Structural changes of bare and AIPO4-coated LixCoO2 (x = 0.24 and 0.1) upon thermal annealing ≥200°C

被引：4

作者：

Kim, Yoojung ^{[1
]}

Hong, Youngsik ^{[2
]}

Ryu, Kwang Sun ^{[3
]}

Kim, Min Gyu ^{[4
]}

Cho, Jaephil ^{[1
]}

机构：

[1] Hanyang Univ, Dept Appl Chem, Ansan, South Korea

[2] Seoul Natl Univ Educ, Dept Sci Educ, Seoul, South Korea

[3] Univ Ulsan, Dept Chem, Ulsan 680749, South Korea

[4] Pohang Accelerator Lab, Beamline Res Div, Pohang, South Korea

来源：

JOURNAL OF POWER SOURCES | 2008年 / 179卷 / 02期

关键词：

structural change; AIPO(4) coating; LixCoO2; thermal annealing; spinel phase; lithium-ion cell;

D O I：

10.1016/j.jpowsour.2008.01.054

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Structural changes of bare and AIPO(4)-coated LiCoO2 with a coating thickness of 20 and 200 nm are investigated at x = 0.24 and 0. 1 after thermal annealing at 200, 300, and 400 degrees C using XRD and Co K-edge XANES (X-ray absorption near-edge structure) and EXAFS (extended X-ray absorption fine structure). Both the bare and coated cathodes exhibit faster phase transformation into spinel phases at lower annealing temperatures as x in LixCoO2 is decreased. Bare LixCoO2 cathodes exhibit phase transitions from LixCo2O4 to Co3O4 spinel as the annealing temperature is increased and the x is value decreased, which suggests a possible reaction according to (1/2)LixCo2O4 -> xLi(2)CO(3) + (1/3)Co3O4 + (2/3)O-2. However, the coated cathodes sustain a Li(x)Co(2)O(4)phase even at 400 degrees C and x=0.1. This indicates that the AIPO(4) coating layer suppresses the Li,C0204 phase decomposition into Co3O4 (c) 2008 Elsevier B.V. All rights reserved.

引用

页码：780 / 784

页数：5

共 8 条

[1] Thermal stability of LixCoO2 cathode for lithium ion battery [J].