Highly efficient & stable Bi & Sb anodes using lithium borohydride as solid electrolyte in Li-ion batteries

Abstract

Herein, we employed Bi and Sb as the negative electrode in all solid-state lithium-ion batteries (LIBs) using LiBH₄ as the solid-state electrolyte. The composite anode materials with acetylene black (AB) and LiBH₄, prepared by high energy ball-milling, have shown extremely high stability with a high coulombic efficiency of 90-99% over a number of cycles. The gravimetric capacity decayed by only 18 and 5% as compared to the initial volumetric capacity of 4681.7 and 4393.4 mA h cm^-3 for Bi and Sb anodes respectively.

Fig. 1. Cyclic voltammograms of Bi and Sb composite electrode scanned at 0.1 mV s⁻¹.

Fig. 2. The first galvanostatic discharge–charge curves for (a) Bi–LiBH₄–AB composite (b) Sb–LiBH₄–AB composite electrodes in the voltage range of 0.2–1.5 V at 0.1C.

Fig. 3. (a) The cyclic galvanostatic discharge–charge profiles for Bi–LiBH₄–AB composite electrodes in the voltage range of 0.2–1.5 V at 0.1C. Only selected cycles (1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100) are shown for clear visibility. (b) Cyclic stability of Bi–LiBH₄–AB composite electrodes as shown by discharge/charge capacity and the coulombic efficiency vs. cycle no.

Fig. 4. (a) The cyclic galvanostatic discharge–charge profiles for Sb–LiBH₄–AB composite electrodes in the voltage range of 0.2–1.5 V at 0.1C. Only selected cycles (1, 5, 10, 20, 30, 40, 50) are shown for clear visibility. (b) Cyclic stability of Sb–LiBH₄–AB composite electrodes as shown by discharge/charge capacity and the coulombic efficiency vs. cycle no.