Showing papers by "Alain Levasseur published in 2006"
TL;DR: LiPON films were deposited using radiofrequency magnetron sputtering in a pure N2 gas atmosphere and the influence of rf power, N2 pressure, target-substrate distance and target density on thin film composition and ionic conductivity was studied.
151 citations
TL;DR: In this article, the main redox processes occurring during the first discharge-charge cycle were identified and the growth of a surface layer between the cathode and the liquid electrolyte was evidenced upon the discharge as well as its partial dissolution upon the charge.
58 citations
TL;DR: Thin films prepared by radio frequency magnetron sputtering at various substrate temperatures (Ts) show a discharge capacity at the 20th cycle of 1100 (+/-10) mAh/g, which exhibited excellent capacity retention with a small capacity fade.
Abstract: Lithium nickel vanadate thin films were prepared by radio frequency magnetron sputtering at various substrate temperatures (Ts). These thin films have been investigated as anode electrode material in the use of microbatteries. Films were characterized by Rutherford backscattering spectroscopy, nuclear reaction analysis, Auger electron spectroscopy, glancing-incidence X-ray diffraction analysis, Raman spectroscopy, scanning electron microscopy, atomic force microscopy, and high-resolution transmission electron microscopy techniques. The anodic electrochemical performances of the films have been evaluated by cyclic voltammetry at a scan rate of 1 mV/s and by galvanostatic cycling, with lithium metal as the counter and the reference electrode, and cycled in the range of 0.02-3.0 V at a current density of 75 microA/cm2. Thin films prepared at a Ts of 650 degrees C show a discharge capacity at the 20th cycle of 1100 (+/-10) mAh/g, which exhibited excellent capacity retention with a small capacity fade.
36 citations
TL;DR: In this article, the main redox processes and their reversibility occurring during the 1st, 10th, and 30th discharge-charge cycles were discussed in relation with the electrochemical properties.
17 citations
01 May 2006-Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms
TL;DR: In this article, a negative electrode for LiNiVO4 thin film was used as negative electrode in microbatteries applications, and their film composition and thickness were analyzed by Rutherford backscattering spectroscopy (RBS) and nuclear reaction analysis (NRA) technique by using 4He+, 7Li(p α) 4He reaction respectively.
Abstract: rf-Magnetron sputtered LiNiVO4 thin film was used as a negative electrode for lithium microbatteries applications. Their film composition and thickness were analyzed by Rutherford backscattering spectroscopy (RBS) and nuclear reaction analysis (NRA) technique by using 4He+, 7Li(p α) 4He reaction respectively. The structure, surface roughness and homogeneity of these films have been investigated by X-ray diffraction (XRD), atomic force microscopy (AFM) and auger electron spectroscopy (AES) techniques. The amount of lithium inserted into the LiNiVO4 films was analyzed by RBS and NRA studies. The results are comparable to those obtained from the electro-analytical technique (galvanostatic method), indicating that ion beam techniques are complementary tools for the analysis of lithium metal oxide thin films.
12 citations
Patent•
26 Jan 2006TL;DR: In this paper, an amorphous compound of the formula Li x SM w O y N z is described. The material can be used in microbatteries and elctronic systems and can be prepared in the form of a thin film.
Abstract: The disclosure herein relates to a lithium ion conducting electrolyte. This electrolytic material has improved ionic conductivity. The material disclosed herein is an amorphous compound of the formula Li x SM w O y N z wherein x is between approximately 0.5 and 3, y is between 1 and 6, z is between 0.1 and 1, w is less than 0.3 and M is an element selected from B, Ge, Si, P, As, Cl, Br, I, and combinations thereof. The material can be prepared in the form of a thin film. The electrolyte material can be used in microbatteries and elctronic systems.
6 citations