Abstract: The present invention provides a complete-circulation-type bio-toilet system in which adjustment tanks capable of storing water to be treated are arranged before and after a septic tank, thereby enabling stable provision of the system without stopping the system even when the system is in heavy use.

Abstract: The present invention provides a battery charger capable of charging a plurality of secondary batteries which are used in different types of apparatuses, such as an electric vehicle and a mobile power supply unit, in a simultaneous or concurrent manner without largely occupying an installation space on the ground. A DC power supply section 22 includes a plurality of DC stabilized power supply circuits each operable to supply an output according to required electric power, therefrom in an independent manner. Specifically, based on information from each of a plurality of secondary batteries, and information set up/input through a setup/input section, one of or a combination of two or more of the DC stabilized power supply circuits is selected for each of the secondary batteries.