Set Dell Battery Charge Limits on Linux with cctk
Published:
Lithium-ion batteries degrade faster when they sit at 100%, especially if the laptop stays plugged in. On a Dell machine, the practical fix is a charge window: stop at 80%, resume only after it drops below 50%.
On a Dell Latitude 5501 (Ubuntu 24.04), smbios-battery-ctl looked like the right tool—but it only reads. Setting thresholds appeared to succeed and then silently did nothing. The working path is Dell Command | Configure (cctk), which talks to the low-level Dell driver (/dev/dcdbas) and commits limits to the Embedded Controller. |
- Why smbios-battery-ctl fails on Latitude 5501
- Install Dell Command | Configure (cctk)
- Set charge limits with cctk
- Verify
Why smbios-battery-ctl fails on Latitude 5501
Querying works:
sudo smbios-battery-ctl --get-charging-cfg
Charging mode: custom
Charging interval: (50, 80)
Setting looks successful, then nothing changes:
sudo smbios-battery-ctl --set-custom-charge-interval 50 100
Custom charge interval has been set to (50, 100)
sudo smbios-battery-ctl --get-charging-cfg
Charging mode: custom
Charging interval: (50, 80)
smbios-battery-ctl writes via userspace SMBIOS WMI tokens in NVRAM. On this generation of Dell business laptops, the EC ignores those tokens unless the update goes through Dell’s ring-0 ACPI path. So libsmbios is effectively read-only here.
Install Dell Command | Configure (cctk)
| Download **Dell Command | Configure Application** from Dell Support for the Latitude 5501: |
On that page, select:
Dell Command | Configure Application
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Systems Management
The package used here was:
command-configure_4.10.0-595.ubuntu18_amd64.tar.gz
It is labeled for Ubuntu 18.04, but it works on Ubuntu 24.04.
| Extract, then install the HAPI backend first, then Command | Configure: |
cd /path/to/command-configure_ubuntu_amd64/
sudo apt install ./srvadmin-hapi_*_amd64.deb
sudo apt install ./command-configure_*_amd64.deb
OpenSSL 1.1 on Ubuntu 22.04 / 24.04
If cctk fails looking for libcrypto.so.1.1:
wget http://security.ubuntu.com/ubuntu/pool/main/o/openssl/libssl1.1_1.1.1f-1ubuntu2.24_amd64.deb
sudo dpkg -i libssl1.1_1.1.1f-1ubuntu2.24_amd64.deb
Optional PATH shortcut
The binary lands at /opt/dell/dcc/cctk:
sudo ln -s /opt/dell/dcc/cctk /usr/local/bin/cctk
Set charge limits with cctk
The primary-battery option is --PrimaryBattChargeCfg (Batt, not Battery).
Check current setting:
sudo cctk --PrimaryBattChargeCfg
Set custom start/stop (50%–80%):
sudo cctk --PrimaryBattChargeCfg=Custom:50-80
If a BIOS setup password is set:
sudo cctk --PrimaryBattChargeCfg=Custom:50-80 --ValSetupPwd=YourPassword
For a full charge before travel:
sudo cctk --PrimaryBattChargeCfg=Standard
Other profiles: Express, Adaptive, PrimAC.
Verify
sudo cctk --PrimaryBattChargeCfg
Expected:
PrimaryBattChargeCfg=Custom:50-80
These settings commit to the EC and persist across reboot, dual-boot, and OS reinstall.