The Li/CuS battery was a promising high-energy battery system because of the good electronic conductivity of 10³ S cm^-1 and a high theoretical capacity of 560 mAh g^-1 for CuS.^[1-3]In this paper, S/C/nano-Cu composite was prepared by a fast deposit method in an aqueous solution. Then the S/C/nano-Cu composite was dried at 60℃ in a vacuum oven for 24h and the CuS/C composite was further in situ formed in the process of drying.

CuS/C composite cathode for a lithium rechargeable battery is tested with 1 M LiFSI/DOL-DME as electrolyte at room temperature. The cathode undergoes a two-step reaction during the initial discharge to 1.5 V with a specific capacity of 546.6 mAh g^-1(see Figure 1a). Meanwhile, the composite also exhibits a good cycle behavior with 86.2% capacity retention after 30 cycles at 0.5 C (Figure 1b). These results suggest that the nano-size composite plays an important role during the charge-discharge process and the CuS/C composite is a promising cathode material for high-energy lithium secondary battery.

Figure 1. (a) Initial charge-discharge curves of the CuS/C composite cathode; (b) cycle performance of the CuS/C composite cathode at 0.5 C.

Acknowledgements

This work is supported by Shanghai Science and Technology Committee Rising-Star Program (15QB1402000).

 

Reference

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[2] J.S. Chung, H.J. Sohn, J. Power Sources 108 (2002) 226.

[3] Y.R. Wang, X.W.Zhang, P.Chen, H.T.Liao, S.Q.Cheng, Electrochimica Acta 80 (2012) 264.