Understanding Electrochemical Stability and Lithium Ion‐Dominant Transport in Concentrated Poly(ethylene carbonate) Electrolyte,ChemElectroChem

当前位置： X-MOL 学术 › ChemElectroChem › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Understanding Electrochemical Stability and Lithium Ion‐Dominant Transport in Concentrated Poly(ethylene carbonate) Electrolyte
ChemElectroChem ( IF 3.5 ) Pub Date : 2018-10-30 , DOI: 10.1002/celc.201801105
Kento Kimura ₁ , Yoichi Tominaga ₁

Affiliation

Ion‐conductive solid polymer electrolytes (SPEs) are important materials for implementing safer energy storage. In the present study we show that a concentrated SPE composed of poly(ethylene carbonate) (PEC) and lithium bis(fluorosulfonyl)imide (LiFSI) has high oxidation tolerance and prevents aluminum corrosion. These properties enable cycling of a LiMn₂O₄ cell charged above 4 V. Battery operation above 4 V is difficult for conventional polyether electrolytes because of their poor electrochemical stability. Mechanistic studies imply that an aggregated solvation structure, in which a large portion of the carbonyl groups interact with Li ions, is correlated with the enhanced electrochemical stability. The studies suggest that relatively rigid structure of PEC induces an increase in conductivity with increasing salt concentration. The increase in conductivity enables concentrated electrolyte with reasonable conductivity and high Li transference number. The present study reveals the clear potential of concentrated SPEs based on unexplored polymers having relatively high glass transition temperature for use in high‐voltage Li batteries.

中文翻译：

了解浓缩聚碳酸亚乙酯电解质中的电化学稳定性和锂离子占主导地位的传输

离子导电固体聚合物电解质（SPE）是实现更安全的能量存储的重要材料。在本研究中，我们表明由聚碳酸亚乙酯（PEC）和双（氟磺酰基）酰亚胺锂（LiFSI）组成的浓缩SPE具有较高的抗氧化性，并可以防止铝腐蚀。这些性质使得LiMn ₂ O ₄循环。电池的充电电压高于4V。对于传统的聚醚电解质，由于其较差的电化学稳定性，很难在4 V以上的电压下操作电池。机理研究表明，大部分的羰基与锂离子相互作用的聚集的溶剂化结构与增强的电化学稳定性有关。研究表明，PEC的相对刚性的结构会随着盐浓度的增加而引起电导率的增加。电导率的增加使得浓缩电解质具有合理的电导率和较高的Li转移数。本研究揭示了用于高压锂电池的，具有较高玻璃化转变温度的，基于未经探索的聚合物的浓缩SPE的明显潜力。

更新日期：2018-10-30

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南