Charging method, charging circuit, and charging device

摘要

When charging of a secondary battery (13) is started, a power source section (37) for supplying an electric current for charging the secondary battery gradually increases the supply amount of the current. If the charging current has reached a predetermined first threshold current, the power source section is operative to set the supply amount of the current to a predetermined constant current for a constant current charging. If a terminal voltage of the secondary battery has reached a predetermined threshold voltage, the power source section is operative to supply a predetermined voltage for a constant voltage charging to the secondary battery.