公开(公告)号：US20210313563A1

公开(公告)日：2021-10-07

申请号：US16964746

申请日：2020-05-22

Applicant: NINGDE AMPEREX TECHNOLOGY LIMITED

Inventor： Feilong GUO ,  Juan JIN ,  Xinbing CHEN ,  Hongming YU

IPC: H01M4/36 ,  H01M4/505 ,  H01M4/525 ,  H01M4/131 ,  H01M10/0525

Abstract: The present application relates to a cathode and an electrochemical device. The cathode comprises: a cathode current collector; and a cathode active material layer disposed on a surface of the cathode current collector, wherein the cathode active material layer comprises a first particle and a second particle, the first particle comprising a secondary particle composed of a third particle, the third particle being a primary particle, the first particle having an average particle size of 5 μm to 20 μm, the third particle having an average particle size of 200 nm to 700 nm, the second particle comprising a fourth particle and/or a secondary particle composed of the fourth particle, the fourth particle being a primary particle, the second particle having an average particle size of 3 μm to 5 μm, the fourth particle having an average particle size of 800 nm to 5 μm, the first particle being contained in a region close to the cathode current collector, and the second particle being contained in a region away from the cathode current collector. The cathode can significantly improve the rate performance, cycle performance and safety performance of the electrochemical device.