Nickel-copper-iron-manganese precursor, preparation method and washing method thereof, positive electrode material and battery

The invention relates to the technical field of preparation of positive electrode materials, and discloses a nickel-copper-iron-manganese precursor, a preparation method and a washing method thereof, a positive electrode material and a battery. The washing method disclosed by the invention comprises the following steps: mixing an unwashed nickel-copper-iron-manganese precursor with a sodium bicarbonate solution, fully diffusing sulfur in the precursor into the solution, and performing solid-liquid separation to obtain a desulphurized precursor; and mixing the desulphurized precursor with pure water, so that sodium in the precursor is fully diffused into the solution, and then carrying out solid-liquid separation. The preparation method disclosed by the invention comprises the washing method. The nickel-copper-iron-manganese precursor disclosed by the invention is prepared by adopting the preparation method. The positive electrode material disclosed by the invention is prepared from the precursor. According to