CYLINDRICAL LITHIUM ION SECONDARY BATTERY AND MANUFACTURING METHOD THEREFOR

摘要

This cylindrical lithium ion secondary battery has a rolled electrode body and a non-aqueous electrolyte that are placed inside a cylindrical external can with a closed end, said rolled electrode body created by laminating a positive electrode and a negative electrode together via a separator and rolling the laminate into a spiral shape. The cylindrical lithium ion secondary battery is characterized in that the negative electrode has two or more collector tabs, some of the aforementioned two or more tabs are made of copper, the aforementioned two or more tabs are integrally joined by means of welding, the aforementioned integrally joined body comprising the two or more collector tabs is welded to the bottom inner surface of the aforementioned can, and a copper alloy is present at the positions where the aforementioned two or more collector tabs are welded.