| 摘要 |
PURPOSE: A secondary battery is provided to reduce the resistance of positive electrode current collector and negative electrode current collector, to increase capacity and output power, and improve the power properties of a secondary battery. CONSTITUTION: A secondary battery(100) comprises an electrode group(10) including a positive electrode(12) and a negative electrode(13), and a case(20) accepting electrolyte liquid and the electrode group. The positive electrode comprises a current collector in which positive electrode active material layer is spread, the negative electrode comprises a current collector in which negative electrode active material layer is spread. At least one among the positive electrode current collector and the negative electrode current collector comprises a base layer and a protrusion, which is in one side of the base layer and has a thickness wider than the base layer. |
