Electrode Engineering Strategy for 400 Wh kg ⁻¹ All‐Solid‐State Pouch Cells: Spatial Optimization of Charge Carriers Based on Electron and Ion Transport Flux

Abstract Efficient ion and electron transport is essential for achieving high performance all‐solid‐state batteries (ASSBs). However, the proportion of ionic and electronic conductors also significantly influences the energy density of ASSBs. In this study, a rational spatial distribution of charge carriers based on ion and electron transport flux is proposed to construct an efficient dual‐conducting network, thereby maximizing the utilization of both the solid electrolyte (SE) and conductive agent. Specifically, the required content of SE in the cathode increases progressively from the current collector toward the electrolyte layer, while the distribution of conductive agent exhibits the opposite trend. Electrode structure simulations and electrochemical performance evaluations further confirm the effectiveness of this design. By implementing this approach, a high active material fraction of 91.5% is achieved in the cathode, corresponding to an areal capacity of 4 mAh cm −2 . Furthermore, this optimized electrode architecture is successfully fabricated through a dry electrode process and integrated into pouch cells. The as‐made 5 Ah pouch cells deliveres a high energy density exceeding 400 Wh kg − 1 . This work presents a practical strategy for developing ASSBs with high energy density.