Since the end of 2012 I have a Lenovo X1 Carbon laptop running with Ubuntu 12.04
By default a laptop charges all the way up to 100% State of Charge, something which is very bad for a battery. There is a great video on Youtube about this if you want to know all the ins and outs.
The bottom line is that I wanted to limit the charge level to 90% for my laptop. Up until now I did this manually by pulling the plug at certain points, but that didn’t always work. I sometimes forgot and the battery would charge up to 100%.
On Github I found the tpacpi-bat project which allows you to limit the charge level of your battery.
How to install?
- Clone the project
- Run install.pl
- Modify your /etc/rc.local file
This is what you need to put in your rc.local:
tpacpi-bat -g SP 0 tpacpi-bat -g SP 1 tpacpi-bat -g SP 2 exit 0
As far as I know the X1 Carbon has 3 batteries, so for all three we set the charge limit to 90%. This is not persistent after reboots, so we have to set it every time we boot.
You’ll now see that your battery charges to 90% at max.