This. I have the one from Costco for when one of my cars sits for a while. Great little device!Just a thought, but if your goal is to keep the battery in good shape, you could get a battery tender.
I have the same maintainer and was able to prolong the battery life on my BMW for another year after getting low battery warnings. Sold the car, so I'm not sure how it's holding up now. Need to use this on the Ody now!I have this one, also a Battery Tender but different than the one in the Costco link above:
Battery Tender Plus Maintainer and Charger
As far as disconnecting your battery to prevent parasitic loss versus hooking up a maintainer, I think the latter is better for the long-term health and longevity of your battery. I use the Battery Tender on my '08 Jetta, which at this point is a third weekend/sunny day car. Works great as a maintainer (note the one I have isn't beefy enough to charge the car battery).