Synergistic Electrochemical and Mechanical Enhancement in Structural Batteries based on a Porous Resin

Structural batteries (SBs) show promising potential for mobile intelligent equipment, as they can simultaneously bear mechanical loads and store energy, but are limited by high interfacial impedance, low ionic conductivity, and poor cycling stability. Herein, we develop a rigid structural battery electrolyte (SBE) with high ion-transport efficiency, in which a porous resin skeleton absorbs liquid electrolyte, to fabricate SBs via vacuum-assisted resin transfer molding. This design enables the uniform distribution of interconnected porous resin channels throughout the electrodes and separator, facilitating efficient lithium-ion transport while maintaining high structural rigidity and a stable solid electrolyte interphase (SEI), as verified by microscopic and electrochemical analyses. Consequently, the fabricated SB achieves an outstanding energy density of 46.6 Wh kg⁻¹ at 0.1 C and retains 86% capacity after 100 cycles at 0.2 C, while exhibiting a tensile strength and modulus of 214 MPa and 24 GPa, respectively. Notably, by optimizing the electrode mass loading and carbon fiber current collector, the mechanical properties can be further enhanced to 270 and 357 MPa. This work provides a promising strategy to simultaneously enhance the electrochemical-mechanical properties of SBs while showing the practical scalability and design flexibility.