Structural regulation and lithium storage performance of SEG/Fe/Mo/C anode materials for lithium-ion batteries

Lithium-ion batteries (LIBs) are promising for new energy applications due to their high energy density and long cycle life. Anode materials composed of in-house synthesized micro-expanded graphite (SEG) and Fe₃O₄ exhibit high specific discharge capacity and rate capability. To further improve the lithium storage capacity, a composite of MoO₃/C and SEG/Fe₃O₄ was prepared by a water bath method followed by heat treatment, with self-made slightly expanded microcrystalline graphite (SEG)/Fe₃O₄ as the raw material. The results show that the composite, with SEG as the matrix and the synergistic effect of Fe₃O₄, MoO₃, and conductive carbon particles, exhibits significantly improved lithium storage performance. At a current density of 0.1 A·g −1 , it delivers an initial specific discharge capacity of 1157.6 mAh·g −1 with an initial Coulombic efficiency of 81.06%, and retains a specific discharge capacity of 853.2 mAh·g −1 after 100 cycles. This is mainly attributed to the larger interlayer spacing and pore volume of SEG/Fe/Mo/C, which provide abundant adsorption sites for lithium ions. Meanwhile, the lower charge transfer impedance facilitates the diffusion of lithium ions between the graphite layers. This study provides valuable insights and an effective strategy for developing high-performance LIB anode materials.