对于经常接AC的用户来说，电池保持在40%-80%之间可以让电池生命周期更长久
由于我的t460s有两块电池，分别设置
linux-pw37:~ # cat /etc/default/tlp
# Battery charge thresholds (ThinkPad only, tp-smapi or acpi-call kernel module
# required). Charging starts when the remaining capacity falls below the
# START_CHARGE_THRESH value and stops when exceeding the STOP_CHARGE_THRESH value.
# Main / Internal battery (values in %)
START_CHARGE_THRESH_BAT0=40
STOP_CHARGE_THRESH_BAT0=80
# Ultrabay / Slice / Replaceable battery (values in %)
START_CHARGE_THRESH_BAT1=40
STOP_CHARGE_THRESH_BAT1=80

重启tlp.service

linux-pw37:~ # systemctl restart tlp.service
linux-pw37:~ # tlp stat -v -b               
--- TLP 0.9 --------------------------------------------

+++ ThinkPad Extended Battery Functions
tp-smapi   = inactive (unsupported hardware)
tpacpi-bat = active

+++ ThinkPad Battery Status: BAT0 (Main / Internal)
/sys/class/power_supply/BAT0/manufacturer                   = SMP
/sys/class/power_supply/BAT0/model_name                     = 00HW023
/sys/class/power_supply/BAT0/cycle_count                    = (not supported)
/sys/class/power_supply/BAT0/energy_full_design             =  23540 [mWh]
/sys/class/power_supply/BAT0/energy_full                    =  24100 [mWh]
/sys/class/power_supply/BAT0/energy_now                     =  24090 [mWh]
/sys/class/power_supply/BAT0/power_now                      =      0 [mW]
/sys/class/power_supply/BAT0/status                         = Unknown (threshold effective)

tpacpi-bat.BAT0.startThreshold                              =     40 [%]
tpacpi-bat.BAT0.stopThreshold                               =     80 [%]
tpacpi-bat.BAT0.forceDischarge                              =      0

Charge                                                      =  100.0 [%]
Capacity                                                    =  102.4 [%]

+++ ThinkPad Battery Status: BAT1 (Ultrabay / Slice / Replaceable)
/sys/class/power_supply/BAT1/manufacturer                   = SANYO
/sys/class/power_supply/BAT1/model_name                     = 01AV405
/sys/class/power_supply/BAT1/cycle_count                    = (not supported)
/sys/class/power_supply/BAT1/energy_full_design             =  26330 [mWh]
/sys/class/power_supply/BAT1/energy_full                    =  28230 [mWh]
/sys/class/power_supply/BAT1/energy_now                     =  28230 [mWh]
/sys/class/power_supply/BAT1/power_now                      =      0 [mW]
/sys/class/power_supply/BAT1/status                         = Full

tpacpi-bat.BAT1.startThreshold                              =     40 [%]
tpacpi-bat.BAT1.stopThreshold                               =     80 [%]
tpacpi-bat.BAT1.forceDischarge                              =      0

Charge                                                      =  100.0 [%]
Capacity                                                    =  107.2 [%]

下面是tlp官方的介绍
http://linrunner.de/en/tlp/docs/tlp-configuration.html

ThinkPad Battery Charge Thresholds

ThinkPads only

Set ThinkPad battery charge thresholds for main battery (BAT0) and auxiliary/Ultrabay battery (BAT1). Values are given as a percentage of the full capacity. A value of 0 is translated to the hardware defaults 96 / 100%.

Charging starts upon connecting AC power, but only if the remaining capacity is below the value of START_CHARGE_TRESH (start threshold). Charging stops when reaching the STOP_CHARGE_TRESH (stop threshold) value. If, however when you connect the AC adapter, charge is above the start threshold, then it will not charge.

Note: the charge threshold settings are disabled by default and must be enabled explicitly by removing the leading '#'.

ThinkPad T420(s)/T520/W520/X220 (and all newer models): check erratic battery behavior (FAQ).

For further questions concerning charge thresholds please visit the TLP FAQ.