Special thanks to Ross for sending some extremely detailed images of reverse charge failure of a lithium cell. He deliberately reverse charged a cell with force, disassembled it and then photographed it with a scanning electron microscope so we could all see the actual physical internal failure.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
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This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
This is probably not a SEM image, more likely from a digital microscope
I have access to a scanning electron microscope. Those are cool right?
Cool to see it instead of just theory
Very interesting and informative. Thank you.
Fantastic & shared – how did I miss this one!
Very cool info! Thanks for sharing this with us. I tend to agree with you and have never tried any "brute force" approaches to fixing lithium ion cells. Now I see that was very likely a wise decision!
Thank you Ross. Quite educational indeed. And thanks to our favorite Info Bear for presenting it to us.
Aren't they rechargeable? I don't get the reverse charge part being very damaging. Thanks.
I am a professional atomic force/scanning probe microscopist and this is really damn cool. I'm pretty tempted to give this a try. I can probably measure some degree of electrical conductance through these individual pores/domains as well.
Knowing what happens during this type of failure actually makes repairs possible
Did anyone else laugh at "He doesn't actually own an electron microscope"?
Does rosses SEM require gold plating of objects?
I’m getting a flashback to Photonic’s lithium disaster with a screwdriver. “I only poked it!”
About 35 years ago when I was first working as an electronics technician we used to rejuvenate NiCad batteries that had a fairly regular similar shorting characteristic, apparently forming whiskers of nickel through the electrolyte. We had a giant stack of high voltage capacitors wired in parallel which we would charge up to 50V and then zap them with an essentially instantaneous spike of current and were usually able to resuscitate them to get another year or so out of the batteries. In that case the batteries were weather-sealed units for a specific model of handheld radio and they were frightfully expensive so this particular trick saved many times more than my annual salary each year.