Topic: High power batteries and supercapacitors: challenges or opportunities

Lecturer: Prof. Olivier Crosnier, Nantes Université

Time: October 17th, 10:00, UTC+8

Venue: Meeting Room, Nano Key Lab, State Key Laboratory of Advanced Technology for Materials Synthesis and Processing

Biography: Dr. Olivier Crosnier is an assistant professor at Nantes University (France) since 2007. He is a researcher at Institut des Matériaux de Nantes Jean Rouxel (IMN) and a member of the Frence network of Energy Storage (https://www.energie-rs2e.com/en). His research focuses on new materials for electrochemical energy storage such as electrochemical capacitors and high power devices. He has worked on electrode materials (both positive and negative) for aqueous supercapacitors as well as lithium and sodium-ion batteries, from synthesis to full characterization with specific attention to in situand operando techniques (XRD, Mössbauer, XAS, …). He completed his PhD in 2001 and worked as a postdoctoral fellow at the University of Waterloo (Canada) and ICMCB (Bordeaux, France). He is involved in many French and European programs on energy storage devices. He has co-authored more than 40 papers in the last ten years.

Abstract: Electrochemical capacitors, so-called supercapacitors, are charge storage devices that can complement batteries in many applications requiring high power density, long cycle life, and moderate energy density. Apart from carbon-based electrodes currently implemented in commercial devices, many materials have been envisioned as potential electrodes for supercapacitors, ranging from simple or multi-cationic oxides to metal nitrides or sulfides. Unfortunately, only a few compounds exhibit a true pseudocapacitive behavior (“looks like” capacitive). This electrochemical peculiarity seems related to the intrinsic structural/chemical properties of the material, meaning that regardless of particle size, the electrode exhibits the same electrochemical signature. Thus, investigating nano- or micro-sized compounds as electrodes for supercapacitors involves using advanced in-situ or operando techniques that enable highlighting such pseudocapacitive behavior. More recently, battery-type materials such as niobiates have shown remarkable power densities and high capacities, making them strong competitors for supercapacitors when implemented in high-power batteries. Such intriguing behavior is also due to the nanosize of the investigated compounds. Thus, there is a need to clarify the performance of both types of devices and the extent to which their performances overlap. This lecture aims to give clues about these different electrochemical charge storage behaviors and present research directions for achieving the development of high-power devices.

Rewritten by: Mei Mengqi

Edited by: Li Huihui, Li Tiantian

Source: School of Physics Mechanics