Enhancing lithium-ion and electric conductive Li2FeSiO4 cathode through in situ boron-doping and carbon-coating strategy

The extremely low electrical conductivity and ion-diffusion coefficient of Li 2 FeSiO 4 limits its application as a cathode material in lithium-ion batteries. Therefore, in situ boron-doped Li 2 FeSi 1− x B x O 4− δ /C ( x  = 0, 0.01, 0.03, 0.05 and 0.07) at the Si site was prepared via the solid-state reaction method using pitch as the carbon source. B doping in the lattice structure and a carbon coating on the surface of the composites could effectively enhance the Li + /electron conductivity. Moreover, the reduced particle size of the active material with the relatively high specific area via boron-doped modification could improve the wettability between the electrolyte and cathode. With the synergistic effect of appropriate boron doping and carbon coating, it exhibits a good rate performance, specific capacity, and cycling performance. As a result, the as-prepared Li 2 FeSi 0.95 B 0.05 O 4− δ /C cathode showed a high discharge capacity of 160.7 mAh·g −1 at 0.2C, and the capacity retention rate was 96% after 100 cycles at 1.0C. This work presents an effective path for designing advanced cathode materials for lithium-ion batteries. Graphical abstract