My laptop battery will charge but only about 8% at a time - I have to unplug and discharge 1% then plug back in - why?

First, let me say that your computer appears to use a Lithium-Ion (Li-Ion) battery that does not suffer from the memory effect that the old style Nickel Cadmium (Ni-Cad or Ni-Cd) batteries did even through the 1990s. (The memory effect is why they have been all but abandoned for Nickel Metal Hydride (NiMH) and Lithium-Ion.) Thus, the suggestion that it thinks it is full is not the case. Second, if you are able to eventually get the battery back to 100% by charging it 8%, discharging it 1%, and then charging it up another 8%, it sounds more like there is a problem with the power regulator in the laptop than a problem with the battery itself. If, on the other hand, you are trying to say that you are unable to charge the battery any higher than 8%, according to the Windows XP (or Windows Vista) battery level meter, then there are a couple of other issues that could come into play. (1) Those battery level meters are not always accurate. They make educated guesses and sometimes get their ...  more