Realizing high-voltage and ultralong-life supercapacitors by a universal interfacial engineering strategy

JOURNAL OF POWER SOURCES

卷:510

Article

Bai, Yuge¹  Li, Nan¹  Yang, Chao¹  Wu, Xiaodong¹  Yang, Hengrui¹  Chen, Weimeng¹  Li, Hongjie¹  Zhao, Bin¹  Wang, Peng-Fei¹  Han, Xiaogang^1,2 

[1] Xi An Jiao Tong Univ, Sch Elect Engn, State Key Lab Elect Insulat & Power Equipment, Xian 710049, Shaanxi, Peoples R China

[2] Key Lab Smart Grid Shaanxi Prov, Xian 710049, Shaanxi, Peoples R China

关键词: Atomic layer deposition;    Dielectric constant;    Surface charge density;    Operational voltage window;    Flexible device;    Energy density;   

DOI  :  10.1016/j.jpowsour.2021.230406

来源: Elsevier

【 摘 要 】

Low energy density hinders the development of supercapacitors in the market of large hybrid power equipment and electric vehicles that demand much higher energy density. Herein, we conduct a facile and environmentally friendly method to modify the electrodes of supercapacitors through coating a dielectric thin film by atomic layer deposition (ALD) technique, which profoundly improves the electrochemical performance of the electrodes. In specific, the gravimetric capacitance of the ALD-Ti modified electrodes is characterized by 35% significant promotion comparing to the commercialized pristine counterparts, and the operational voltage window of the ALD treated electrodes can expand to 3.5 V using organic electrolyte with remarkable capacitance retention (over 83%) even after 20000 cycles. Besides, appropriate models are established to discuss the detailed charge storage mechanism and possible reasons for good stability of modified electrodes under higher operational voltage. Moreover, the excellent rate and cycling performance of ALD modified electrodes in flexible electrochemical double-layer capacitor (EDLCs) at the bending state substantiates the application superiority of ALD modified electrodes in flexible devices. The unusual combination of charge storage mechanisms of dielectric capacitors and EDLCs established in our work represents specific properties in great need for energy storage applications.

【 授权许可】

Free