PURPOSE: To simplify the operation by taking out a battery from an unmanned battery vehicle stopping at a battery replacing position, setting the battery to a charging section, then taking out the charged battery and setting to the battery vehicle.

CONSTITUTION: When a battery vehicle 14 stops at a battery replacing position, a transfer unit 12 functions to hold a battery case 16. Then sliders 28, 30, 32 return to original positions. Thereafter, a lift functions to lift an elevatable body to a position corresponding to a specific shelf 20. Then a battery case 16 held at a fork section 34 is positioned above the shelf 20. Thereafter, the battery case 16 being held at the fork section 34 is mounted on the shelf 20 and the fork section 34 is pulled in. Then the fork section 34 takes out the battery case 16 containing a charged battery 22.