760 Battery Charging issue

[Medessec]

I just got this nice 760ED in... but I've run into a slight issue with it.

When the battery is plugged in, the power meter shows how much juice is left in it (34% at the moment) and I can power on the laptop from the battery. However, plugging the laptop in doesn't charge the battery, whether the laptop's off or in Windows. It also doesn't matter which bay the battery is installed in(Ultrabay, or Battery Bay).

The battery definitely holds a good charge, since the laptop can be powered off of it, and the laptop can work exclusively off AC power as well(with the battery removed, and the battery isn't drained when it is installed with AC power on). I'm absolutely baffled and I have no idea where to turn. I unfortunately don't have any other 760s or other batteries to test. I believe I did have a dead battery I was able to insert, but it pulls up 0%, and predictably doesn't charge.

[Dant]

Well, trying multiple batteries seems to confirm the issue lies in the charging circuits... but there is a piece of kit you can get to really check to see if that is the case.

There's a device called the IBM Travel Quick Charger (FRU: 85g1526) that will charge batteries externally using the AC adapter from the later 7xx series. Also, it has an output that plugs into the power input on a 7xx series Thinkpad, that allows the battery in the quick charger to act as a second (or third) battery for the system.