An electrochemical device comprising: an electrode assembly in which a length direction, a thickness direction, and a width direction are defined; and a packing member in which the electrode assembly is disposed, wherein the packing member comprises: a first packing film comprising a first gas barrier layer and a first sealing layer; and a second packing film comprising a second gas barrier layer and a second sealing layer, wherein the packing member further comprises: an accommodation portion in which the electrode assembly is disposed between the first packing film and the second packing film; and a bonded portion (120, 130) in which an edge of the first packing film and an edge of the second packing film are bonded to each other, wherein the bonded portion comprises a first gas barrier rim portion extending in the length direction, wherein the first gas barrier rim portion comprises: a first bonded sealing layer, in which a first area of the first sealing layer is bonded to a first area of the second sealing layer; and a third gas barrier layer contacting the first bonded sealing layer, wherein the third gas barrier layer comprises: a bottom portion and an upper portion parallel to the first bonded sealing layer and disposed at different heights from each other; and a middle portion continuously extending between the bottom portion and the upper portion and surrounding an end of the first bonded sealing layer in the width direction; and wherein the first gas barrier rim portion is bendable around an axis of the width direction in a region in the length direction; characterized in that the electrochemical device comprises at least two accommodation portions disposed apart from one another in the length direction, at least two electrode assemblies disposed in the at least accommodation portions, respectively, and at least one connection portion connecting the at least two accommodation portions and wherein the electrochemical device further comprises a first conductive line and a second conductive line extending through an inner portion of the at least one connection portion to electrically connect the electrode assemblies disposed in the at least two accommodation portions, respectively, with one another. an electrode assembly in which a length direction, a thickness direction, and a width direction are defined; and a packing member in which the electrode assembly is disposed, wherein the packing member comprises: a first packing film comprising a first gas barrier layer and a first sealing layer; and a second packing film comprising a second gas barrier layer and a second sealing layer, a first packing film comprising a first gas barrier layer and a first sealing layer; and a second packing film comprising a second gas barrier layer and a second sealing layer, wherein the packing member further comprises: an accommodation portion in which the electrode assembly is disposed between the first packing film and the second packing film; and a bonded portion (120, 130) in which an edge of the first packing film and an edge of the second packing film are bonded to each other, an accommodation portion in which the electrode assembly is disposed between the first packing film and the second packing film; and a bonded portion (120, 130) in which an edge of the first packing film and an edge of the second packing film are bonded to each other, wherein the bonded portion comprises a first gas barrier rim portion extending in the length direction, wherein the first gas barrier rim portion comprises: a first bonded sealing layer, in which a first area of the first sealing layer is bonded to a first area of the second sealing layer; and a third gas barrier layer contacting the first bonded sealing layer, a first bonded sealing layer, in which a first area of the first sealing layer is bonded to a first area of the second sealing layer; and a third gas barrier layer contacting the first bonded sealing layer, wherein the third gas barrier layer comprises: a bottom portion and an upper portion parallel to the first bonded sealing layer and disposed at different heights from each other; and a middle portion continuously extending between the bottom portion and the upper portion and surrounding an end of the first bonded sealing layer in the width direction; and wherein the first gas barrier rim portion is bendable around an axis of the width direction in a region in the length direction; characterized in that the electrochemical device comprises at least two accommodation portions disposed apart from one another in the length direction, at least two electrode assemblies disposed in the at least accommodation portions, respectively, and at least one connection portion connecting the at least two accommodation portions and wherein the electrochemical device further comprises a first conductive line and a second conductive line extending through an inner portion of the at least one connection portion to electrically connect the electrode assemblies disposed in the at least two accommodation portions, respectively, with one another.