Highly Reversible Electrochemical Insertion of Lithium, Accompanied With a Marked Color Change, Occuring in Microcrystalline Lithium Nickel Oxide Films

G Campet,M Bourrel,D Ferry,J M Chabagno,J Portier,B Morel,L Benotmane

doi:10.1155/1992/59731

Abstract

Thin films of lithium-nickel oxide, whose texture consists of microcrystallites with an average grain size of 50 Å, permit highly reversible electrochemical insertion of lithium ions in Li+conducting electrolytes. Therefore, the corresponding materials would be of great interest for energy storage applications. In addition, the lithium insertion/extraction reactions in the nickel-based layers are accompanied with a marked color change, making these films of interest for the development of electrochromic displays for the control of light transmission in windows (“smart windows”).

Highlights

Thin film-electrochromic (EC) materials (ECM) and displays (ECD) present a basis for light modulators and other electro-optic devices
M1 and M2 should be selected among transition metal oxides, such as: (i) WO3, MOO3, V205, TiO2; they color cathodically and, constitute in thin film the M electrodes of the ECD [1,2,3]
We have recently reported on a new strategy,* and related experiments, that have enabled us of bringing to light a new family of ECM: electrodes operating with Li / ions (designated below as ECM2 (Li/)) [11, 12]

Summary

INTRODUCTION

Thin film-electrochromic (EC) materials (ECM) and displays (ECD) present a basis for light modulators and other electro-optic devices. This paper presents the results of some of our investigations, within the framework of this strategy, on a new ECM2 (Li +) of composition: For sake of clarity we will mainly focus on the EC properties of the films (results concerning the determinations of film structure and texture, chemical and physical analysis, transport properties, etc., will be reported elsewhere [13]). In this prospect, their similar optical properties with "X-ray amorphous" WO3 films [13] will be evaluated. ECD, using WO3 as ECM, and nickel or chromium-based ECM2 will be investigated

EXPERIMENTAL

ELECTROCHROMIC EVALUATION OF THE ECD

CONCLUSION