If you install i3wm and i3status fail to detect your battery, here's one solution:

Open /etc/i3status.conf and look for "battery 0 {". Add the following line inside the battery config:

path = "/sys/class/power_supply/BAT1/uevent"

The location might differ, so navigate to power_supply and find the BATX appropriate for you. I've seen someone use BAT%d in their config (%d would refer to an integer), but I havn't tested it.

i3status should now automatically detect your battery, log out or reboot to see the changes.