Electrochemical Study of K⁺-Doped LiNi_0.5Co_0.2Mn_0.3O₂ Prepared by Co-Precipitation Freeze-Drying Method

LiNi_0.5Co_0.2Mn_0.3O₂ lithium-ion battery cathode material is considered to be one of the most promising cathode materials for development. The co-precipitation-freeze-drying method was used to add K⁺ to the materials to investigate the changes in the microstructure as well as the electrochemical properties of the materials. Specifically, K⁺-doped LiNi_0.5Co_0.2Mn_0.3O₂ cathode materials were successfully synthesized by the co-precipitation-freeze-drying method, and the prepared Li \(_{{1 - x}}\) K_xNi_0.5Co_0.2Mn_0.3O₂ materials were well-distributed and exhibited excellent electrochemical properties. Providing an initial discharge capacity of 189.26 mA h g^–1 capacity retention of 66.66%, 100 cycles of 2.5–4.8 V and a current density of 0.1 C. The good electrochemical performance of the material may be attributed to the increased lattice spacing of the material with the addition of K⁺, which enlarges the channels for lithium ion insertion and detachment, further accelerating its diffusion rate.