How to fix battery indication in debian squeeze on Acer Aspire
Problem: acpi could not detect battery status, and shows unkown battery as:
Battery 0: Unknown, 0%
Firstly, if you are on Acer Aspire xxxx (mine is Aspire 4745G), you need to upgrade the bios to a new version (such as BIOS_Acer_1.25_A_A.zip for 4745G).Just download the bios program here:
Secondly, enable acpi on boot option in /boot/grub/grub.cfg:
linux /boot/vmlinuz-2.6.32-5-amd64 root=/dev/hda9 ro acpi=on quiet
Then install powertop to check which process consumes lots of power,and cpufrequtils, laptop-mode-tools to automatically save your power.
sudo apt-get install powertop cpufrequtils laptop-mode-tools
restart you system.