Electric vehicle battery heat preservation control method, device and system and electric vehicle

The embodiment of the invention provides an electric vehicle battery heat preservation control method, device and system and an electric vehicle, and relates to the technical field of electric vehicles. The electric vehicle battery heat preservation control method comprises the steps that first heat preservation duration set by a user is obtained through a multimedia vehicle machine, and charging heat preservation duration is updated to be the first heat preservation duration; whether the battery heat preservation action is allowed to be executed or not is judged by combining the whole vehicle state of the electric vehicle; when the battery heat preservation action is allowed to be executed, the battery heat preservation action is executed according to the charging heat preservation duration. According to the embodiment of the invention, battery heat preservation control can be carried out according to different travel requirements of users, and the technical effect that the battery performance of the electri