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I had to come back because the paper doesn't specify the chemistry of the laptop battery; you can't use this as evidence to support anything other than caution around Li-ion batteries and cells.

And, more alarmingly, the part you omitted or glossed over: their plausible explanation for the lower HF detection (which, again, would depend wholly on the chemistry of the cells):

> the laptop cells exploded with liquid splashed on the walls in the equipment

Whoops.

Don't mess with these things unless you know how they can be safely tested, safely charged, and safely monitored. Li-ion protection failures (of various modes) were responsible for the Boeing Dreamliner fleet being grounded, Tesla refitting their battery packs (road debris caused a fire when it pierced a Li-ion cell), hoverboards being recalled, millions of dell laptops recalled after battery fires, and more recently, the Samsung Galaxy Note 7.

So, yeah. Safely tested, charged and operated is the key, and I wouldn't want to take that responsibility for a pack with as many batteries (and who knows which ones have their own standalone protection circuit in the cap) as in TFA.



And, more alarmingly, the part you omitted or glossed over: their plausible explanation for the lower HF detection (which, again, would depend wholly on the chemistry of the cells):

> the laptop cells exploded with liquid splashed on the walls in the equipment

The less electrolyte that gets burnt, the less HF generated, which I hope you agree is a good thing.

and more recently, the Samsung Galaxy Note 7.

How many actually burned? It's a very tiny fraction. Manufacturers recall precisely to avoid the sort of hysteria that statements like yours generate, and it's not any indication of impending doom. The aviation industry is particularly risk-averse, so it's not surprising. But I don't think the risk is very high compared to a lot of other things in our lives, especially when you consider all the lion cells out there of questionable quality in use and yet behaving themselves. China has taken the lead in making 18650s and other lion cells almost as easily available as alkalines, but reports of fires do not appear to have increased anywhere near in a direct proportion to that. (Reports of cells failing to meet capacity specs, on the other hand...)

By all means handle with care (as you should with any energy source), but lion cells are not lethal weapons that will instantly kill you at the slightest provocation.


Are you serious, or trolling? Weird question to ask outright, but I wanted to save time.

Regarding the battery exploding. Yeah, I'd agree that ... no! No, I don't agree at all! First, it exploded, so there's that. A cell in the middle of a multi-cell pack has nowhere to go. Second, it invalidated the experiment; they don't know how much HF would've been released in a real world scenario where the compressed cylinder of reactive metals and gasses is not free to "rapidly disassemble" into the air.

Now, moving on to Samsung's recall. How many failed? Sure, a small fraction. Do you know if yours will fail? How could you possibly know? Wait, I had something for this... oh, yeah. Safely test each cell.

Samsung didn't have that capability, their battery vendor didn't have enough engineers for all those house calls. You don't have that capability (you seem quite cavalier about the whole endeavor, so I'm guessing there). So, yes, since they can't know without testing, they recalled them all. What do you suppose they'll do then?

Probably, get together with the vendor, and test them.

Please stop suggesting to other readers that these things are perfectly safe when you know they're not. They're not tiny little bombs waiting to go off if you sneeze near one, but anyone using untested lithium-ion cells/batteries in untested configurations without a controller on each cell should be discouraged. We don't need a new category of Darwin award winners.




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