公开(公告)号：EP3955338A1

公开(公告)日：2022-02-16

申请号：EP21190525.2

申请日：2021-08-10

Applicant: BYD Company Limited

Inventor： CHEN, Na ,  RUAN, Zewen ,  ZHU, Yan ,  HAO, Rong ,  PAN, Yi

IPC: H01M4/131

Abstract: The present invention discloses a composite cathode material, a cathode plate and a preparation method thereof, and a battery. The composite cathode material comprises a ternary material and a phase-transition material. The phase-transition material undergoes phase transition in the charge/discharge interval of the ternary material. The ternary material has a single crystal structure, the phase-transition material has a single crystal structure or a poly-crystalline structure, and the phase-transition material is coated on the surface of the ternary material. The weight ratio of the ternary material to the phase-transition material is 80:20-99.8:0.2. The ternary material has a nanohardness of 0.001-5 Gpa, and the phase-transition material has a nanohardness of 0.01-10 GPa. According to the embodiment of the present invention, the cycle performance of the battery is improved, the impedance increase of the material during the aging process is reduced, and the safety of the battery is improved.