A battery comprising: a cell having an electrode laminate and a liquid electrolyte mounted in an internal space of a battery case; a gas discharging member communicating with the internal space of the battery case for discharging gas generated in the cell out of the cell; and a liquid electrolyte injection member communicating with the internal space of the battery case for injecting a liquid electrolyte into internal space of the battery case, and wherein the gas discharging member comprises a pipe member communicating with the internal space of the battery case, wherein the gas discharging member further comprises a suction member mounted at the other end of the pipe member, wherein the suction member is a suction pump, wherein the liquid electrolyte injection member comprises a pipe member communicating with the internal space of the battery case and a liquid electrolyte storage tank mounted at one end of the pipe member, wherein the cell is a pouch-shaped lithium secondary cell comprising a space portion having an electrode laminate and an electrolyte mounted therein and a sealed portion surrounding the space portion, the sealed portion being provided with through holes coupled to the pipe member of the liquid electrolyte injection member and the pipe member of the gas discharging member, and wherein the liquid electrolyte injection member further comprises a backward flow prevention member mounted at the other end of the pipe member, characterized in that the gas discharging member comprises a liquid material non-transmissive porous film mounted at one end of the pipe member and that the backward flow prevention member is a check valve for preventing the liquid electrolyte from flowing backward from the cell to the liquid electrolyte storage tank, wherein the check valve comprises a center pin; a first membrane fixedly coupled to the pipe member, the first membrane being provided with a hollow portion, through which the center pin extends, and a through hole, through which the liquid electrolyte is injected; a second membrane coupled to one end of the center pin, the second membrane being coupled to or separated from the first membrane for opening and closing the pipe member; and an elastic member for maintaining a coupling state between the first membrane and the second membrane. a cell having an electrode laminate and a liquid electrolyte mounted in an internal space of a battery case; a gas discharging member communicating with the internal space of the battery case for discharging gas generated in the cell out of the cell; and a liquid electrolyte injection member communicating with the internal space of the battery case for injecting a liquid electrolyte into internal space of the battery case, and wherein the gas discharging member comprises a pipe member communicating with the internal space of the battery case, wherein the gas discharging member further comprises a suction member mounted at the other end of the pipe member, wherein the suction member is a suction pump, wherein the liquid electrolyte injection member comprises a pipe member communicating with the internal space of the battery case and a liquid electrolyte storage tank mounted at one end of the pipe member, wherein the cell is a pouch-shaped lithium secondary cell comprising a space portion having an electrode laminate and an electrolyte mounted therein and a sealed portion surrounding the space portion, the sealed portion being provided with through holes coupled to the pipe member of the liquid electrolyte injection member and the pipe member of the gas discharging member, and wherein the liquid electrolyte injection member further comprises a backward flow prevention member mounted at the other end of the pipe member, characterized in that the gas discharging member comprises a liquid material non-transmissive porous film mounted at one end of the pipe member and that the backward flow prevention member is a check valve for preventing the liquid electrolyte from flowing backward from the cell to the liquid electrolyte storage tank, wherein the check valve comprises a center pin; a first membrane fixedly coupled to the pipe member, the first membrane being provided with a hollow portion, through which the center pin extends, and a through hole, through which the liquid electrolyte is injected; a second membrane coupled to one end of the center pin, the second membrane being coupled to or separated from the first membrane for opening and closing the pipe member; and an elastic member for maintaining a coupling state between the first membrane and the second membrane.