Krzyszkowiak also reports that charging in the Librem 5 is currently limited to 0.5 amps, so current charging is limited to 5Vx0.5A (2.5W), 9Vx0.5A (4.5W) and 12Vx0.5A (6W), but the code to vary the amperage is waiting to be accepted upstream, so that should be solved soon.
From here: