Simultaneous Improvement of Ionic Conductivity and Mechanical Strength in Block Copolymer Electrolytes with Double Conductive Nanophases
Xiao‐Han Cao, Jun‐Huan Li, Mu‐Jia Yang, Jialiang Yang, Ruiyang Wang, Xinghong Zhang, Junting Xu
Abstract
Abstract The most daunting challenge of solid polymer electrolytes (SPEs) is the development of materials with simultaneously high ionic conductivity and mechanical strength. Herein, SPEs of lithium bis‐(trifluoromethanesulfonyl)imide (LiTFSI)‐doped poly(propylene monothiocarbonate)‐ b ‐poly(ethylene oxide) (PPMTC‐ b ‐PEO) block copolymers (BCPs) with both blocks associating with Li + ions are prepared. It is found that the PPMTC‐ b ‐PEO/LiTFSI electrolytes with double conductive phases exhibit much higher ionic conductivity (2 × 10 −4 S cm −1 at r.t.) than the BCP electrolytes with a single conductive phase. Concurrently, the storage moduli of PPMTC n ‐ b ‐PEO 44 /LiTFSI electrolytes are ≈1–4 orders of magnitude higher than that of the neat PEO/LiTFSI electrolytes. Therefore, simultaneous improvement of ionic conductivity and mechanical properties is achieved by construction of a microphase‐separated and disordered structure with double conductive phases.