Composite material as well as preparation method and application thereof

The invention provides a composite material as well as a preparation method and application thereof. The composite material comprises noble metal and inert oxide, the surface of the noble metal is modified with functional groups, and the functional groups comprise hydroxyl and/or carboxyl. When the composite material is used for coating a positive active material, the direct-current internal resistance of the battery can be reduced, and the capacity performance of the material is effectively improved; and a uniform compound coating layer can be formed, so that direct contact between an active substance and an electrolyte is prevented, the interface stability can be improved to a certain extent, and the cycle performance of the material is improved. 本发明提供了一种复合物材料及其制备方法和应用，所述复合物材料中包括贵金属和惰性氧化物；所述贵金属的表面修饰有官能团，所述官能团包括羟基和/或羧基。采用本发明的复合物材料包覆正极活性物质，可降低电池的直流内阻，有效提高材料的容量性能；并能够形成均匀的复合物包覆层，阻止活性物质和电解液直接接触，在一定程度上可以改善界面稳定性，提高材料的循环性能。