Extremely pseudocapacitive interface engineered CoO@3D-NRGO hybrid anodes for high energy/ power density and ultralong life lithium-ion batteries

Although secondary Li-ion batteries are widely used for electrochemical energy storage , low energy (100–300 Wh kg −1 ) and power density (250–400 W kg −1 ) are limiting their applications in several areas including long-range electric vehicles. Herein, we demonstrate high energy (400 Wh kg −1 ) and power density (1 kW kg −1 ) Li-ion batteries (considering the weight of both electrodes) based on extremely pseudocapacitive interface engineered CoO@3D-NRGO hybrid anodes. These values are 2.8 and 2.3-fold higher respectively compared to graphite‖LiNiMnCoO 2 full-cells under similar experimental conditions. Three-dimensional anode architecture presented here composed of ultrafine CoO nanoparticles (∼10 nm) chemically bonded to nitrogen-doped reduced graphene-oxide. This hybrid anode demonstrated excellent pseudocapacitance (∼92%), specific capacity (1429 mAh g −1 @ 25 mA g −1 ), rate performance (906 mAh g −1 @ 5 A g −1 ), and cycling stability (990 mAh g −1 after 7500 cycles @ 5 A g −1 ). Outstanding electrochemical performance of CoO@3D-NRGO‖LiNiMnCoO 2 full-cells is credited to the extreme pseudocapacitance of CoO@3D-NRGO anode resulting from Li 2 O/Co/NRGO nanointerfaces and Co–O–C bonds. The demonstrated strategy of interfacial engineering can also be extended for other environmental friendly/inexpensive transition metal oxide (Fe 2 O 3 , MnO 2 etc.) anodes for high energy/power density and ultra-long-life Li-ion batteries.