Pressure-Resilient Electron-Ion Networks via Multifunctional Carbon Conductive Agents for High-Rate Solid-State...

Silicon-based all-solid-state batteries (ASSBs) promise high safety and energy density, yet their rate capability remains fundamentally constrained by the disruption of continuous electron-ion transport networks induced by large volume variations. Herein, we introduce a pressure-resilient electron-ion network enabled by a molten-salt-mediated multifunctional carbon conductive agent featuring a graphene-like stacked framework with uniformly distributed nanopores. This architecture enables synergistic electron-ion transport (with electronic and ionic conductivities of 133.26 S cm^-1 and 1.89 mS cm^-1), accommodates large deformation (up to 91.3% strain) without structural failure and retains high elasticity under a compressive strain of 80.6%. Operando expansion and kinetic analysis reveal that the elastic network dynamically adapts to silicon volume changes, preserving interfacial integrity and continuous transport pathways. As a result, the composite silicon anode delivers high capacity of 1672.2 mA h g^-1 at 3C with 76.5% retention over 300 cycles, and notably sustains 1030.0 mA h g^-1 at 3C even under 20 MPa. In full cells, it achieves 76.8 mA h g^-1 at 3C under 20 MPa, 2.7 times higher than those based on pristine silicon anodes. Beyond silicon, this strategy can extend to other alloy-type anodes (e.g., Sn), offering a general paradigm for constructing pressure-resilient electron-ion networks toward high-rate ASSBs.