Electrochemical capacitors can store electrical energy harvested from intermittent sources and deliver energy quickly, but their energy density must be increased if they are to efficiently power flexible and wearable electronics, as well as larger equipment. This Review summarizes progress in the field of materials for electrochemical capacitors over the past decade as well as outlines key perspectives for future research. We describe electrical double-layer capacitors based on high-surface-area carbons, pseudocapacitive materials such as oxides and the two-dimensional inorganic compounds known as MXenes, and emerging microdevices for the Internet of Things. We show that new nanostructured electrode materials and matching electrolytes are required to maximize the amount of energy and speed of delivery, and different manufacturing methods will be needed to meet the requirements of the future generation of electronic devices. Scientifically justified metrics for testing, comparison and optimization of various kinds of electrochemical capacitors are provided and explained.

电化学电容器可以存储从间歇性来源收集的电能并快速传递能量，但是如果要有效地为柔性和可穿戴电子设备以及大型设备供电，则必须增加其能量密度。这篇综述总结了过去十年中电化学电容器材料领域的进展，并概述了未来研究的关键观点。我们将介绍基于高表面积碳，双层伪电容材料（例如氧化物和称为MXene的二维无机化合物）以及新兴的物联网微型设备的双电层电容器。我们表明，需要新的纳米结构电极材料和匹配的电解质来最大化能量和输送速度，并且需要不同的制造方法来满足下一代电子设备的要求。提供并解释了用于测试，比较和优化各种电化学电容器的科学合理的度量标准。