tpacpi-bat is a script using acpi_call kernel module which allows one to set battery charge thresholds on new ThinkPad models not supported by Tp_smapi.
- tpacpi-bat: https://github.com/teleshoes/tpacpi-bat
- acpi_call: https://github.com/mkottman/acpi_call
Ubuntu / LinuxMint
You can use this PPA
Packages are available for ArchLinux: https://aur.archlinux.org/packages.php?ID=54293
You need to build from source.