Hot to figure out pin out on Laptop Bat.

I have a brand new bat.
It was supplied as a replacement to my my old one 2-3 days before warranty wore out.

For some reason the laptop did not sleep when the power failed. It just ran and ran till it had the bat totally drained.

Now when I power up I get the msg. Can not recognise the bat.

It works fine on the power adapter and detects the power adapter as a Dell 90Watt unit.

My thought process is that if I could charge the bat pack externally till it got some juice and plug it back it the laptop would take over the charging and it would work again.

The reason I need this is to upgrade my bios. Im not allowed to upgrade the bois without a bat.

So the bat pack has 3 pins.
When I chk the voltage out on a scope I get a voltage that swings between +12 Volts and -12 Volts on the scope.

So obvioully there is some circuit in there between the bat and the charging pins. And just conecting +-12 Volts will blow it.

Any idea how the bat is charged or how I can bump start this.
Its a Dell XPS M1530 and its totally sealed. Knifes and prying are not working I will have to saw it open.
Asuming I saw it open how do I charge the battries in there.

 

read this:
http://www.notebookreview.com/default.asp?newsID=4224

I think you could charge each of the cells one by one.

 

I read that and about 100 videos on u-tube.
Im not keen to cut open a bran new bat. If somebody could just tell me which pin was + and which was -
I could hook up an external charger which was the thought.
Or do Lion chargers work different ie. you need a pulsed current.
http://www.batteryuniversity.com/print-partone-12.htm

 

maybe there is another way to fix this.

Can you disconnect the CMOS better, so that the BIOS will be reset.
That may help.