An electrochemical battery comprising: a battery module comprising at least one electrochemical cell; an air supplier configured to supply air to the battery module and maintain an oxygen concentration in the air that is supplied to the battery module, the air supplier comprising an air suction device configured to suction air from the outside, and an oxygen generator; an air recirculator configured to recirculate air exhausted from the battery module; and a controller configured to control the air supplier and the air recirculator, and wherein the controller is configured to maintain the oxygen concentration in the air supplied to the battery module, wherein the battery module comprises: an air inlet port through which air is introduced from the air supplier; and an air outlet port through which air remaining after a reaction in the at least one electrochemical cell is exhausted, and wherein the air recirculator is configured to recirculate the air exhausted through the air outlet port of the battery module to the air inlet port of the battery module, wherein the electrochemical battery is characterised in that the oxygen generator is configured to generate oxygen by separating oxygen from the suctioned air, and the air recirculator comprises an air flow passage connecting the air outlet port of the battery module and the oxygen generator such that mixed air of the air supplied through the air suction device and the air exhausted through the air outlet port of the battery module is supplied to the oxygen generator. a battery module comprising at least one electrochemical cell; an air supplier configured to supply air to the battery module and maintain an oxygen concentration in the air that is supplied to the battery module, the air supplier comprising an air suction device configured to suction air from the outside, and an oxygen generator; an air recirculator configured to recirculate air exhausted from the battery module; and a controller configured to control the air supplier and the air recirculator, and wherein the controller is configured to maintain the oxygen concentration in the air supplied to the battery module, wherein the battery module comprises: an air inlet port through which air is introduced from the air supplier; and an air outlet port through which air remaining after a reaction in the at least one electrochemical cell is exhausted, and an air inlet port through which air is introduced from the air supplier; and an air outlet port through which air remaining after a reaction in the at least one electrochemical cell is exhausted, and wherein the air recirculator is configured to recirculate the air exhausted through the air outlet port of the battery module to the air inlet port of the battery module, wherein the electrochemical battery is characterised in that the oxygen generator is configured to generate oxygen by separating oxygen from the suctioned air, and the air recirculator comprises an air flow passage connecting the air outlet port of the battery module and the oxygen generator such that mixed air of the air supplied through the air suction device and the air exhausted through the air outlet port of the battery module is supplied to the oxygen generator.