1 year old laptop battery is not charging but the AC adapter

File: battpinout.jpg (59KB, 840x888px) Image search: [Google]

59KB, 840x888px

1 year old laptop battery is not charging but the AC adapter is able to power the computer. The adapter is also able to charge a different laptop.

I've replaced the battery with a new one and I'm still getting the same problem. I've checked the connection of the charger to the plug on the laptop using a multimeter and it's passing the voltage to the motherboard fine. The battery pins on the other hand are different:

I have 0V between pins 1 and 8 (+ and -) on both batteries when the adapter is not plugged in.

On the new battery: 0V when testing pins 1-7 in reference to 8 without charger. With charger (reference is 8):
1: 2.5
2: 2.5
3: 3.2
4: 3.2
5: 0
6: 0
7: 0


On the old battery: without charger (reference is 8):
1: 8.8
2: 8.8
3: 0
4: 0
5: 0
6: 0
7: 0

With charger (reference is 8):
1: 9.3
2: 9.34
3: 3.2
4: 3.2
5: 0
6: 0
7: 0

What exactly is the problem? Other than the 0V on the new battery without charger the other pins seem to be acting normally. Did I just get unlucky and get a dead new battery?