Hi Guys....

As part of my current project recycling old computers.... for charity, I
have come accross a few old battery packs, left over from lap tops...

Thinking about what someone had said about there usually only being a few
bad cells in a pack, I cracked one open, to take a look inside.

Sure enough, there were a few bad cells, and a few extra components I
hadn't expected to find.

Taking apart a second, different type of battery pack, has added to my
confusion, and just increased the number of questions I have....

I figure one old 10 hour laptop battery should have more than enough power
for  a PIC for quite a while, so I was looking at the design, in order to
figure out how to borrow parts of it for my PIC'N.

Anyways, I figure the radial lead unit that looks like a cap, with a
pointed cap, is some sort of temperature cut-out element that breaks the
circuit if it overheats, its labeled micro-temp, so this seems likely. and
I figure the square cross-section but long can, with the Isuzu label on
it, is probably an auto-rated breaker to cut the circuit if it goes
over-amps....

But what I can't figure out, is why the only two cells that have anything
wrong with them are the ones these two circuit elements are connected to?

The battery pack is supposedly a NI-MH type, rated at 12V and 2.2A for
10hrs. it has 10 "Sanyo TWICELLS" rated at 1.2V each.

But a similar phone pack, using the same Ni-MH technology, has cells rated
at .6v each.... Am I right in assuming they are hiding two cells in the
TWICELL cylinders? and that the base voltage of a Ni-MH cell is .6V?

Or are the phone cells simply under-charged?

                                GREY

GRAEME SMITH                         email: grysmith@freenet.edmonton.ab.ca
YMCA Edmonton

Address has changed with little warning!
(I moved across the hall! :) )

Email will remain constant... at least for now.