TLP is an advanced power management tool I use for my laptop that runs Linux. I have not tested the different settings, but it seems that the battery time is increased compared to not running it. :-) I only use it in battery-mode. There are some extra features for Thinkpad laptops.
TLP settings file Ubuntu: /etc/tlp.conf
Reload config: sudo tlp start
Check TLP status: sudo tlp-stat
Check battery: upower -i /org/freedesktop/UPower/devices/battery_BAT0
Set charge: sudo tlp setcharge 40 80
Battery status 2021-12-06:
+++ Battery Features: Charge Thresholds and Recalibrate
natacpi = active (data, thresholds)
tpacpi-bat = inactive (kernel module 'acpi_call' load error)
tp-smapi = inactive (ThinkPad not supported)+++ ThinkPad Battery Status: BAT0
/sys/class/power_supply/BAT0/manufacturer = Celxpert
/sys/class/power_supply/BAT0/model_name = 5B10W139
/sys/class/power_supply/BAT0/cycle_count = 380
/sys/class/power_supply/BAT0/energy_full_design = 57000 [mWh]
/sys/class/power_supply/BAT0/energy_full = 47510 [mWh]
/sys/class/power_supply/BAT0/energy_now = 37540 [mWh]
/sys/class/power_supply/BAT0/power_now = 0 [mW]
/sys/class/power_supply/BAT0/status = Unknown (threshold may prevent charging)/sys/class/power_supply/BAT0/charge_start_threshold = 40 [%]
/sys/class/power_supply/BAT0/charge_stop_threshold = 80 [%]Charge = 79.0 [%]
Capacity = 83.4 [%]gnowak@t495s:~$