Cobalt (II) fluoride begins to enter into the horizons of people along with the research upsurge of metal fluorides. It is very significative and theoretically influential to make certain its electrochemical reaction mechanism. In this work, we discover a new and unrevealed reversible interfacial intercalation mechanism reacting below 1.2 V for cobalt (II) fluoride electrode material, which contributes a combined discharge capacity of about 400 mA h g⁻¹ with the formation of SEI film at the initial discharge process. A highly reversible storage capacity of 120 mA h g⁻¹ is observed when the cell is cycled over the voltage of 0.01-1.2 V at 0.2 C, and the low-potential voltage reaction process has a significant impact for the whole electrochemical process. Electrochemical analyses suggest that pure cobalt (II) fluoride shows better electrochemical performance when it is cycled at 3.2-0.01 V compared to the high range (1.0-4.5 V). So, we hold that cobalt (II) fluoride is more suitable to serve as anode material for lithium ion batteries. In addition, we also try to reveal the relevant performance and reaction mechanism, and realize the possibility of cobalt (II) fluoride as anode material for sodium ion batteries.

随着金属氟化物的研究热潮，氟化钴（II）开始进入人们的视野。确定其电化学反应机理是非常有意义的，并且在理论上具有影响力。在这项工作中，我们发现了一种新的且未公开的可逆界面插入机制，对于氟化钴（II）电极材料，其在1.2 V以下反应，在首次放电时形成SEI膜时贡献了约400 mA h g ^-1的组合放电容量过程。120 mA h g ^-1的高度可逆存储容量当电池在0.2 C下在0.01-1.2 V的电压下循环时，可以观察到这种现象，低电位电压反应过程对整个电化学过程都有重要影响。电化学分析表明，与高量程（1.0-4.5 V）相比，纯氟化钴（II）在3.2-0.01 V循环时显示出更好的电化学性能。因此，我们认为氟化钴（II）更适合用作锂离子电池的负极材料。此外，我们还试图揭示相关的性能和反应机理，并认识到氟化钴（II）可用作钠离子电池负极材料的可能性。