Ok thanks, hmmmm I'll have to think about if 3 hours is long enough, or reach out to the airline to see if they'll allow a bigger battery pack on board. Currently I fly with a 10Ah in hand luggage. I always get pulled over in security, but never had a problem once they inspect it.
Re mains, in the safari camps I go to (Kruger Park), the huts have mains power, but there's big trees around most of the huts annoyingly, so need to setup the scope quite away from the huts. Some of the huts would probably do, but you can't select a specific hut, you get allocated one once you arrive. So can charge batteries etc during the day.
Re the mount, I'm probably going to get a Skyguider Pro, so that wont need any additional power. I want to do widefield of the LMC, SMC etc so will be using 85-135mm lenses, so a Skyguider should do fine.
I guess I could get another battery for the wife to take with her, she wouldn't be happy though haha!