Electric automobile mobile energy storage device and switching control method using same

The embodiment of the invention discloses an electric automobile mobile energy storage device and a switching control method using the same. The energy storage device comprises a trailer, a battery system, a current conversion system, a high-voltage connection assembly and a low-voltage connection assembly, wherein the battery system, the current conversion system, the high-voltage connection assembly and the low-voltage connection assembly are arranged on the trailer; the trailer is used for being detachably connected with an electric automobile and can move along with the electric automobile; the current conversion system is connected with the electric automobile through the high-voltage connection assembly so as to realize high-voltage energy transmission, and the charging and outward discharging of the battery system; the current conversion system is connected with the electric automobile through the low-voltage connection assembly so as to realize the low-voltage electric connection with the battery syst