I just upgraded to Ubuntu 12.10 and the battery indicator is still not working when unplugged from AC power. Nonetheless, I tried what Norman said about suspending and waking the computer and I could see my real battery status for a while (afterwards it went wrong again with an icon indicating as if it was charging when it is not). Thanks again to everyone and hope this hint leads to a solution!
I just upgraded to Ubuntu 12.10 and the battery indicator is still not working when unplugged from AC power. Nonetheless, I tried what Norman said about suspending and waking the computer and I could see my real battery status for a while (afterwards it went wrong again with an icon indicating as if it was charging when it is not). Thanks again to everyone and hope this hint leads to a solution!