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

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287 points jonbruner | 2 comments | 24 Sep 25 19:29 UTC | HN request time: 0s | source
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bahmboo ◴[26 Sep 25 23:58 UTC] No.45392244[source]▶
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.

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bahmboo ◴[27 Sep 25 03:42 UTC] No.45393069[source]▶
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.
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eth0up ◴[27 Sep 25 04:08 UTC] No.45393150[source]▶
Molicell?

I have one in 21700 and it seems a great battery so far. Otherwise I'm a Panasonic guy.

I ask because it sits on my forehead, inside a headlamp. Having my hands tied, addressing a problem quickly might be difficult. And them rascals get toasty fast when they ignite.

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1. jdietrich ◴[27 Sep 25 10:22 UTC] No.45394578{4}[source]▶
Molicel is top tier - their P50B is the best 21700 cell available on the open market. Eve, BAK and Ampace also make some really good stuff, although they can't match the performance of Molicel.
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2. Adachi91 ◴[27 Sep 25 16:39 UTC] No.45397328[source]▶
I came to the same conclusion when upgrading from 18650s to 21700s, I spent a long time trying to weed out the poorly binned rewards, and the minefield of lithium batteries. They weren't cheap but have been happy with their performance.

There are a lot of people out there that see 18650 or 21700 and think a lithium ion battery is a lithium ion battery and they're all the same (i.e. trying to pull 20 amps from a 2 amp peak battery). I miss one of the father's of liion battery education, Mooch (from ecigarettes forum) who had a whole methodology of testing, and educating people.