Abstract: An energy storage apparatus used in a flight vehicle includes battery circuits connected in series, through which current flows during charge and discharge of the energy storage apparatus. Each of the battery circuits includes: a first electrical path; an energy storage cell connected to an adjacent battery circuit through the first electrical path; a first switch that includes a diode and is provided in the first electrical path such that a forward direction of the diode is a charge direction of the energy storage apparatus; a second electrical path connected to the adjacent battery circuit in parallel with the energy storage cell and the first switch; and a second switch that includes a diode and is provided in the second electrical path such that a forward direction of the diode is a discharge direction of the energy storage apparatus, and is turned on when the first switch is turned off.