An apparatus for variably controlling the variable disconnection of physical connections between battery assembly units, the apparatus comprising: a sensor module, switches, a switch control module and a disconnection control module, wherein the sensor module is placed outside the battery assembly units and configured to sense one of temperature, humidity, electrical short, flood and earthquake indicative of a current situation of the outside in real time and transmit to the disconnection control module current situation data based on the sensed temperature, humidity, electrical short, flood or earthquake; the switch control module is adapted to apply on/off signals to the switches; and the battery assembly units are in series, two adjacent battery assembly units being interconnected through an interconnection line; the disconnection control module is adapted to receive the current situation data from the sensor module; characterized in that: at each interconnection line between two adjacent battery assembly units, one of the switches is provided to electrically connect and disconnect the interconnection lines; and the disconnection control module is further adapted to judge a danger level of the current situation based on the current situation data, determine a disconnection level based on the danger level so that the higher the danger level, the more shortened the disconnection intervals of the battery assembly units, and control the switch control module based on the danger level to vary the location and number of the target switches to be opened or closed and the disconnection intervals. a sensor module, switches, a switch control module and a disconnection control module, wherein the sensor module is placed outside the battery assembly units and configured to sense one of temperature, humidity, electrical short, flood and earthquake indicative of a current situation of the outside in real time and transmit to the disconnection control module current situation data based on the sensed temperature, humidity, electrical short, flood or earthquake; the switch control module is adapted to apply on/off signals to the switches; and the battery assembly units are in series, two adjacent battery assembly units being interconnected through an interconnection line; the disconnection control module is adapted to receive the current situation data from the sensor module; characterized in that: at each interconnection line between two adjacent battery assembly units, one of the switches is provided to electrically connect and disconnect the interconnection lines; and the disconnection control module is further adapted to judge a danger level of the current situation based on the current situation data, determine a disconnection level based on the danger level so that the higher the danger level, the more shortened the disconnection intervals of the battery assembly units, and control the switch control module based on the danger level to vary the location and number of the target switches to be opened or closed and the disconnection intervals. at each interconnection line between two adjacent battery assembly units, one of the switches is provided to electrically connect and disconnect the interconnection lines; and the disconnection control module is further adapted to judge a danger level of the current situation based on the current situation data, determine a disconnection level based on the danger level so that the higher the danger level, the more shortened the disconnection intervals of the battery assembly units, and control the switch control module based on the danger level to vary the location and number of the target switches to be opened or closed and the disconnection intervals.