SQUARE SECONDARY BATTERY

• Main Authors: YAMAMOTO YUKI, HORI NOBUYUKI
• Format: Patent
• Language: English; Japanese
• Published: 30.08.2018
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

PROBLEM TO BE SOLVED: To improve screening accuracy in aging, by forming a thick portion at a corresponding part, and utilizing the fact that the thick portion is compressed selectively when a battery is pressed with a prescribed pressure, in a cell where a metal extraneous material causes melting precipitation reaction at the mixture lamination part end of a wound electrode group, and internal short circuit occurs between the positive electrode and the negative electrode.SOLUTION: In a secondary cell including a wound electrode group formed by winding an electrode coated with a mixture layer and having a metal foil exposure part on one end side, a collector plate to be connected with the metal foil exposure part by welding, and a battery container for housing a collector plate and the wound electrode group, and having a pair of laterals facing the flat part of the wound electrode group, the portion where a content sandwiched by the pair of laterals becomes thickest in the battery container is placed along the weld zone of the collector plate, at a position facing the mixture layer lamination end on the metal foil exposure part side.SELECTED DRAWING: Figure 4 【課題】捲回電極群の合剤積層部端部で金属異物が溶解析出反応を起こし正極と負極間で内部短絡を有する電池において、該当部分に厚みが厚い部分を形成することで、電池を所定の圧力で押圧した際、厚みが厚い部分が選択的に加圧されることを利用して、エージング処理におけるスクリーニング精度を向上させる。【解決手段】合剤層が塗布され、一端側に金属箔露出部を有する電極を捲回した捲回電極群と、金属箔露出部と溶接により接続される集電板と、集電板と捲回電極群とを収納し、当該捲回電極群の平坦部と対向する一対の側面部を有する電池容器を備えた二次電池において、電池容器内部で一対の側面部に挟まれて配置される内容物の厚さが最も厚くなる部分は、集電板の溶接部に沿って配置され、かつ金属箔露出部側の合剤層積層端部と対向する位置に配置される。【選択図】図４