I can never get through to the local Compaq service desk, so I'll try
here. I have a Compaq Presario laptop with a Lithium ion battery. When
I switched on the computer, expecting it to run on its battery, and
after having used it on AC during the day, virtually nothing happened.
(The battery charging green central LED flashed for a bit, then died.)
I thought the battery was dead, although I had had no previous
warning, such as short discharge time. But when I removed the battery
and checked for voltage on the terminals, it showed approximately the
rated voltage of 14.8V across a number of the terminals.
I have not been able to operate on the battery since (leaving it
charging didn't help).
Does it seem as though it is a battery problem (maybe a printed
circuit in the battery), or more a problem with the computer?

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Request for Question Clarification by chromedome-ga on 19 Jun 2002 08:44 PDT

How long have you owned this computer/battery?  Lithium ion batteries
are wonderful, but you won't necessarily get much warning when they
go.

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Clarification of Question by philipa-ga on 19 Jun 2002 11:01 PDT

I can't remember exactly, but I think about 18 months

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Request for Question Clarification by lucason-ga on 25 Jun 2002 13:34 PDT

Please check the following...

Power on the PC on AC power with the battery in place. Does the OS
recognize that the battery is in place? I doen't know which OS you use
but for your refference, on Win98 you can find this under. Start ->
settings -> control panel | power management | power meter. Let me
know what you find.

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Clarification of Question by philipa-ga on 25 Jun 2002 21:13 PDT

lucason: Yes the OS does recognize that the battery is in place. I'm
using Win 98. It tells me that a Li-ion battery is in place, and gives
me details of the battery. It also says that there is less than 1%
charge in the battery. Since posting the question, I have sent the
battery to Compaq for checking, since I don't want to buy a new one if
the old one is still OK, and I couldn't find someone with a battery
for me to try in the computer. But if you have experience with this
type of battery and computer, you may be able to give me an answer
without my having to wait for an answer from Compaq.

It may be your motherboard as well. I own a Dell Latitude Cpi and my
battery works in other identical laptops, but no batteries will work
in this one. Do you know anyone with a similar laptop that you could
test this with? Also check in your BIOS, to whether or not it is
detecting your battery, and how much life it sees in it. When my
motherboard quit recognizing the battery, it still thought it was
working, and at 100%. I imagine if the battery itself died, the BIOS
would recognize it as being at 0%.

Hello,

Typically speaking about Lithium Ion batteries, they last about 2
years.

Reference:
http://216.239.51.100/search?q=cache:uZHrVpq8xmUC:www.cadex.com/download/NA_Li-ion1.pdf+troubleshoot+lithium+ion+battery+current&hl=en

In my searches I was more focused on the current level than the
voltage. The only real way to be sure if it is the battery is to
simulate the same conditions it does when used in circuit.

A) With a power supply that supplies the same current and voltage. If
you hook up the power supply in place of the battery, the laptop will
draw as much current as it needs. If it is drawing more than the rated
current output of the battery, then you know it is probably the
laptop.

B) Checking it against a known good battery. Simply placing a new
battery in there will tell you for sure, but it's always good to know
the why and what of how this works. You can check the internal
resistance of a known good battery, and then check the internal
resistance of yours. Taken from the same reference "As part of natural
aging, the internal resistance of a Li-ion gradually increases due to
cell oxidation."

In laymen terms it means resistance increases because the materials
inside gradually work themselves toward an open condition.

Helping you troubleshoot without actually having the gear in front of
us makes it any guessers game, but if I had to guess - without any
further information, and based on statistics:

This battery has been overcharged.

Hope it helps -

sgtcory

Most people while working leaver their battery inside theiir Laptop. 
But that cycles the Battery badly and soon after (1+ Years), the
battery does not have the power to keep a sustained charge for more
than a few seconds.  I recommend buy a new battery and when you knwo
your not going to use the battery for a long time, take it out and
replace it with the Blank that comes with the Laptop.

Good Luck

LiON batteries, like many batteries should have a maximum life. If you
charge/discharge them semi-regularly then this may interupt the
recharge cycle...

If you...
1) check the contacts,
1) connect a low volt bulb (about the 15V that you report then this is
OK) to the battery to discharge it for 48 hours continuously tops
(till the bulb has been extinguished for about 4-6 hours or so) then
recharge it, this may "recondition it" but as this advice is for NiMH
(SP?) this may not apply but may not hurt all the same...

Anyways all the best and take care, I hope you sort it soon.