Arch Linux

AmmoniumX

Member

Registered: 2024-09-27

Posts: 5

Custom Battery Charge Thresholds on Dell G3 3579

Hi all,
I have converted an old laptop into a homemade server, and I would like to control the thresholds when the battery starts/stops charging to increase its longevity. I am aware that removing the battery would probably be ideal for maximizing longevity, but I still want to keep the battery.

I have tried two approaches: tlp and smbios-battery-ctl (from libsmbios). However, neither of them have detected my battery correctly. Fastfetch is able to read it, so I am unsure what I'm doing wrong.

Has anybody had any luck before for setting custom charging thresholds on similar dell laptops?

Here's more information on the utilities I've tried:
Libsmbios:

❯ sudo smbios-battery-ctl -v -c
Libsmbios version : 2.4.3
smbios-battery-ctl version : 2.4.3
 You can use smbios-battery-ctl utility to view/modify battery settings
 Get Charging State : res[smi.cbRES1]=0x0,res[smi.cbRES2]=0x0, res[smi.cbRES3]=0x0

 Supported battery charging features:
         NIL

 Battery charging Status:
         NIL

TLP:

❯ sudo tlp-stat -b
--- TLP 1.6.1 --------------------------------------------

+++ Battery Care
Plugin: generic
Supported features: none available

+++ Battery Status: BAT0
/sys/class/power_supply/BAT0/manufacturer                   = LGC-LGC3.553
/sys/class/power_supply/BAT0/model_name                     = DELL 81PF3
/sys/class/power_supply/BAT0/cycle_count                    =      0 (or not supported)
/sys/class/power_supply/BAT0/charge_full_design             =   3680 [mAh]
/sys/class/power_supply/BAT0/charge_full                    =   3680 [mAh]
/sys/class/power_supply/BAT0/charge_now                     =   3680 [mAh]
/sys/class/power_supply/BAT0/current_now                    =      1 [mA]
/sys/class/power_supply/BAT0/status                         = Full

/sys/class/power_supply/BAT0/charge_control_start_threshold = (not available)
/sys/class/power_supply/BAT0/charge_control_end_threshold   = (not available)

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

Just to show fastfetch reads it fine:

❯ fastfetch -l none | grep -i battery
Battery (DELL 81PF3): 100% [AC Connected]

linrunner

Member

Registered: 2013-04-21

Posts: 55

Re: Custom Battery Charge Thresholds on Dell G3 3579

Hi,

the solution is just around the corner:  /sys/class/power_supply/BAT0/charge_control_start_threshold, charge_control_end_threshold  come with kernel 6.11 (which just arrived in Arch) and will then probably be followed by a Dell plugin in TLP 1.8 - if there are enough brave testers.

https://github.com/linrunner/TLP/issues … 2385155103

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Regards, linrunner

TLP – Linux Advanced Power Management