Enhancing the electrochemical performance of LiMn0.6Fe0.4PO4 with binary conductive agent of super P and hollow carbon nanosphere

LiMn_xFe_1-xPO₄ (LMFP) is regarded as an ideal next-generation cathode material for lithium-ion batteries (LIBs) due to the excellent energy density, high safety and low cost. However, the poor electrical conductivity of LMFP has become an urgent problem in the way to be the electrode materials of LIBs. In this paper, the hollow carbon nanospheres (HCN) is compounded with Super P(SP), Acetylene Black(AB) and Ketjen Black(KB) to construct the binary conductive agent, respectively. Particle gradation of SP and HCN as binary conductive agent fills the empty space between HCN, LMFP, and the collector, which improves electron transfer between active substance, and further reduces the charge transfer impedance. Specifically, the LMFP electrode with SP-HCN binary conductive agent exhibits excellent electrochemical performance with the high specific capacity of 150.9 mAh·g⁻¹ at 0.1 C and 130.8 mAh·g⁻¹ with a capacity retention of 93.67% after 200 cycles at 1 C. Compared to the sample without HCN, the capacity is improved by 10–20 mAh·g⁻¹, the Li⁺ diffusion coefficient is improved by one order of magnitude to 1.03$\times$10⁻¹², and the electrochemical transfer impedance is reduced from 269.91 to 90.92. The finding shows that the SP-HCN binary conductive agent significantly enhances LMFP battery performance.