Boosting the Performance of Sb₂Se₃ Cathode‐Based All‐Solid‐State Batteries by Carbon Coating

AbstractAll‐solid‐state battery (ASSB) is a potential future energy storage technology to power the future world. However, the solid–solid contacts among the various components in ASSB often require a high stack pressure which is unrealistic in practical applications. Here it is shown that by carbon‐coating Sb2Se3 (Sb2Se3@C) nanorods, a record low stack pressure is attained, and the Sb2Se3@C electrode exhibits outstanding performance of 862 mAh g−1 over 50 cycles at 0.1 A g−1 when it is operated at 5 MPa stack pressure in an ASSB using LiIn anode and Li10Si0.3PS6.7Cl1.8 solid‐state electrolytes. Furthermore, a record high active material loading (the mass fraction of Sb2Se3@C being 0.7 in composite cathode) is achieved, and the Sb2Se3@C based ASSB delivers a reversible capacity of 2.6 mAh cm−2 at 0.1 A g−1 after 100 cycles. This work provides a strategy to significantly increase the cathode active material loading and dramatically reduce the stack pressure of ASSBs, which brings it one step closer toward the practical implementation of ASSBs for energy storage applications.