Best solution for leaving Kona without charging for about a month and a half

I expect it'll be fine and assuming no other environmental circumstances you'll only lose about 1%. Mine was parked outside over 5 weeks of lockdown in approx 18°C ambient with no problems and I monitored it daily.

You could disconnect the 12V battery but I don't see that it's necessary and you can use your app to check on it. After sitting parked for over 60 hours the car will automatically charge it every day off the traction battery.

 

No need to do anything but best not leave the main battery over 80% for long periods

 

…and below 20% as well.

 

Just recently I left my Kona parked for just over six weeks and the battery level was around 60%. It was fine when I got back home and as was mentioned the battery level change was insignificant. I kept it in my garage for reference sake.

 

Might want to deactivate Winter Mode. Leave it at 65%, it can stay for months like that.

 

The winter mode setting is not relevant when the car is parked and not charging.

 

Just need a 10mm ratchet wrench or spanner wrench to loosen connector bolt on negative terminal and wiggle until connector comes off or you can do the same to the positive terminal if you like(try not to ground yourself with wrench if negative terminal is still attached), similar to the picture below.