当前位置: X-MOL 学术Nat. Mater. › 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.)
Molecular crowding electrolytes for high-voltage aqueous batteries.
Nature Materials ( IF 37.2 ) Pub Date : 2020-04-20 , DOI: 10.1038/s41563-020-0667-y
Jing Xie 1 , Zhuojian Liang 1 , Yi-Chun Lu 1
Affiliation  

Developing low-cost and eco-friendly aqueous electrolytes with a wide voltage window is critical to achieve safe, high-energy and sustainable Li-ion batteries. Emerging approaches using highly concentrated salts (21-55 m (mol kg-1)) create artificial solid-electrode interfaces and improve water stability; however, these approaches raise concerns about cost and toxicity. Molecular crowding is a common phenomenon in living cells where water activity is substantially suppressed by molecular crowding agents through altering the hydrogen-bonding structure. Here we demonstrate a 'molecular crowding' electrolyte using the water-miscible polymer poly(ethylene glycol) as the crowding agent to decrease water activity, thereby achieving a wide electrolyte operation window (3.2 V) with low salt concentration (2 m). Aqueous Li4Ti5O12/LiMn2O4 full cells with stable specific energies between 75 and 110 W h kg-1 were demonstrated over 300 cycles. Online electrochemical mass spectroscopy revealed that common side reactions in aqueous Li-ion batteries (hydrogen/oxygen evolution reactions) are virtually eliminated. This work provides a path for designing high-voltage aqueous electrolytes for low-cost and sustainable energy storage.

中文翻译:

高压水性电池的分子拥挤电解质。

开发具有宽电压范围的低成本,环保型水性电解质对于实现安全,高能和可持续的锂离子电池至关重要。使用高浓度盐(21-55 m(mol kg-1))的新兴方法产生了人造固体-电极界面并改善了水稳定性;然而,这些方法引起对成本和毒性的关注。分子拥挤是在活细胞中的常见现象,在活细胞中,通过改变氢键结构,分子拥挤剂基本上抑制了水的活性。在这里,我们展示了一种“分子拥挤”电解质,该电解质使用与水混溶的聚合物聚乙二醇作为拥挤剂来降低水活度,从而以较低的盐浓度(2 m)实现了较宽的电解质工作范围(3.2 V)。在300次循环中,证实了Li4Ti5O12 / LiMn2O4水溶液具有在75和110 W h kg-1之间的稳定的比能。在线电化学质谱表明,锂离子电池水溶液中常见的副反应(氢/氧放出反应)已基本消除。这项工作为设计用于低成本和可持续能源存储的高压水性电解质提供了一条途径。
更新日期:2020-04-24
down
wechat
bug