Elastomeric Electrolytes via Thiourethane Dynamic Chemistry and Hierarchical Hydrogen-Bonding Interactions

Elastomeric electrolytes have the potential to enhance the safety of lithium-based batteries and align with the trend toward flexible wearable devices. However, constructing elastomeric electrolytes with excellent mechanical and electrochemical properties remains an extremely challenging task due to the antithetical requirements of polymer chain kinematics. Herein, a series of novel three-dimensional cross-linked polyurea (PDEU)-based gel elastomeric electrolytes (GPDEUs) are developed through incorporating a dynamic thiourethane bond via a self-catalyzed strategy and hierarchical hydrogen-bonding interactions. The segments of the polar poly(propylene glycol) poly(ethylene glycol) block polymer (PPEG) serve as a polymeric solvent to strongly interact with liquid electrolytes via hydrogen bonds, coordination bonds, and van der Waals forces. Due to polarity incompatibility, the segments of nonpolar poly(dimethylsiloxane) (PDMS) can isolate hydrogen bonds between ureido from polar liquid electrolytes and maintain structural stability. The introduction of robust and flexible PDMS segments greatly broadens the scope of liquid electrolytes suitable for PDEUs, and the corresponding GPDEUs could maintain adequate mechanical properties. Further, in combination with the dynamic chemical cross-linking structure, the PDMS domains endow GPDEUs with excellent elasticity, enabling them to accommodate the volume change of the lithium metal anode during dissolution and deposition processes while inhibiting the growth of lithium dendrites. The symmetric Li|GPDEUs|Li cell can be continuously operated for more than 1600 h at 0.1 mA cm–2. Moreover, the stretchable full battery assembled with GPDEUs can function normally, even under bending, stretching, and puncture conditions.