FLAT TYPE SECONDARY BATTERY

PROBLEM TO BE SOLVED: To provide a flat type secondary battery of high capacity, with excellent reliability, in which fixing means for fixing an electrode group is simplified to decrease the number of manufacturing steps.SOLUTION: A flat type secondary battery 1 includes a positive electrode plate 20 and a negative electrode plate 30 which are band-like electrode plates in which an active material layer is formed on a surface, with a separator interposed between the positive electrode plate 20 and the negative electrode plate 30, contained in a metal case 2 together with electrolyte, and contains an electrode group 10 in which the positive electrode plate 20 and the negative electrode plate 30 are folded to form a predetermined area in top view. The positive electrode plate 20 has a connection tab part 21 for connection to the metal case 2 at an end part. There are provided a folding back part 21a at which the connection tab part 21 of the positive electrode plate 20 is folded back, and a fixing member 40 which covers a positive electrode plate end face 20a and a side surface of the electrode group 10, and fixes the positive electrode plate 20 and the negative electrode plate 30 so that they do not separate from each other. 【課題】電極群を固定する固定手段を簡素化して製造工数を低減し、信頼性に優れた高容量の扁平型二次電池を提供する。【解決手段】表面に活物質層が形成された帯形状の電極板である正極板２０及び負極板３０を有し、正極板２０と負極板３０との間にセパレータを介在させ、電解液と共に金属ケース２に内包し、平面視で所定の面積となるように正極板２０と負極板３０とを折りたたんでなる電極群１０を有する扁平型二次電池１であり、正極板２０は、端部に金属ケース２に接続する接続タブ部２１を有し、正極板２０の接続タブ部２１が折り返す折り返し部２１ａと、正極板端面２０ａと、電極群１０の側面とを覆い、正極板２０と負極板３０とが離間しないように固定する固定部材４０を設ける構成とした。【選択図】図１