Lithium-Ion Capacitor Based on Electrodes Constructed Via Electrostatic Spray Deposition

Abstract

Conventional Electrochemical double-layer capacitors (EDLCs) are well suited as power devices that can provide large bursts of energy in short time periods. However, their relatively poor energy densities hinder their application in devices that require a simultaneous supply of both high energy and high power. In the wake of addressing this shortcoming of EDLCs, the concept of hybridization of lithium-ion batteries (LIBs) and EDLCs has gained significant scientific interest in past few years. Such a device, generally referred to as the “lithium-ion capacitor” typically utilizes a lithium intercalating electrode along with a fast charging capacitor electrode in a lithium-containing electrolyte. Herein we have constructed a lithium ion capacitor comprising a Li4Ti5O12 –TiO2 (LTO-TiO2) anode and a graphene and carbon nanotube (G-CNT) composite cathode using electrostatic spray deposition (ESD). The morphology and material properties were studied using scanning and transmission electron microscopy and X-ray diffraction studies, respectively. Electrochemical characterization was thereafter carried out for both the half cells as well as full cells.