Catalyst-Free Dynamic\nNetworks for Recyclable, Self-Healing\nSolid Polymer Electrolytes

Abstract

Polymer networks with dynamic covalent cross-links act\nas solids\nbut can flow at high temperatures. They have been widely explored\nas reprocessable and self-healing materials, but their use as solid\nelectrolytes is limited. Here we report poly­(ethylene oxide)-based\nnetworks with varying amounts of lithium bis­(trifluoromethanesulfonyl)­imide\n(LiTFSI) to understand the impact of a salt on the ion transport and\nnetwork dynamics. We observed that the conductivity of our dynamic\nnetworks reached a maximum of 3.5 × 10^–4 S/cm\nat an optimal LiTFSI concentration. Rheological measurements showed\nthat the amount of LiTFSI significantly affects the mechanical properties,\nas the shear modulus varies between 1 and 10 MPa and the stress relaxation\nby 2 orders of magnitude. Additionally, we found that these networks\ncan efficiently dissolve back to pure monomers and heal to recover\ntheir conductivity after damage, showing the potential of dynamic\nnetworks as sustainable solid electrolytes.