Trapping Anions to Govern the Li<sup>+</sup> Local Coordination Environment for a Highly Li<sup>+</sup> Conductive Solid Polymer Electrolyte
Yichen Xue, Haitao Zhao, Xiaoyu Zhou, Huandi Zhang, Zehua Zhao, Xiaowei Shi, Junpeng Liu, Jiamei Liu, Lei Li
Abstract
High Resolution Image Download MS PowerPoint Slide Solid polymer electrolytes (SPEs) confront the major challenge of low ionic conductivity. The Li + local coordination environment in SPEs affects the ionic conductivity. Herein, a highly ionic conductive SPE is designed and experimentally realized via governing the Li + local coordination environment through 4-acetylphenylboronic acid (APBA). The –OH functional groups in APBA react with F atoms in the PVDF-HFP polymer chain segment and O atoms in TFSI – to form the OH···F hydrogen bond and the OH···O hydrogen bond. This weakens the Li + local coordination with PVDF-HFP and TFSI –, facilitating more free-Li + release and strengthening the molecular dynamics of Li + . This variation results in the greatly increased Li + ionic conductivity from 0.63 × 10 –4 to 2.39 × 10 –4 S/cm of SPE with APBA at 25 °C. This electrolyte makes the symmetric cells full cells with promising electrochemical performance. The strategy provided here is helpful for the development of highly ionic conductive SPEs.