LITHIUM REPLENISHING ADDITIVE FOR POSITIVE ELECTRODE AND PREPARATION METHOD THEREFOR, LITHIUM-RICH POSITIVE ELECTRODE, AND SECONDARY BATTERY

• Main Authors: KONG, Lingyong, ZHONG, Zeqin, WAN, Yuanxin
• Format: Patent
• Language: Chinese; English; French
• Published: 18.04.2024
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

A lithium replenishing additive for a positive electrode and a preparation method therefor, a lithium-rich positive electrode, and a secondary battery, which belong to the technical field of materials. The lithium replenishing additive for a positive electrode comprises: a lithium-rich iron-based material and a passivation material which is combined on the outer surface of the lithium-rich iron-based material in situ, wherein the chemical formula of the passivation material is aLi2OFexOy, where 1≤x≤3, 1≤y≤4, 0.0001≤a≤0.01, and 0.0001≤b≤0.01. The lithium-rich iron-based system in the lithium replenishing additive for a positive electrode has a relatively good lithium replenishing effect on a positive electrode material, and can compensate for the loss of lithium ions during the charging and discharging cycles of the material in a timely manner; in addition, the passivation material can effectively prevent the interface from reacting with ambient water and carbon dioxide to form excessive residual alkalis, impr