LITHIUM SECONDARY BATTERY

PROBLEM TO BE SOLVED: To provide a lithium secondary battery with improved sealing. SOLUTION: An upper case 31a and a lower case 31b which construct a case 31 of a lithium secondary battery are each constructed by accumulating an internal polymer layer, an aluminum layer and an external polymer layer, one by one. A battery assembly 35 is inserted in an internal space of the case 31, and is constructed by accumulating an anode, a separator and a cathode one by one. An anode tab 36a is led from an end of the anode, and a cathode tab 36b is led from an end of the cathode. An anode terminal 37 is formed on the upper case 31a and is electrically connected with the anode tab 36a, and a terminal cathode 38 is formed on the lower case 31b and is electrically connected with the cathode tab 36b. At this time, each of the anode terminal 37 and the terminal cathode 38 is an aluminum layer whose surface is exposed outside by partly removing the external polymer layer of each of the upper case 31a and the lower case 31, and is electrically connected with each of the anode the cathode by partially removing the internal polymer layer and connecting each of the anode tab 36a and the cathode tab 36b with the aluminum layer whose surface is exposed internally.