Modified cobalt-free lithium-rich manganese-based positive electrode material and preparation method thereof

The invention discloses a modified cobalt-free lithium-rich manganese-based positive electrode material and a preparation method thereof, and belongs to the technical field of modification of cobalt-free lithium-rich manganese-based positive electrode materials. According to the technical scheme, the modified cobalt-free lithium-rich manganese-based positive electrode material comprises a cobalt-free lithium-rich manganese-based positive electrode material, and divalent tin ions are dispersed in a bulk phase of the cobalt-free lithium-rich manganese-based positive electrode material. The divalent tin ions are doped in the bulk phase of the cobalt-free lithium-rich manganese-based positive electrode material, the positive electrode material is modified, and compared with an unmodified cobalt-free lithium-rich manganese-based positive electrode material, the electrochemical performance of an assembled battery is more excellent. 本发明公开了一种改性无钴富锂锰基正极材料及其制备方法，属于无钴富锂锰基正极材料的改性技术领域。其技术方案为：所述改性无钴富锂锰基正极材料包括无钴富锂锰基正极材料，无钴富