I recall flying to Qld for the on-road nats a number of years ago, and we were able to avoid excess baggage charges by advising the airline at check-in the case contained "sporting gear" (well, that was sort of true). Unsure if that's a thing these days, but worth checking with your airline.
Obvs lipo's will need to go carry-on, also check with your airline regarding the capacity as there are limits to the battery capacity you can carry in some places (it's actually the Watt Hrs they're interested in) - though my laptop and phone powerbanks (around 45,000mAh total, each under 100 watt hours) have never been an issue internationally or domestically here or the USA. Worth being aware of so there aren't any surprises.
https://www.casa.gov.au/standard-pag...fely-batteries (note the bad battery examples are all RC car batteries!
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