Abstract：Magnesium batteries with the advantages of low cost, high energy density and high safety are expected to be applied in large-scale energy storage and power vehicles in the future. However, magnesium batteries are still in the early development, and cathode is the key reason that limits the battery performance. The high charge density of Mg2+ results in slow diffusion of Mg2+ in cathode materials. Therefore, how to improve the electrochemical performance of cathode materials is the focus and difficulty in the field of magnesium batteries. By analysing the related researches, six strategies for improving the electrochemical performance of cathode materials were summarized in this paper, namely, reducing the particle size, using the shielding effect of the solvent, increasing the interlayer distance, regulating anions, exploring new structures and developing double ion batteries. By clarifying the root cause that makes the strategies effective and pointing out the advantages and limitations of the strategies, this paper provides valuable guidance for the development of high-performance cathode materials for magnesium batteries. Finally, the development status of magnesium battery cathode materials was summarized, and the future development trend of cathode and the whole battery system was prospected.
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