近年来,研究过渡金属磷酸盐结晶功能材料,特别是具有光、电、磁及催化等特性的材料,已成为热点领域。其中,磷酸钴锂是商业化锂离子蓄电池中常用的正极材料,其晶体结构呈现有序的橄榄石型结构,属于正交晶系。
应用磷酸钴锂表现出非常稳定的锂离子脱嵌行为。作为LiCoPO₄正极材料,它的理论放电比容量高达167mAh/g,相对于锂的电极电势为4.8V,有望成为新一代高容量、高电压的正极材料。
High-quality thin films of cathode material LiCoPO4 are analyzed using a combination of STEM-EELS, XRD, and atomistic simulations. Capacity fade during cycling is accompanied by formation of large numbers of cation exchange defects, especially at surfaces, blocking the preferred Li-ion migration pathways.