At the risk of looking like a stereotypical noob, this thread has always creeped me out. More specifically, hydrofluoric acid creeps me out.
I took semiconductor classes at Uni, and the labs were some of the most interesting I've ever had. We did some very basic processing to create some of the most fundamental semiconductor structures (transistors, etc.) on Silicon, which involved the usual process; growing a silicon oxide layer, applying resist, photolithography, and then etching. After you have your pattern defined by a layer of resist, etching of the underlying SiO2 layer is done with hydrofluoric acid, and everything that was drummed into us about HF game me the willies. Undergrads never handled the concentrated stuff, but even the diluted stuff we used was very, very scary.
Not only is it often immediately painless, but fluoride ions permate skin rather easily, and has an affinity for calcium, i.e. your bones. Worse, however, is the way that it also forms various soluble salts that not only end up in the bloodstream, but which eventually disassociate again resulting in more fluoride mayhem all over the place away from the initial exposure site. It really is unimaginably horrible stuff, and my skin used to crawl when I was anywhere near it.
I know it's been stated already, but it's probably worth hammering home that
all lithium ion batteries are an HF risk when they're opened. It's not just the primaries; rechargeables are also a risk, (albeit a low one with quality cells).
If you look at the MSDS sheet for any battery from any manufacturer, they don't go into too much detail on a cell's composition; certain parts of the breakdown of ingredients by weight are often listed as confidential, as most don't want to give away any proprietary secrets on electrolytes, etc. However, they do invariably state that one possible side effect of an opened cell is a release of hydrogen fluoride, which becomes hydrofluoric acid in moisture.
For example, Home Depot (of all places) has a copy of the MSDS for an older
Samsung INR 18650. Page 2 gives a percentage breakdown of stuff by weight, and nothing in the datasheet looks particularly concerning, up until the head of page 4:
It really does make me wonder if most of the folks that open these cells up for youtube videos, etc. really know the risk they're taking...
The other thing I've had stuck in my mind for well over a decade now is how differently LiIon cells are viewed. In a past life, I worked at Motorola PCS, and amongst the array of things I worked on, I was involved in the handset software that looked after battery charging on the GSM side of the business. When the transition to lithium ion occurred for mass-market products, the initial prevailing wisdom was that the cells were only really a risk when charging, and they were generally safe otherwise. As a result, the company put effort into the battery packs and handsets both to attempt to prevent charging counterfeit batteries and to allow the legal side of Mot. to go after counterfeiters (though the results weren't massively successful). It wasn't until later when there were millions of phones out in the wild that the first reports of venting and combustion started coming in. Thankfully, the vast majority of the cases I heard of were with 3rd-party batteries, many of which had either non-existent or ineffective safety circuitry in the battery pack. There were some Mot. batteries that went up, the majority of which were angered badly by being crushed, etc.
Anyway, I've lurked for years, and this is one of the threads I always told myself I'd post to if I ever registered and it was still active. I know it's some 4 years late, but I've always been massively sorry to hear that you were hurt, JNieporte.
