye protection.

A better idea would be to find a way to properly recycle the raw materials (i.e. extract the lithium from a dead cell), but that could be several orders of magnitude more challenging.

[0] https://www.batterypoweronline.com/news/a-look-inside-your-b...

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Re:Picking up free lithium cells off the street and making t... by GekkePrutser on Sunday July 17, 2022 @08:22PM (#32133052)

> But once you take a random lithium cell off the street and try to revitalize it, you are opening a can of worms: depending on how it was used, it might be full of dendrites [0], ready to cause a fiery short-circuit a few charges after. It might have structural damage due to gas buildup, or someone literally stepping on it. It could have been under direct sunlight for longer than it should, and so on.

Yeah exactly what I was thinking.. I'm sure the cells used in these disposable devices weren't exactly the cream of the crop in manufacturing either. Probably cells that didn't pass QC or something.

It's pretty risky messing around with them like that.

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Re:Picking up free lithium cells off the street and making t... by mrguyorama on Monday July 18, 2022 @02:49PM (#32141930)

On the contrary, I bet these cells are perfectly good cells (initially, after sitting on the side of the road they should definitely be considered dangerous). Remember that "a completely functional lithium battery pack, sometimes with charging and protection circuitry" is sold pre-charged as a "top up" pack for mobile phones and meant to be thrown away after.

Lithium batteries are absurdly cheap, and it's not too expensive to buy essentially off the shelf, rated capacity and lifetime cells in order to be reasonably sure 99% of your products last for 99% of their rated puffs.

If your disposable vape doesn't produce as much as competitors because you cheaped out on your lithium cell procurement, your competitor will happily scoop up that business as word of mouth spreads.

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Re:Picking up free lithium cells off the street and making t... by wffurr on Sunday July 17, 2022 @06:30PM (#32132112)

The deposit can fund the materials recycling and encourage a take back program.

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