Three-dimensional Li-B alloy anode stabilized sulfide-based all-solid-state lithium batteries

Sulfide solid electrolytes are considered promising candidates for all-solid-state lithium batteries (ASSLBs) because of their high ionic conductivity and favorable mechanical properties. However, the uncontrolled growth of lithium dendrites at the lithium metal-electrolytes interface remains a major obstacle to their practical application. In this work, we introduced a scalable three-dimensional (3D) Li-B skeleton structure designed to suppress dendrite formation. The alloy anode demonstrates a lower Young’s modulus, which helps alleviate the accumulation of localized stresses at the interface. Additionally, the 3D alloy anode provided a uniform potential distribution, which promoted homogeneous lithium deposition. Benefiting from these structural advantages, symmetric cells with the Li-B alloy achieved a high critical current density of 2.8 mA cm−2. Notably, Li-B||LPSCl||LVO-NCM ASSLBs exhibited long-term cycling stability, retaining 97.8 % of their capacity after 1500 cycles at 2 C. Furthermore, ASSLBs incorporating the Li-B alloy showed cycling stability comparable with Li-In-based cells, while delivering a higher energy density. Overall, this work presents a practical strategy that may accelerate the commercialization of sulfide-based ASSLBs.