Electrodeposited Si-O-C as a High-Rate Performance Anode for Li-ion Capacitor

Li-ion capacitors (LIC) which bridge the advantages of supercapacitors and Li-ion batteries have attracted a great deal of attention as a promising energy storage device. In this study, we synthesize the Si-O-C by electrodeposition at low levels of electricity below 2.0 C cm(-2) as an anode for LIC. The deposited Si amounts are controlled by charge density during electrodeposition from 0.3 to 1.0 C cm(-2). The material and electrochemical characteristics of Si-O-C fabricated at a charge density of 1.0 C cm(-2) are studied. The LIC consisting of Si-O-C anode shows an encouraging 95% retention of the initial capacity after 1000 cycles. In addition, the LIC shows a capacity retention ratio of 94% at 140 C-rate. This study reveals the potential prospect to use Si-O-C fabricated by electrodeposition as an anode for a high-rate capability for LIC. (C) The Author(s) 2019. Published by ECS.