Having run my car down to around 30 miles left on Christmas eve, I decided as I didn't require the car for the next two days so I set the charge limit to 50% for any emergencys. When the charge finished I left the lead connected. Is there any reason not to leave it connected until I next need to drive away? My thought is when I next use it I can heat the car up and I guess the charger will top up the battery back to my charge limit. Am I correct or is there a problem leaving the car connected?