Ice-Templated Synthesis of Mixed Ion-Electron Conductors for Functional Interlayers in Lithium Batteries

Despite ongoing efforts to develop sustainable lithium batteries with eco-friendly cathode materials, such as organic or sulfur-based compounds, challenges such as poor charge transport and severe redox shuttling persist. Interface engineering at the electrode-electrolyte interface remains crucial for improving the performance of these batteries. Herein, an ice-templated synthesis of mixed ion-electron-conducting interlayers design is presented to enhance redox kinetics and cycling stability in lithium batteries. The interlayers consist of hierarchically porous conducting polymer nanosheets with Li⁺-conducting polymeric nanoparticles anchored to the pore walls. This architecture simultaneously enhances electrical conductivity (6.0 S cm^{- 1}) and ionic conductivity (0.22 mS cm^{- 1}), and effectively mitigates shuttle effects by confining soluble redox-active species within the porous interlayer. When applied to lithium-organic batteries with C₆O₆ cathodes, the batteries achieve a high specific capacity of 557 mAh g^{- 1} at 48 mA g^{- 1}. In lithium-sulfur cells with elemental sulfur cathodes, the cells deliver 912 mAh g^{- 1} at 167 mA g^{- 1}, 789 mAh g^{- 1} at 0.84 A g^{- 1}, 717 mAh g^{- 1} at 1.7 A g^{- 1}, and 544 mAh g^{- 1} at 3.3 A g^-1 with cycling stability over 120 cycles. This study establishes a scalable and adaptable platform for the advancement of sustainable lithium battery technologies.