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I have an Asus U31SD-XH51 laptop running latest Ubuntu 12.04 LTS and I want to know if there is a way to prevent the system from charging the battery unless its charged level dips below 95%?

This is a feature I notice from my Windows 7 partition. According to Asus, while the charge level is at least 95%, the system would not charge in order to prevent deterioration. However, this is not the case on Ubuntu 12.04 because the system would still charge my battery even at 99%.

Anyone shred some light for me?

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up vote 2 down vote accepted

For my model, U31SD-XH51, I simply added "acip_backlight=vendor" to grub and update it. It actually fixing all backlight problem for me. No longer I need to mess with /etc/rc.local or LMT(laptop-mode-tools). If anyone got a U-series, please follow the steps below and give it a shot.

  1. sudo gedit /etc/default/grub
  2. GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"
  3. sudo update-grub

Best of all, the battery charging concern I am having is fixed as well. Now, it won't charge unless dips below 95%.

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