Electrochemical characterization of a novel Si-graphite-Li2.6Co0.4N composite as anode material for lithium secondary batteries

被引：39

作者：

Liu, Y ^{[1
]}

Hanai, K ^{[1
]}

Horikawa, K ^{[1
]}

Imanishi, N ^{[1
]}

Hirano, A ^{[1
]}

Takeda, Y ^{[1
]}

机构：

[1] Mie Univ, Dept Chem, Fac Engn, Tsu, Mie 5148507, Japan

来源：

MATERIALS CHEMISTRY AND PHYSICS | 2005年 / 89卷 / 01期

关键词：

silicon; graphite; Li2.6Co0.4N; composite materials; lithium ion batteries;

D O I：

10.1016/j.matchemphys.2004.08.032

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Dispersing ultrafine silicon particles within a ductile graphite matrix by means of high-energy mechanical milling (HEMM) provides an effective way to alleviate the volume effects of silicon upon the repeated electrochemical Li insertion and extraction, resulting in a significantly improved mechanical strength. However, HEMM increases the initial irreversible capacity to unaccepted levels. This deterrent can be overcome by introducing a certain amount of hexagonal Li2.6CO0.4N into above silicon-graphite hosts. The Si-graphite-Li2.6CO0.4N composite synthesized from two HEMM steps demonstrates a large reversible capacity of ca. 1 Ah g(-1) accompanied with a high cycling stability. Research reveals that the elastic graphite-Li2.6CO0.4N matrix with a good electrical/ionic conductivity can permit the silicon in the matrix to operate while maintaining the morphology integrity. More important, fully lithiated Li2.6CO0.4N plays a role in the capacity compensation in the first cycle that leads to a high initial coulombic efficiency. (C) 2004 Elsevier B.V. All rights reserved.

引用

页码：80 / 84

页数：5

共 19 条

[1] Reaction of Li with alloy thin films studied by in situ AFM [J].