A Versatile Capacity Balancer for Asymmetric Supercapacitors,Advanced Energy Materials

当前位置： X-MOL 学术 › Adv. Energy 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.)

A Versatile Capacity Balancer for Asymmetric Supercapacitors
Advanced Energy Materials ( IF 24.4 ) Pub Date : 2020-08-06 , DOI: 10.1002/aenm.202001608
Lintong Hu ₁ , Lanlan Xue ₁ , Jinzhou Fu ₁ , Ping Xiao ₁ , Tianyou Zhai ₁ , Huiqiao Li ₁

Affiliation

Asymmetric supercapacitors (ASCs) with high theoretical energy density have attracted extensive attention during the past years. However, the huge capacity gap between the two electrodes greatly limits high energy density. Regulating electrode mass can make the capacity balanced, while sacrificing weight and volume. Herein, a soluble bipolar molecule, 4‐hydroxy‐2,2,6,6‐tetramethylpiperidinyloxyl (4‐OH‐TEMPO), is proposed as a versatile mediator in the electrolyte to balance the capacity gap in different types of ASCs. 4‐OH‐TEMPO is able to quickly obtain or lose electrons at different potentials regardless of the pH values, thus can contribute large redox capacity at the interface of capacitive electrode in ASCs in both positive or negative electrodes, acidic or alkaline systems. A case study of two typical ACSs is presented, Zn//activated carbon (AC) system with 4‐OH‐TEMPO for positive electrode enhancement in a mildly acidic electrolyte and AC//Ni(OH)₂ system with 4‐OH‐TEMPO for negative electrode enhancement in an alkaline electrolyte. Both demonstrate that the addition of 4‐OH‐TEMPO can effectively balance the capacity mismatching between two electrodes, and its capacity contribution can be adjusted by concentration. The energy density of the two ACSs with 4‐OH‐TEMPO can be greatly promoted without significant sacrifice of the device's volume or mass.

中文翻译：

用于不对称超级电容器的多功能容量平衡器

在过去的几年中，具有高理论能量密度的不对称超级电容器（ASC）引起了广泛的关注。然而，两个电极之间的巨大电容间隙极大地限制了高能量密度。调节电极质量可以使容量平衡，同时又可以减轻重量和体积。本文提出了一种可溶性双极性分子4-羟基-2,2,6,6-四甲基哌啶基氧基（4-OH-TEMPO）作为电解质中的通用介体，以平衡不同类型的ASC中的容量差距。无论pH值如何，4-OH-TEMPO都能迅速获得或失去处于不同电势的电子，因此可以在酸性或碱性体系的ASC中，在ASC中的电容电极界面上贡献较大的氧化还原容量。提出了两个典型ACS的案例研究，具有4-OH-TEMPO的_2号系统，用于增强碱性电解质中的负电极。两者都表明添加4-OH-TEMPO可以有效平衡两个电极之间的容量失配，并且其容量贡献可以通过浓度进行调整。可以大大提高两个带有4-OH-TEMPO的ACS的能量密度，而不会显着降低设备的体积或质量。

更新日期：2020-09-22

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11