An energy storage apparatus, comprising: a chamber comprising a first sidewall; a second sidewall positioned perpendicularly to the first sidewall; a third sidewall facing the first sidewall and positioned perpendicularly to the second sidewall; and a fourth sidewall facing the second sidewall 120) and positioned perpendicularly to the first sidewall and the third sidewall; and a receiving space therein; battery racks comprising a first battery rack group and a second battery rack group positioned in the receiving space and spaced apart from each other while facing each other with reference to a center of the receiving space, and wherein the battery racks of the first battery rack group are spaced apart from the second sidewall by a certain distance and disposed in parallel along a first direction, the battery racks of the second battery rack group are spaced apart from the fourth sidewall by a certain distance and disposed in parallel along the first direction; an upper duct positioned above the receiving space configured to supply cooling fluid to a cooling space which is a space between the first battery rack group and the second battery rack group; a cooling unit positioned outside the receiving space and configured to cool the cooling fluid; and a fluid moving member comprising a moving space where the cooling fluid heated after passing through the battery racks from the cooling space moves to the cooling unit, wherein the cooling unit is configured to be supplied with the heated cooling fluid from the moving space, cool the supplied cooling fluid, and then supply a resultant fluid to the upper duct. a chamber comprising a first sidewall; a second sidewall positioned perpendicularly to the first sidewall; a third sidewall facing the first sidewall and positioned perpendicularly to the second sidewall; and a fourth sidewall facing the second sidewall 120) and positioned perpendicularly to the first sidewall and the third sidewall; and a receiving space therein; battery racks comprising a first battery rack group and a second battery rack group positioned in the receiving space and spaced apart from each other while facing each other with reference to a center of the receiving space, and wherein the battery racks of the first battery rack group are spaced apart from the second sidewall by a certain distance and disposed in parallel along a first direction, the battery racks of the second battery rack group are spaced apart from the fourth sidewall by a certain distance and disposed in parallel along the first direction; an upper duct positioned above the receiving space configured to supply cooling fluid to a cooling space which is a space between the first battery rack group and the second battery rack group; a cooling unit positioned outside the receiving space and configured to cool the cooling fluid; and a fluid moving member comprising a moving space where the cooling fluid heated after passing through the battery racks from the cooling space moves to the cooling unit, wherein the cooling unit is configured to be supplied with the heated cooling fluid from the moving space, cool the supplied cooling fluid, and then supply a resultant fluid to the upper duct.