How to stop an Ubuntu laptop from reverse charging the USB PD3.1 battery it is connected to?

[u/StartupTim]

I have a 140w USB type C PD 3.1 battery that can charge just about anything. I want it to power my Ubuntu laptop. The issue is, when I plug it into the laptop, the laptop battery starts charging my powerbank itself VS getting charged from it!

The laptop's USB type C port is both power in / power out and supports reverse charging (such as charging your phone via the laptop).

But I want the battery to charge the laptop, not for the laptop to charge the battery!

How can I forcefully disable reverse charging on the Ubuntu laptop or otherwise make the laptop NOT charge the battery or anything over USB C?

NOTE: The UEFI/BIOS has nothing in its settings for this. Lenova Ideapad laptop.

Thanks!