The invention provides viable near-infrared fluorochrome labeled cells and in vivo imaging methods for tracking, locating or determining the quantity of the viable cells once they have been administered to a subject. The light-emitting units are disposed on the substrate. The gas pipe 12 is connected to an upper portion of the branching section 5 and the liquid pipe 9 is connected to a lower portion of the collecting section 6. Those detectable faults that exist in the stored fault list are deleted from the stored fault list and those test pattern sequences that are used to detect the detectable faults existing in the stored fault list are registered in a test pattern sequence list as the selected test pattern sequence. The controller coordinates the sleep mode and the standby mode of operations based on a frame count that is generated from an identification number of the remote unit. In the two or more constant-current charging steps, the secondary battery is subjected to constant-current charging at a current Ic of 1 to 5 C until the charge voltage reaches a target voltage Ecs.