CT scans of 1k lithium-ion batteries show quality risks in inexpensive cells

Seems like a good time to highlight this video from Grin Technologies and their experience with ebikes over the years.

https://www.youtube.com/watch?v=j92Gt4VviSQ

Summary Statement: He summarizes the results of the "sabotaging" attempts by saying, "we just couldn't for the life of ourselves get a nonprotected modern lithium battery to do anything" [02:40:27], in terms of causing a fire. (referring to 18650s)

There are certainly problems out there with cells but it was a surprising statement from someone with a ton of real-world experience. Also they are a very conscientious company so they don't deal with dodgy stuff if they can avoid it.

It's a long video but one takeaway is to only use cells from the top manufacturers: Samsung, Panasonic, LG and Sony. They are amazingly safe.

Unfortunately, for products with batteries in non-standard form factors, we rarely have a choice of a manufacturer. For example, with home robot vacuums, we can only hope that brands will use top quality cells, but the information what cells are used is not even available to the customer. My Neato vacuum still runs great, but now that the company is out of business, my only battery replacement options are from no-name brands, with zero visibility of what cells are used internally.

You also have the option of building your own battery pack for these, or to disassemble an existing pack and replacing the cells. How difficult that is depends on the manufacturer, but from a quick look at the Neato packs I see it looks relatively trivial.

I'm in the process of replacing the battery in my old robot vacuum right now, and for the amount of time spent doing that, I could buy a whole new vacuum. It's a pity, because the battery itself can be replaced just by plugging it in, but all the batteries I could find were AliExpress fakes, so my two options are either "more e-waste" or "spend $500 in time doing it myself".