Which side of battery do you disconnect to stop the running down in a vehicle not being used for while?
The negative terminal of the battery should be disconnected to stop the battery from running down in a vehicle that is not being used for a while. This is because the negative terminal is the ground for the electrical system, and disconnecting it will break the circuit and prevent any current from flowing. Disconnecting the positive terminal would be dangerous, as it could cause a spark and ignite any nearby flammable materials.