Mechanically Interlocked Polymer Electrolyte with Built-In Fast Molecular Shuttles for All-Solid-State Lithium Batteries

Abstract

The mobility of molecular shuttles inside a mechanically interlocked polymer (MIP) can improve the ionic conductivity and electron transport capacity of a solid polymer electrolyte (SPE) and maintain a mechanically tough structure. The polyrotaxane-based MIP electrolyte with a necklace-like molecular structure exhibits high ionic conductivity (sigma = 5.93 x 10(-3) S cm(-1) at 25 degrees C and 1.44 x 10(-2) S cm(-1) at 60 degrees C), a high Li+ ion transference number (t(+) = 0.71), and high electrochemical oxidation stability (approximate to 4.7 V vs Li+/Li). When SPEs are used in Li-based batteries, a high Coulombic efficiency (>= 98.5%), an excellent rate capability, and fast charging (>= 2C) can be achieved using a "built-in molecular shuttle" design.