The OP has a 2016 Leaf. From 2014 or 2015 on, there is no sign of the 12 volt charging issues seen with earlier Leafs. With no telematics "upgrade" to drain power and no known charging issues, what I originally wrote stands. I usually tell people to use a maintainer, but in the above case the very most that should be needed is fully charging the 12 volt battery with an external charger before parking it.
2013 "Brilliant Silver" SV with Premium Package and no QC, and 2009 Vectrix VX-1 with 18 Leaf cells.
The most offensive, tasteless phrase in use here is "Pulled the trigger." I no longer respond to posts that use it.