Need to charge the laptop on the road so I have purchased an in-car USB-C adaptor. It only provide 30w, so it will not power the laptop & charge at the same time (at least I don’t think it will) but it should be able to charge the laptop when not in use. I will give it a try out tomorrow as a test run & see how it goes, because the other option is a Mains Inverter, which is considerably bulkier & also requires the laptop power adaptor as well.
I also have the in-car charger lead for the Canon battery charger, but annoyingly Canon don’t support it on the later 1Dx mk2 & mk3 chargers, so I will have to use some older 1Dx batteries. I really wish that Canon would remember that a lot of users need to work off-grid from time to time.