Carbon surface layers on a high-rate LiFePO4

被引:83
作者
Gabrisch, Heike [1 ]
Wilcox, James D.
Doeff, Marca M.
机构
[1] Univ New Orleans, Coll Sci, Adv Mat Res Inst, New Orleans, LA 70148 USA
[2] Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA
关键词
D O I
10.1149/1.2203309
中图分类号
O646 [电化学、电解、磁化学];
学科分类号
081704 ;
摘要
Transmission electron microscopy (TEM) was used to image particles of a high-rate LiFePO4 sample containing a small amount of in situ carbon. The particle morphology is highly irregular, with a wide size distribution. Nevertheless, coatings, varying from about 5 to 10 nm in thickness, could readily be detected on surfaces of particles as well as on edges of agglomerates. Elemental mapping using energy-filtered TEM indicates that these very thin surface layers are composed of carbon. These observations have important implications for the design of high-rate LiFePO4 materials in which, ideally, a minimal amount of carbon coating is used. (c) 2006 The Electrochemical Society.
引用
收藏
页码:A360 / A363
页数:4
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