T-Nb2O5 embedded carbon nanosheets with superior reversibility and rate capability as an anode for high energy Li-ion capacitors. Issue 4 (18th March 2019)

• Record Type: Journal Article
• Authors: Li, Dong; Shi, Jing; Liu, Haolin; Liu, Chunyue; Dong, Guanghe; Zhang, Hao; Yang, Yunpeng; Lu, Gaofei; Wang, Huanlei
• Is Part Of: Sustainable energy & fuels. Volume 3:Issue 4(2019)
• Page Start: 1055
• Page End: 1065
• Publication Date: 2019-03-18
• Subjects: Renewable energy sources -- Periodicals; Fuel cells -- Periodicals; Electric batteries -- Periodicals; Electrochemistry -- Periodicals; 660.297
• DOI: 10.1039/c9se00052f
• Languages: English
• ISSNs: 2398-4902

Abstract

Abstract : A lithium-ion capacitor was fabricated by using T-Nb2 O5 /GCN anode and GCN cathode, which exhibits excellent energy/power density in 0–3.5 V and bridges the gap between batteries and supercapacitors. Abstract : Li-ion capacitors (LICs), structured with an energy-type lithium-ion battery (LIB) anode and a power-type electrochemical capacitor (EC) cathode, have attracted great attention owing to the combined advantages of high energy density of LIBs and high power density of ECs. Unfortunately, the imbalance in reaction kinetics between the sluggish faradaic lithium-intercalation anode and rapid non-faradaic capacitive cathode is the main impediment in developing high-performance LICs. Herein, a new type of LIC with an orthorhombic T-Nb2 O5 /graphene-like carbon nanosheet (T-Nb2 O5 /GCN) anode and graphene-like carbon nanosheet (GCN) cathode is designed and fabricated. Benefiting from the merits of the structure and pseudocapacitive properties of the T-Nb2 O5 /GCN nanocomposite, a high capacity of ∼170 mA h g −1 at 0.1 A g −1 (1.0–3.0 V vs. Li/Li + ) and a superior capacity retention of 90% after 500 cycles are obtained in a half-cell. In the voltage range of 0–3.5 V, the LIC exhibits a superior energy density of 129 W h kg −1 and power density of 32 kW kg −1 . In addition, the capacity retention of the LIC is 80% after 10 000 cycles. This design provides an effective way to fabricate high-performance LICs.