The new IBM ThinkPad T21 Battery does not charge, Why?
All laptop battery manufacturer in the ship, the laptop battery will charge 40-50 of electricity. In general we recommend charging a night (about 12 hours).
The initial use of a New IBM ThinkPad T21 Battery should be rechargeable (depth charge, and then the depth of discharge), 3 to 5 times, so that optimal battery performance. (Note: the battery during charging and discharging process of a certain temperature is normal). It's hard to charge a new battery adapter, because they never depth charge. If this happens, remove the battery and then re-inserted. Charge cycle should start again. The first charge the IBM ThinkPad T21 Battery several times when this may happen. Do not worry, this is completely normal.
Anyway,Buy a high quality IBM ThinkPad T21 Battery is your best choose!