A redox flow battery (1A, 1B) comprising: a battery cell; a tank which stores an electrolyte to be supplied to the battery cell; piping (16, 17, 164, 165, 174, 175) which is connected to the battery cell and the tank and configured to circulate the electrolyte; a container which houses the battery cell, the tank, and the piping (16, 17, 164, 165, 174, 175) all together; and a partition wall (4A, 4B) which is provided inside the container and prevents the electrolyte from leaking out of the container, wherein a height of the partition wall (4A, 4B) is equal to or greater than a liquid level height at the time when a predetermined amount of electrolyte leaks into the container as a consequence of damage to the piping (16, 17, 164, 165, 174, 175), the predetermined amount includes the total of an amount equivalent to the volume of the battery cell and an amount equivalent to the volume of the piping (16, 17, 164, 165, 174, 175) wherein the container includes a rectangular bottom, which corresponds to an installation portion, a rectangular top plate, which is arranged so as to face the bottom, a pair of side face portions, which connect long sides of the bottom to long sides of the top plate, a pair of end face portions (23, 23d), which connect short sides of the bottom to short sides of the top plate, an openable and closable door, which is provided on one of the end face portions (23, 23d), and an opening that is opened and closed by the door, wherein the partition wall (4A, 4B) is provided so as to cover at least part of the opening and to face an imaginary plane of the opening. a battery cell; a tank which stores an electrolyte to be supplied to the battery cell; piping (16, 17, 164, 165, 174, 175) which is connected to the battery cell and the tank and configured to circulate the electrolyte; a container which houses the battery cell, the tank, and the piping (16, 17, 164, 165, 174, 175) all together; and a partition wall (4A, 4B) which is provided inside the container and prevents the electrolyte from leaking out of the container, wherein a height of the partition wall (4A, 4B) is equal to or greater than a liquid level height at the time when a predetermined amount of electrolyte leaks into the container as a consequence of damage to the piping (16, 17, 164, 165, 174, 175), the predetermined amount includes the total of an amount equivalent to the volume of the battery cell and an amount equivalent to the volume of the piping (16, 17, 164, 165, 174, 175) wherein the container includes a rectangular bottom, which corresponds to an installation portion, a rectangular top plate, which is arranged so as to face the bottom, a pair of side face portions, which connect long sides of the bottom to long sides of the top plate, a pair of end face portions (23, 23d), which connect short sides of the bottom to short sides of the top plate, an openable and closable door, which is provided on one of the end face portions (23, 23d), and an opening that is opened and closed by the door, wherein the partition wall (4A, 4B) is provided so as to cover at least part of the opening and to face an imaginary plane of the opening. a rectangular bottom, which corresponds to an installation portion, a rectangular top plate, which is arranged so as to face the bottom, a pair of side face portions, which connect long sides of the bottom to long sides of the top plate, a pair of end face portions (23, 23d), which connect short sides of the bottom to short sides of the top plate, an openable and closable door, which is provided on one of the end face portions (23, 23d), and an opening that is opened and closed by the door, wherein the partition wall (4A, 4B) is provided so as to cover at least part of the opening and to face an imaginary plane of the opening.