Leaving the Kona for 8-10 weeks.

Have the charge in the middle, 60% or so. Some people say you should disconnect the 12V battery, but I don't think so. There is no phantom drain on the Hyundai's and after a few days of feeling lonely it will shut itself down completely and won't even respond to blue link requests any more. I doubt you will see more than 1% loss in SOC.

But like I said, some people prefer to disconnect the 12V.

 

You need to specify the expected ambient temperature.

 

Does your Kona have a "battery reset" tab on the lower dash, to the left of your steering wheel?

 

In similar temps I let mine sit for 6 weeks with no issues at all, perhaps 1% loss of main battery charge which I left at 65%.
If you haven't had any prior issues with the 12V battery I'd suggest there's no need to disconnect it, but there's also no downside to doing that either.
It will automatically get a charge off the main battery for 20 minutes once a day.

 

If there's no reset switch, I'm unsure that you have the "battery saving" feature. A trickle charger connected to the 12 v battery (if you can find it) might be prudent.

 

Every Kona has the battery saver feature. Mine didn't have the reset switch and had it. All have them because the 12V battery has to be charged by the high voltage battery at some point. Otherwise they all would definitely die. Mine worked great for almost 3 years (then I returned the Kona for the HV battery recall).

 

Yeah, this is a relatively short storage period in a favourable ambient temperature. It appears risk-free.