My netbook EEEPC 1005PE died a few years back. The battery was left unchanged for the duration. I have finally replace the motherboard and found the battery dead.
I cracked open the battery using my favorite chisel. The battery shell is actually snapped together. There was a tiny bit of silicon holding on the the PCB.
I measured around 2.95V to 3.0V on the 3 pairs of cells. The undervoltage has set in and the battery management IC has disconnected the battery from the connector for safety. At 3V, I think the battery is still undamaged.
After reaching this voltage, the battery can be charged normally. I gradually increasing current to 150mA. When the battery reaches 3.5V per cell, I thought the battery management IC would be reset, but it didn't.
I found the schematic of an earlier model. I figure that they wouldn't change the schematic too much between models. Pin 3 now has a 470R resistor to ground.
I figured that they probably have a pair of back to back connected MOSFET switch to isolate the battery which normally powers to the battery management IC. So I connected a 100 ohms resistor between the positive terminal of the battery pack to pin 1 momentary. This turns on the MOSFET and the battery management IC which now latches on the MOSFET. The battery pack has now been reset.
Now the netbook can run off the battery, but the battery pack is not being charged. I don't know if the replacement motherboard has a damaged charger or there is something else not working.
Looks like I could have saved the trouble of opening it up by simply connecting my bench supply to 11.1V with a series resistor of 100R to pin 1 and pin 9.
Found an excellent reference: Teardown: Genuine Asus A32-1015 Li-Ion Netbook Battery Pack
Sadly there are no datasheets available for the battery management chip. I saw a board with some Chinese software for programming batteries for sale for something $500 ish (not sure of currency).
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