Modified lithium supplement agent and preparation method and application thereof

The invention discloses a modified lithium supplement agent as well as a preparation method and application thereof, and relates to the technical field of lithium batteries. Metal elements such as Co, Cu, Ca, Ti, Zr, Al and Mg are doped/coated on the surface of a base material of the lithium supplementing agent, and the elements can inhibit the reaction decomposition of electrolyte on the lithium supplementing agent, so that the gas production rate is effectively reduced. After the lithium supplement agent is modified, the storage gas production rate of the battery can be remarkably reduced on the premise that the performance (such as battery capacity) of the battery is improved by a common lithium supplement agent. 本发明公开了一种改性补锂剂及其制备方法和应用，涉及锂电池技术领域。通过在补锂剂基材表面掺杂/包覆Co、Cu、Ca、Ti、Zr、Al、Mg等金属元素，这些元素能够抑制电解液对补锂剂的反应分解，有效地减少产气量。通过对补锂剂进行改性后，可以在保持普通补锂剂对电池性能(如电池容量)提升的前提下，显著降低电池的存储产气量。