Abstract: A mobile power supply device includes a casing having a locating groove extending around the periphery thereof, a battery set and a control unit mounted in the casing and electrically coupled together, a first transmission arm fastened with one end thereof to the casing and receivable in the locating groove and having a first electrical connection terminal located at a distal end thereof electrically connected to the control unit for power output, a first extension arm extended from a middle part thereof and a second electrical connection terminal located at the distal end of the first extension arm and electrically connected to the control unit for power output, and a second transmission arm fastened with one end thereof and receivable in the locating groove of the casing and having a third electrical connection terminal located at a distal end thereof and electrically connected to the control unit for power output.

Abstract: A vehicle emergency rescue device includes a control unit, a charging and discharging circuit, a battery set, an output voltage converter, a computing unit, a connection terminal and a display device. Subject to the functioning of the inner computing unit and the outer display device, the user can know the car battery capacity and status, the charging time required and the time remaining for full battery charge during the operation of the vehicle emergency rescue device to charge the car battery of the vehicle.