Lithium secondary battery

A lithium secondary battery comprising:

• an electrode assembly to which an electrode tap is attached;
• an electrode tap receptor configured to house a portion of the electrode assembly;
• wherein the electrode tap receptor comprises a hole through which a portion of the electrode tap protrudes to an outside;
• and
• a case formed from one sheet configured to surround the electrode assembly,
• wherein an end of the electrode tap receptor and an end of the case partially overlap each other, and the end of the case is disposed over the end of the electrode tap receptor to seal the electrode assembly,
• wherein the case surrounds sides of the electrode assembly to which the electrode tap is not attached,
• wherein the electrode tap receptor includes a gas barrier layer,
• wherein the gas barrier layer includes at least one selected from a group consisting of ethylene-vinyl alcohol copolymer, polyvinylidene chloride, polyvinyl alcohol, nylon, polyamide, polyacrylonitrile, ionomer copolymer, a coating layer made of at least one selected from a group consisting of silica, alumina, rubber, glass and amorphous carbon, and a film having a coating layer in which layered silicate nano particles are dispersed in a polyvinyl alcohol binder,
• wherein the electrode tap receptor is formed in a plurality of layers, and the gas barrier layer is included in an inner layer of the electrode tap receptor, and
• wherein the gas barrier layer is formed on a portion of the electrode tap receptor which contacts the electrode assembly.