With 3 batteries and around 1 hour charge time per battery, it would be possible to keep the Mini 2 in flight nearly continously while changing batteries every 30 minutes.

What is the duty cycle of the Mini 2? Can it support that kind of operation for extended periods?

It has generally been advised to let batteries cool back to ambient, before recharging, I have read.  Estimating cool-down time to be perhaps 30 minutes (depending on ambient temperature) you might calculate that you would need four batteries in order to achieve what you plan on doing.  I for one wouldn't want to take a hot/used battery straight out of the drone and stick it on charge immediately.

Blériot53 Posted at 10-29 14:47
It has generally been advised to let batteries cool back to ambient, before recharging, I have read.  Estimating cool-down time to be perhaps 30 minutes (depending on ambient temperature) you might calculate that you would need four batteries in order to achieve what you plan on doing.  I for one wouldn't want to take a hot/used battery straight out of the drone and stick it on charge immediately.

I for one wouldn't want to take a hot/used battery straight out of the drone and stick it on charge immediately.
If the battery is too warm, it won't charge anyway.

What is the duty cycle of the Mini 2? Can it support that kind of operation for extended periods?
If you had 20 charged batteries, you could fly them all without any concern.

I can't report on the Mini 2 but I have often gone through 3 batteries in just over an hour total on the MA2 with no problems...and I live in Florida and very often fly in sport mode. I have not tried a quick change after charging however.

It sounds like 4 batteries may be the magic number. Use battery, replace and let cool down. When you land and swap the next battery, the previous battery gets charged now it is at ambient. repeat.

Pretty sure 4 batteries would be the sweet spot to accomplish what you are wanting to do.  Like others have said just cool down the battery a bit before trying to charge or the battery will not charge.

I think 30 minutes cooldown is way too high, I think around the 10-minute mark is cooled down ample enough to safely charge, well, certainly for here in the UK.
Using a fast charger can cut your charging time in half too, i have one for the car (66w dual) and home (65w triple) the latter charges the 3 in the hub, 1 in the AC and the controller at the same time at a fast charge, no issues so far and now on 20+ charges before anyone says they will damage the batteries.