Hello Bob.

I was in similar problem with my notebook batteries, (IBM thinkpad) they are
LiIon too, and the same problem, in my case the problem was that I buy the
computer (second hand) and the previous owner almost never used the
batteries (2 complete packs) so they are with 0 volts when i measure the
voltage.
when i load them into the notebook for charge, the charger says short circuit
which i realize true when measure with my ohmeter.

So, due to the high cost of these (around 200 U$S in my country), i decide
to do somethink crazy:
setting up the laboratory power supply at 14V and limiting it to 2 Amp.
(the battery is 7.5 V 4000 mah LiIon), I apply pulses of short duration
(100ms about, 1 pulse per second aproximately), that was for the time of
about 3 minutes until I saw that the current started to drop to 1 Amp. then
load the battery into the charger and.... voila!! It Works!!!!!!!!

Did that with the two batteries and both now are working GREAT, with the
complete duration expected (3.5 Hours of running time on the notebook (the
one with I am writing right now, powered by one of those batteries :-)).

Now.
It was clear that in my case, the problem was NOT the charger, but the
batterie that had no charge for a long time.

in your case the problem could be the charger, usually sony likes to build
chargers that complete the battery in less than 2 hours, this is kind of fast.

if that's your case, you may try what i did , but after that, charge the
batteries with a slower charger, and probably you'll have both batteries
working
again!, you lose nothing trying it, but take care of noises on the batteries or
temperature, if it's start to warm or make any noise, stop inmediately and
let it rest for a while, it may explode very bad!, it would be a good idea not
to apply these pulses for more than 2 minutes (remember 1 second interval,
about 100 milisecond of current each second, not more).

Finally, this was pure experimental for me, so if you try it do it with care,
i was luckly and did it with lot of care.

I hope that it could bring back your batteries to live again.

see you

Leandro

At 23:10 26/07/02, you wrote:
>I've just had my second Lithium Ion battery lose virtually all of its
>capacity.
>
>My Sony Mavica came with a 2-cell (7.2 volt, 5 Wh) battery pack. After
>a matter of a few months, it started slowly losing capacity. It now
>won't take a charge at all. I'm trying to charge it with the Sony
>charger. Its terminals read only a few 10's of millivolts straight out
>of the charger (and rapidly goes to 0 when I measure it with a
>voltmeter).
>
>Thinking that I just had a lemon, I bought a larger capacity (1850
>mAh, 13+ Wh) replacement battery. This one has slowly lost its
>capacity as well. While its terminals measure 8.4 volts (2 cells, full
>voltage), It only indicates a few minutes remaining battery life when
>I put it in the camera.
>
>Any ideas how to determine what the heck is going on? The charge
>indicator is only lighting for a few seconds when first I put either
>battery in the charger. Any easy way to test the charger's operation?
>Can anyone recommend a way to discharge and/or recondition these
>batteries?
>
>I love the camera but these darned batteries are awfully expensive to
>replace.
>
>Thanks for any suggestions that anyone can offer.
>
>
>Regards, Bob
>
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