Surface protected lithium-metal-oxide electrodes

摘要

A lithium-metal-oxide positive electrode having a layered or spinel structure for a non-aqueous lithium electrochemical cell and battery is disclosed comprising electrode particles that are protected at the surface from undesirable effects, such as electrolyte oxidation, oxygen loss or dissolution by one or more lithium-metal-polyanionic compounds, such as a lithium-metal-phosphate or a lithium-metal-silicate material that can act as a solid electrolyte at or above the operating potential of the lithium-metal-oxide electrode. The surface protection significantly enhances the surface stability, rate capability and cycling stability of the lithium-metal-oxide electrodes, particularly when charged to high potentials.

主权项

1. A positive electrode for a non-aqueous lithium cell consisting of sol-gel coated lithium-metal-oxide particles, carbon, and a binder, the surface of the coated lithium-metal-oxide particles comprising a coating consisting of a lithium-metal-polyanionic material, wherein the general formula of the lithium-metal-polyanionic material consists of at least one lithium cation, at least one other metal cation, and at least one polyanion; the lithium-metal-polyanionic material is coated onto the surface of the lithium-metal-oxide particles from an acidic sol-gel solution; and wherein the lithium-metal-oxide particles comprise a composite oxide material comprising a Li2MnO3 component.