Is there any way to stop charging no matter the battery level?

[marcmerlin]

When powering from an external USB battery pack, I want to power the laptop only, not to charge its batteries. That's easy to do on thinkpad, but with dell, all I have is
/opt/dell/dcc/cctk --PrimaryBattChargeCfg=Custom:50-55
but this only works if the battery is still over 55%.
Is there anything better, or that's the best there is?

[Niels-bt]

I think it's the best you can do.
You can always check if you like to.
sudo /opt/dell/dcc/cctk -S --keyword=batt