NONAQUEOUS ELECTROLYTE SECONDARY BATTERY AND METHOD FOR MANUFACTURING THE SAME

To provide a nonaqueous electrolyte secondary battery including a stacked electrode group that has a tab lead reduced in breakage, excessive nugget dents, and deformation around joints.SOLUTION: A nonaqueous electrolyte secondary battery includes a stacked electrode group 3 where a plurality of positive electrode plates 4 and a plurality of negative electrode plates 5 are stacked with a separator interposed between the respective positive and negative electrode plates. Each of the plurality of positive electrode plates 4 includes a positive electrode collector 41 having a positive electrode tab 43 in part. At least tip sides of a plurality of the positive electrode tab leads 43 are overlaid to each other to form a positive electrode tab lead overlaying part 44; a positive electrode terminal 7 is brought into contact with one surface of the positive electrode tab lead overlaying part 44; a nugget is provided on a surface of the positive electrode terminal 7; and the positive electrode terminal 7 is electrically joined with each of the positive electrode tab lead 43 of the positive electrode tab lead overlaying part 44 and the plurality of positive electrode tab leads 43 of the positive electrode tab lead overlaying part 44. Also in the negative electrode plates 5, the negative electrode tab leads are electrically joined as in the positive electrode plates 4.SELECTED DRAWING: Figure 3 【課題】破損、ナゲットの過度な凹み、接合部周辺の変形を軽減したタブリードを有する積層電極群を備える非水電解質二次電池を提供する。【解決手段】複数の正極板４と複数の負極板５の間にそれぞれセパレータを介在して積層した積層電極群３を備える。複数の正極板４は、それぞれ一部に正極タブリード４３を有する正極集電体４１を備える。複数の正極タブリード４３は少なくとも先端側を互いに重ね合せて正極タブリード重ね部４４とし、かつ正極タブリード重ね部４４の一方の面に正極端子７を当接させ、当該正極端子７の面にナゲットを設け、正極端子７と正極タブリード重ね部４４の正極タブリード４３、および正極タブリード重ね部４４の複数の正極タブリード４３を互いに電気的に接合する。負極板５についても、上記正極板４と同様に負極タブリードが電気的に接合されている。【選択図】図３