A boost converter disclosed herein may include boost circuits including: a diode including a cathode connected to a high-potential output wiring; a switching element including a terminal connected to an anode of the diode and a terminal connected to a low-potential wiring; and a reactor connected between the high-potential input wiring and the anode. A control circuit may energize, in a first operation, a first boost circuit when charge current is in a first range, and energize the first and a second boost circuits when the charge current is in a second range larger than the first range. The control circuit may energize, in a second operation, a third boost circuit when the charge current is in the first range, and energize the third and a fourth boost circuits when the charge current is in the second range. The first boost circuit is other than the third boost circuit.