Battery cathode catalyst, preparation method thereof and application thereof in metal air battery

The invention provides a battery cathode catalyst. The battery cathode catalyst comprises porous cerium dioxide microspheres and silver powder, wherein the silver powder is dispersed in the cerium dioxide microspheres and on the surfaces of the cerium dioxide microspheres. In the battery cathode catalyst provided by the invention, the porous cerium dioxide microsphere is used as a stable silver carrier, the battery cathode catalyst has relatively large specific area, nanometer silver particles can be prevented from being agglomerated during the sintering and test process, so that the catalyst is maintained with relatively high catalytic activity; and moreover, cerium dioxide has favorable oxidization-reduction characteristic, oxygen can be consumed in an oxidization atmosphere and is provided in a reduction atmosphere, so that the oxygen is rapidly transferred to a three-phase interface in the cerium oxide, the oxygen migration rate is improved, and the energy efficiency of a battery is improved. 本发明提供了种电池阴极催