High-rate LiFe0.75Mn0.25PO4/C cathode material for lithium-ion battery was prepared by oriented growth of precursor crystal plane

Abstract

The emergence of the lithium-ion battery as a subject of intense research interest has propelled of high-energy–density LiFe_xMn_1-xPO₄(LFMP) becoming a prominent area of investigation. However, the material suffers from inherently low electronic conductivity due to its olivine structure, which imposes severe constraints on electron transport kinetics, thus adversely impacting both charge–discharge rates and overall electrochemical performance. We propose an innovative protocol for high-precision reaction mechanism modulation. By employing Fe₃(PO₄)₂·8H₂O with strategically enhanced (020) crystal plane exposure as a pivotal precursor, we synthesized LiFe_0.75Mn_0.25PO₄/C cathode material featuring a shorter ion diffusion path. Comprehensive characterization coupled with electrochemical validation revealed that the resultant cathode material exhibits a smaller particle size and more uniform morphology, along with a superior rate performance and cycle stability. The discharge specific capacity is 144.1 mAh g⁻¹ and the capacity retention reaches 96.1 % over 1000 cycles at a 1C rate. The findings demonstrate that the regulation of the growth trajectory of the precursor Fe₃(PO₄)₂·8H₂O crystal plane can markedly enhance the electronic conductivity and Li⁺ mobility of the cathode material, thereby optimising the electrochemical performance.