In message <005c01c3fa2c$092328b0$0402a8c0@xppro>
          John Ferrell <johnferrell@EARTHLINK.NET> wrote:

> I think that was the chip I encountered in an APC battery pack for my old
> Compaq 1237 Laptop.  It uses a NiMh pack.
I kinda guessed that :)

> The problem turned out to be
> getting the initial state of the battery to match what the chip expected.
That's the problem I've been having. I can get it to pick up that the battery
pack is totally kaputski, then it resets its registers and counts the charge.
What I don't get is why it never updates the LMD - this means that the "gas
gauge" display always displays around 80% when the battery is full. If LMD
was updating, the gas gauge would display 100% when the battery is full.
I guess I need to rig up a decent-sized battery pack. I've got four GP
"Industrial Rechargeable" (yes, the lime green ones) 150AAH AA-sized 1500mAh
batteries which shouldn't be too hard to build up into a pack. I've also
tracked down a 15W 0.1R resistor which should work quite well as a sense
resistor. It's bigger than one of the batteries! :-/

> I decided that one condition that should be expected was a battery that had
> shelf discharged. I removed the battery cells, cycled them a couple of times
> on a charger,
The catch: I don't have a charger that can fastcharge NiMHs. I've got one of
those black Made-In-China cheapie nicad chargers (branded "Calvin
Industrial", came from Maplin Electronics), but nothing that's specifically
for NiMHs. The fact that the GP batteries are tagged with no "nipple" really
doesn't help.

> discharged them, reinstalled in the pack charged it in the
> computer, ran it down with the computer, recharged and it worked. I stopped
> there!
:)
So the trick is to cycle the individual cells a few times, then run them
flat, hook them up to the Bq chip and then cycle them again while the Bq is
hooked up and monitoring the cells? Makes sense to me.
%DEITY, these chips are picky.

Thanks.
--
Phil.                              | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem@dsl.pipex.com              | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.dsl.pipex.com/  | 48xCD, ARCINv6c IDE, SCSI
... If it's not broke, let me take a crack at it.

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