My father just got a new 750Li a few months ago, and after a thanksgiving dinner we came out to the car and it wouldn't start. the car was entirely dead, including no interior lights -- nothing. 2.5 hours later the car was towed back to the shop... the dealer's reasoning was that my father hadn't driven the car enough prior to that short trip for thanksgiving and that the battery was therefore drained by the extensive computer systems. he was urged to buy a trickle charger (which he did) -- to help supplement and support the battery's efficiency. has anyone else had this experience with such a new car? is it realistic to believe that the car must be driven a minimum amount in order to avoid such a catastrophic drain? any suggestions to get him to ease his mind or to change driving habits to avoid that in the future would be greatly appreciated. thanks for any help.