Investigation of CrSi2 and MoSi2 as anode materials for lithium-ion batteries

We report on the suitability of the two metal silicides MoSi2 and CrSi2 as anode materials for Li-ion batteries. The two materials were synthesized by high energy ball milling of the corresponding metals and X-ray diffraction was used to follow the evolution/formation of the crystalline phases. The in-house prepared powders have shown better battery performance than commercial powders (as-received or ball-milled). We observed that 20 h were necessary for the formation of MoSi2 whereas 100 h were needed for the formation of the CrSi2 powder. The best battery performance was obtained with the synthesized CrSi2 powder that has a theoretical capacity value of 469 mAh g−1. This powder provided capacities of 340, 262, 167, 110, and 58 mAh g−1 at C/12, C/6, C/2, C, and 2C, respectively. Cycling at 60 °C showed higher capacity values, but with a faster fade of these values.

► CrSi2 and MoSi2 were investigated as anode materials for lithium-ion batteries. ► High energy ball milling synthesis of CrSi2 and MoSi2 was performed. ► CrSi2 gave capacity of 340 mAh g−1 at C/12 that decreased at higher C-rate. ► Cycling at 60 °C showed higher capacity but with rapid fade upon cycling.