BATTERY ASSEMBLY

The battery assembly (1) includes a bus bar (81) for electrically connecting the battery or cell units (30) each other by connecting electrode members (44,45) each being provided with the battery or cell unit (30) associated. The battery assembly (1) further includes a bus bar extension portion (82) extended from the bus bar (81). The bus-bar extension portion (82) is disposed out of the area between the adjacent electrode members (Tb, Tb) and provided with a temperature sensing or detection element (90 that detects the temperature of the battery or cell unit (30).