High conductivity LiFePO4/C composite thin films with Ti underlayers deposited by radio frequency sputtering

被引：18

作者：

Chiu, K. -F. ^{[1
]}

tang, H. -Y.

Lin, B. -S.

机构：

[1] Feng Chia Univ, Dept Mat Sci & Engn, Taichung 407, Taiwan

[2] Natl Chi Nan Univ, Dept Appl Chem, Nantou 545, Taiwan

来源：

JOURNAL OF THE ELECTROCHEMICAL SOCIETY | 2007年 / 154卷 / 04期

关键词：

D O I：

10.1149/1.2509285

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

LiFePO4/C thin films have been deposited on Ti-coated Si and stainless-steel substrates by radio frequency magnetron sputtering. Negative electric bias (0,-50,-80 V) and postdeposition vacuum annealing (150-650 degrees C) was applied to modify the film properties. Suitable substrate bias resulted in films with finer grains and pure olivine phase. The films deposited with Ti underlayers exhibited enhanced crystallization, grain sizes, and conductivity, as compared with films deposited without Ti underlayers. Composition depth profiles showed interdiffusion at the film/underlayer interfaces after annealing. Charge-discharge and cyclic voltammetry curves revealed the different electrochemical characteristics of the films. The films with Ti underlayers displayed lower initial capacity than those without underlayers due to heavy doping of Ti. However, the cycling stability is greatly improved, which was attributed to the enhanced adhesion property of the Ti underlayers to the substrates and films.

引用

页码：A364 / A368

页数：5

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