In situ formed three-dimensional (3D) lithium–boron (Li–B) alloy as a potential anode for next-generation lithium batteries

The practical application of the lithium anode in lithium metal batteries (LMBs) has been hindered by the uncontrollable growth of lithium dendrite and the high volumetric change during cycling. Herein, the in situ formed three-dimensional (3D) lithium–boron (Li–B) alloy is suggested as an excellent alternative to the Li metal, in which the 3D LiB skeleton can mitigate the growth of Li dendrites and volumetric change. In this study, the Li–B alloy anodes with different B contents were manufactured by high-temperature melting. It was found that the boron content had a significant effect on the electrochemical performance of the Li–B alloy. The Li–B alloy with the least B content (10 wt%, 10LiB) demonstrated the lowest overpotential of 0.0852 V after 300 h and the lowest interface resistance. However, the full cell with 15LiB as the anode displayed the best cycling performance of 115 mAh·g−1 after 100 cycles with a columbic efficiency greater than 97%. The obtained results suggest that the in situ formed three-dimensional Li–B alloy anode can be an excellent alternative to the Li anode via tuning B contents for next-generation high energy density LMBs.