Comprehensive Understanding of Sodium‐Ion Capacitors: Definition, Mechanisms, Configurations, Materials, Key Technologies, and Future Developments. Issue 16 (10th March 2021)

• Record Type: Journal Article
• Authors: Cai, Peng; Zou, Kangyu; Deng, Xinglan; Wang, Baowei; Zheng, Min; Li, Longhao; Hou, Hongshuai; Zou, Guoqiang; Ji, Xiaobo
• Is Part Of: Advanced energy materials. Volume 11:Issue 16(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-03-10
• Subjects: electrochemistry -- flexible capacitors -- presodiation -- pseudocapacitance -- sodium‐ion hybrid capacitors; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202003804
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: In the past 10 years, preeminent achievements and outstanding progress have been achieved on sodium‐ion capacitors (SICs). Early work on SICs focussed more on the electrochemical performance. While it is easy to confirm which specific electrodes exhibit excellent properties, it is difficult to understand the mechanisms which are most promising for the next generation of SICs. From the early research in supercapacitors iterations to the present well‐developed Na‐ion batteries, the evolution of the controversial pseudocapacitive mechanism for SICs has been full of breakthroughs and back tracing steps. Moreover, as the research has progressed and the interests have changed, different emphases on the different subdisciplines (cell configurations, flexible devices, and presodiation technologies) have increased. In this review, first, the electric double layer mechanism, battery‐type mechanism, and the controversial pseudocapacitance mechanism are systematically analyzed and compared. Subsequently, mechanism‐oriented SICs cell configurations with different cathode and anode mechanisms are discussed. Moreover, the characteristics and features of electrode materials in different SICs cell configurations are summarized. Finally, key technologies and possible future developments are discussed. This review summarizes SICs from a broad and macro perspective from mechanisms to cell configurations, from cathodes to anodes, and from history to future, and offers a deep understanding of SICs devices. Abstract : This review summarizes sodium‐ion capacitors (SICs) from a broad perspective, from mechanism to cell configuration, from cathode to anode, and from history to future, and offers a deep understanding of SICs devices. Initially, pseudocapacitive mechanisms are systematically compared. Subsequently, mechanism‐oriented SICs are discussed. Moreover, characteristics of electrode materials are summarized. Finally, the key technologies are described.