Summer is coming and this is the first summer with my X so it's camping season. I recently got a thermoelectric cooler...it's basically like an ice box but you plug it into your 12v plug in the trunk and it will keep the cooler pretty cool for you. Less bulky than my ice box since the X trunk isn't so big with the 3rd row in use, etc. Ideally, when we go camping for 2-4 days, I'd like to just keep it plugged in inside the car all day and night. Is this ok or will the 12v battery go dead on me? i.e., will the big battery charge the 12v battery if it notices that the 12v battery is low? I don't want to be stuck with a dead car that won't open doors, start, etc. while camping in the middle of nowhere. We usually don't drive the car much when camping so the car will mostly just be sitting there.