The structural stability of LiCoO₂ at high voltage is a crucial concern of LiCoO₂ electrode. The experiment in this work have proved that mixed LiCoO₂ and LiFePO₄ electrode can stabilize the layered structure of LiCoO₂ and improve their cycle stability significantly. The SEM images show that a protective thin film was gradually formed on the surface of LiCoO₂ particles during charging and discharging. With the amount of mixed LiFePO₄ increasing, the film increases, which inhibits the broken of the LiCoO₂ particles and the formation of Co₃O₄; The battery built using the mixed LiCoO₂ and LiFePO₄ electrodes shows the best cycle stability when the content of LiFePO₄ is 12 wt%, with the initial discharge specific capacity of 177.9 mA h g⁻¹ and the capacity retention of 77.2% after 200 cycles between 3.0 and 4.5 V at 0.2 C.

LiCoO ₂在高压下的结构稳定性是LiCoO ₂电极的关键问题。实验证明，混合LiCoO ₂和LiFePO ₄电极可以稳定LiCoO ₂的层状结构，并显着提高其循环稳定性。SEM图像显示在充电和放电期间在LiCoO ₂颗粒的表面上逐渐形成保护薄膜。随着LiFePO ₄的混合量增加，膜增加，这抑制了LiCoO ₂颗粒的破裂和Co ₃ O ₄的形成。使用混合LiCoO制成的电池当LiFePO ₄的含量为12  wt％时，图₂和LiFePO ₄电极表现出最佳的循环稳定性，初始放电比容量为177.9 mA h g ^-1，在3.0和4.5 V在0.2 V下进行200次循环后的容量保持率为77.2％ C。