Here is what I posted in another thread about storing your EV:
When we went to Europe for a month here's what we did.
1. Plugged car in using Mobile Connector. YOU MUST PLUG THE CAR IN.
2. Cut amp draw of Mobile Connector in half in car to taper the draw (reduce load) on the household line. If you are plugged into a Wall Connector reduce the amperage in the car from 48 to 12-16 amps.
3. Set your state of charge to 50%.
4. Turned OFF Century Mode.
5. Turner OFF any remote services you may have recording telemetry on the car.
6. Buy a bunch of IRISH SPRING bars of soap. Break them up into little pieces and sprinkle them all around the tires, under car and outside too. This will supposedly keep any "critters" from making a home in your car and eating the yummy wiring.
7. Make sure your key cards work to open the doors just in case.
8. To save $$ on insurance, stop collision coverage during the time it's garaged. Talk to your insurance company. They probably have a coverage for you that just covers fire, theft, and natural disasters. We were only gone a short time so I didn't do this but 6 months is a chunk of change to consider. DO NOT stop insurance all together. Fire & theft as a minimum.
9. Leave instructions with someone you trust on how the reset the breaker that the mobile connector is plugged into and also how to unplug and replug the mobile connector to the wall and the car.
10. Try to resist checking on the car through your phone every 5 minutes but do check on it periodically. The car needs to know your still there and care about it and that you haven't abandoned it.
The other option is to sell it and buy a new one on return -OR- loan it to me while your gone. I'll take care of it for you
Good luck and enjoy your trip.
-stew