On Wed, 15 Nov 2017 19:32:50 -0800, Jeff Liebermann wrote:

On Wed, 15 Nov 2017 18:52:06 -0000, "Ian Field"
wrote:



"Jeff Liebermann" wrote in message
. ..
On Tue, 14 Nov 2017 19:22:17 -0000, "Ian Field"
wrote:

Just curious about the failure mode - the cells really weren't worked
that hard.

Here's how to fix it: https://www.youtube.com/watch?v=IhUtKvCV6fs
https://www.youtube.com/watch?v=1w3Tv1Jg0ps

Every day is a school day.

That's another variation on my "Learn by Destroying". If you haven't
destroyed it, you don't understand it. My skool education was very much
like that. I would break something, and then take it apart to see how
it works. The skool would frown upon me taking apart something that was
still working, but offered little resistance if I took apart something
that was broken.

I might have to rummage those cells out of the bin and do an autopsy -
but conscious enough of potential hazards to not bother re using them
though.

Bin? Don't you have a local recycling facility that takes batteries?

Plenty replacements to hand, I just assembled another battery pack - but
that seems to answer my question; what happened.

It might answer what happened, but not why. I've had brand new battery
packs, assembled by a reputable and experienced rebuilder, trip the
protector for no obvious reason. I recently had one go open circuit
during charging, which might offer a clue.

If the battery has a protection circuit built in, you can tell by the dark
band at the negative terminal and a strip up the side to
the positive it will trip at something under 3 volts and refuse a charge
for safety sake.

You can put a very low current limited charge into the to get
them up to around 3.2 - 3.4 volts then and only then will
a lithium battery charger ( a proper one) attempt to charge it.