Modified positive electrode active material, preparation method therefor and electrochemical energy storage device

Abstract

The present disclosure provides a modified positive electrode active material. The modified positive electrode active material comprises a positive electrode active material inner core; a metal oxide layer comprising a metal oxide and coated on a surface of the positive electrode active material inner core; and a polymer layer comprising a polymer and coated on a surface of the metal oxide layer, the polymer being one or more selected from a group consisting of polyacrylic acid, polymethyl methacrylate, polyacrylamide and lithium polyacrylate. The modified positive electrode active material of the present disclosure has better structure stability and thermal stability, when the modified positive electrode active material is applied in the electrochemical energy storage device, cycle performance and safety performance of the electrochemical energy storage device can be significantly improved without decreasing energy density of the electrochemical energy storage device.

Dependencies are inferred from the claim text.