I have a 2016 A Class. Nowadays it's used much less often and then it tends to be for short journeys. The start-stop (which I know is a sensitive beast) rarely works and this tells me the battery probably isn't getting the necessary charge. Is there a type of charger I can buy which I could use without disconnecting the battery? I would much rather this and don't want any bother with any resulting issues that might bring. Any help appreciated as I can imagine the battery letting me down at some point in the future.