A battery pack heating apparatus, applicable portably and externally to a vehicle, characterized in comprising: an electrical energy conversion component, comprising an energy storage device, a first set of switches and a second set of switches; a heating interface component comprising a plurality of heating interfaces connected to the energy storage device via the first set of switches to form a first heating loop and connected to the energy storage device via the second set of switches to form a second heating loop, each of the plurality of heating interfaces being configured to be connected to a battery pack of one vehicle; and a heating control module configured to control the electrical energy conversion component to be discharged to the battery pack and to control the electrical energy conversion component to be charged by the battery pack in such a manner that an electrical energy transfer between the electrical energy conversion component and the battery pack is established, so that the battery pack is heated directly by means of charging and discharging; wherein the heating interface component further comprises: a plurality of main loop switch devices connected in series to the plurality of heating interfaces, any two neighboring main loop switch devices having one heating interface connected therebetween and any two neighboring heating interfaces having one main loop switch device connected therebetween, a positive connection terminal of the heating interface component being a terminal of the plurality of main loop switch devices that is directly connected with none of the plurality of heating interfaces, and a negative connection terminal of the heating interface component being a terminal of the plurality of heating interfaces that is directly connected with none of the plurality of main loop switch devices, wherein each of the plurality of main loop switch devices is configured to disable an electrical energy transfer between the battery pack heating apparatus and the battery pack in case of an abnormality. an electrical energy conversion component, comprising an energy storage device, a first set of switches and a second set of switches; a heating interface component comprising a plurality of heating interfaces connected to the energy storage device via the first set of switches to form a first heating loop and connected to the energy storage device via the second set of switches to form a second heating loop, each of the plurality of heating interfaces being configured to be connected to a battery pack of one vehicle; and a heating control module configured to control the electrical energy conversion component to be discharged to the battery pack and to control the electrical energy conversion component to be charged by the battery pack in such a manner that an electrical energy transfer between the electrical energy conversion component and the battery pack is established, so that the battery pack is heated directly by means of charging and discharging; wherein the heating interface component further comprises: a plurality of main loop switch devices connected in series to the plurality of heating interfaces, any two neighboring main loop switch devices having one heating interface connected therebetween and any two neighboring heating interfaces having one main loop switch device connected therebetween, a positive connection terminal of the heating interface component being a terminal of the plurality of main loop switch devices that is directly connected with none of the plurality of heating interfaces, and a negative connection terminal of the heating interface component being a terminal of the plurality of heating interfaces that is directly connected with none of the plurality of main loop switch devices, wherein each of the plurality of main loop switch devices is configured to disable an electrical energy transfer between the battery pack heating apparatus and the battery pack in case of an abnormality. a plurality of main loop switch devices connected in series to the plurality of heating interfaces, any two neighboring main loop switch devices having one heating interface connected therebetween and any two neighboring heating interfaces having one main loop switch device connected therebetween, a positive connection terminal of the heating interface component being a terminal of the plurality of main loop switch devices that is directly connected with none of the plurality of heating interfaces, and a negative connection terminal of the heating interface component being a terminal of the plurality of heating interfaces that is directly connected with none of the plurality of main loop switch devices, wherein each of the plurality of main loop switch devices is configured to disable an electrical energy transfer between the battery pack heating apparatus and the battery pack in case of an abnormality.