Rational design of stable 4 V lithium ion capacitor. (September 2016)

• Record Type: Journal Article
• Authors: Lee, Wee Siang Vincent; Peng, Erwin; Li, Meng; Huang, Xiaolei; Xue, Jun Min
• Is Part Of: Nano energy. Volume 27(2016:Sep.)
• Page Start: 202
• Page End: 212
• Publication Date: 2016-09
• Subjects: Amorphous carbon -- Wide cell potential window -- Lithium ion capacitor -- Electrolyte decomposition; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2016.07.018
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Li ion capacitor (LIC) has emerged as an exciting approach to synergistically combine low potential Li ion battery electrode with high potential supercapacitor electrode. Although wide cell potential window can be achieved through such coupling, current LICs continue to operate at a deliberately constricted cell potential window (2–3 V) due to electrolyte degradation concerns caused by the presence of graphitic structure. Herein, highly stable 4 V LIC with high energy and power density was rationally designed with 3D amorphous carbon positive electrode which demonstrated exceptional tolerance to high voltage as compared to graphitic carbon. The as-assembled 4 V LIC, coupled with high capacity MnFe2 O4 /carbon negative electrode, exhibited remarkable capacity retention of 86.5% after cycling for 6000 cycles at 2 A g −1, with ca. 100% coulombic efficiency (indicating minimal electrolyte decomposition), while achieving high energy density of 157 W h kg −1 at power density of 200 W kg −1 . This work demonstrates the advantages of employing amorphous carbon as compared to more graphitic carbon as positive electrode and thus, serves as a guideline for designing stable 4 V LIC with amorphous carbon. Graphical abstract: This work demonstrates the importance of employing amorphous carbon as positive electrode in LIC. The couplings with more graphitic carbon led to poor electrolyte stability at wide voltage due to presence of graphitic strucutre. Thus this work shows that positive electrode architecture ( i.e. amorphous degree) can affect the system stability. Highlights: Importance of employing amorphous carbon as positive electrode in LIC. Couplings with more graphitic carbon led to poor electrolyte stability at wide voltage due to presence of graphitic strucutre. Positive electrode architecture ( i.e. amorphous degree) can affect the system stability. Assembled cell is able to operate at potential window of 4 V with 86.5% capacitance retention over 6000 cycles at 2 A g −1