trader_4
Sat, 03
Sep 2016 16:08:35 GMT in alt.home.repair, wrote:

On Saturday, September 3, 2016 at 11:14:04 AM UTC-4, Mr. Man-wai
Chang wrote:
On 3/09/16 22:57, trader_4 wrote:
... that I've seen in the news that blew up, I haven't seen one
where it was attributed to draining it too fast. Most of them
were when they were being *charged*.


What if you short-circuit it? Could it still do damage?


Sure, if you're dumb enough to do that and it's charged. But
again, that isn't the problem, that isn't what's happening with
any of these problem Lion batteries, it's not what's happening
with Samsung. They are burning up, exploding in normal use.

It's likely due to problems with the manufacturing process and/or
defective components within. The batteries can fail in fantastic ways
by being charged, discharged or just sitting idle, if the right
combination of internal failure takes place. Mostly, it's the
seperator that runs into problems. When it fails due to holes being
poked thru it by inferior construction materials that are uber tiny
in nature, your battery is literally, internally, shorting out. If
the organic solvent that's being used for electrolyte for some reason
damages/degrades the seperator, you've got yourself an internal short
circuit condition that can affect one or more cells.

As other cells are forced to join in, either by being shorted
themselves or just being heated by a failing cell near them, thermal
runaway begins to take hold. The organic solvent being used as an
electrolyte is turning into a gas due to the heat. A cell that's now
causing excessive heat can ignite it, inside the battery pack. If
that happens, you have a cascading thermal runaway issue and the
battery pack will go up in flames.

That's actually a rare event if you consider how many batteries of
this kind are made and used every day. Most of the time, the
batteries internal and external safeties will kick in and prevent the
fire aspect, although the battery is still going to be permaruined as
a result of the safety being enabled. It's a one shot deal.



--
MID:
Hmmm. I most certainly don't understand how I can access a copy of a
zip file but then not be able to unzip it so I can watch it. That
seems VERY clever!
http://al.howardknight.net/msgid.cgi?ID=145716711400