A High‐Performance Silicon‐Based Anode Enabled by Hybrid Pathways for All‐Solid‐State Batteries

Abstract All‐solid‐state batteries (ASSBs) with lithium metal anodes offer high energy density while face commercialization challenges due to severe interfacial reactions and lithium dendrite formation. Silicon, with its high abundance and specific capacity, is a promising alternative anode material for ASSBs. However, its low ionic and electronic conductivity, along with volumetric expansion‐induced cracking, limits its rate capability and cycling stability in ASSBs. Here, this study designs a metallic network composed of lithium‐indium alloys interspersed among silicon particles, serving as an ionic‐electronic hybrid conductor. This network not only enhances conductivity but also mitigates stress concentration, improving mechanical stability and cycling performance of silicon anode. As a result, ASSBs of In‐Si||Li 5.5 PS 4.5 Cl 1.5 || LiNi 0.9 Co 0.05 Mn 0.05 O 2 exhibit exceptional rate capability, achieving 80% capacity when comparing charging rate between 6C and 1C. Furthermore, under a current density of 3.69 mA cm −2 , 98.5% capacity retention over 2000 cycles is achieved. These results highlight the practical potential of the silicon composite anode for high‐performance ASSBs.