Positive electrode having specified elongation for improving safety and secondary battery including the same
View Patent ↗The present disclosure relates to an electrode having improved safety and a secondary battery including the same. It is possible to prevent or significantly reduce an internal short-circuit between a positive electrode current collector and a negative electrode current collector and an internal short-circuit between a positive electrode current collector and a negative electrode active material layer, caused by nail penetration, by controlling the elongation of a positive electrode to 0.6-1.5%.
1. A positive electrode for a secondary battery, comprising:
a positive electrode current collector; and
a positive electrode active material disposed on at least one surface of the positive electrode current collector,
wherein the positive electrode has an elongation of 0.6-1.5%,
the elongation is measured in accordance with ISO527, and
wherein the elongation is an average elongation of an elongation in a machine direction and an elongation in a transverse direction.
2. The positive electrode for a secondary battery according to claim 1 , wherein the positive electrode current collector has a thickness of 6-20 μm.
3. The positive electrode for a secondary battery according to claim 1 , wherein the positive electrode current collector is aluminum foil.
4. The positive electrode for a secondary battery according to claim 1 , wherein the positive electrode active material has an average particle diameter of 4-12 μm.
5. The positive electrode for a secondary battery according to claim 1 , wherein the positive electrode active material layer has a porosity of 23-35% after rolling.
6. A secondary battery comprising the positive electrode as defined in claim 1 , a negative electrode and a separator interposed between the positive electrode and the negative electrode.