Synthesis of high-entropy perovskite metal fluoride anode materials for lithium-ion batteries via a one-pot solution method

The use of high-entropy perovskite metal fluoride anodes as pseudocapacitive electrode materials affords high specific capacity and high rate performance, however, current solvothermal methods limit large-scale production. In this study, we employed first principles calculations and thermodynamic analyses to successfully synthesize a new type of high-entropy perovskite lithium-ion battery anode material, K0.9(Mg0.2Mn0.2Co0.2Ni0.2Cu0.2)F2.9 (high-entropy perovskite metal fluoride, HEPMF), via a one-pot solution method, expanding the synthetic methods for high-entropy perovskite metal fluorides. The prepared HEPMF exhibited a single-phase cubic perovskite structure with high compositional uniformity. The electrochemical performance of HEPMF was assessed, revealing that crystal transitions induced the long-term activation process during charge-discharge cycling. Additionally, HEPMF exhibited high rate performance with a specific capacity of 698-311 mAh g-1 at current densities of 0.1-3.2 A g-1. The enhanced rate performance was attributed to its higher vacancy defect density compared to those of low- and medium-entropy perovskite fluorides, which increases the specific surface area and ion diffusion channels. Furthermore, a full battery employing HEPMF as an anode and commercial LiNi0.6Co0.2Mn0.2O2 (NCM622) as a cathode exhibited superior electrochemical performances with promising application prospects. These findings underscore the significant potential of HEPMF as a high-rate and long-life anode material for LIBs.