Chung, Kyung Yoon Yoon, Won-Sub McBreen, James Yang, Xiao-Qing Oh, Si Hyoung Shin, Ho Chul Cho, Won Il Cho, Byung Won 2024-01-21T02:04:17Z 2024-01-21T02:04:17Z 2021-09-02 2006-11 0013-4651 https://pubs.kist.re.kr/handle/201004/134988 The effects of ZrO2-coating on the surface of LiCoO2 have been studied using synchrotron-based in situ x-ray diffraction (XRD) technique. Although both ZrO2-coated LiCoO2 and uncoated LiCoO2 showed capacity fading during high voltage (4.8 V) cycling, the ZrO2 coated one showed better cycle performance. After observing capacity fade for both samples through 10 charge-discharge cycles, in situ XRD patterns were collected during the 11th charge with reduced current density. With reduced current density, both samples restored part of their lost capacity. However, in situ XRD data shows that the ZrO2-coated LiCoO2 sample has much better structural change behaviors than the uncoated LiCoO2. The partial restoration of the lost capacity and the recovered structural variations observed at reduced current density clearly indicates that the lost capacity is very closely related to the increased polarization, which is most likely due to the precipitation of the electrolyte decomposition products on the surface of LiCoO2 cathode material. ZrO2 coating layer may provide some protection for the LiCoO2 cathode surface and help to reduce the electrolyte decomposition at higher voltages. (c) 2006 The Electrochemical Society. English ELECTROCHEMICAL SOC INC CATHODE PHASES Structural studies on the effects of ZrO2 coating on LiCoO2 during cycling using in situ X-ray diffraction technique Article 10.1149/1.2338661 1 JOURNAL OF THE ELECTROCHEMICAL SOCIETY, v.153, no.11, pp.A2152 - A2157 JOURNAL OF THE ELECTROCHEMICAL SOCIETY 153 11 A2152 A2157 scie scopus 000241057000022 2-s2.0-33749648440 Electrochemistry Materials Science, Coatings & Films Electrochemistry Materials Science Article CATHODE PHASES LiCoO2 ZrO2 coating Capacity Fading Lithium Secondary Batteries Cathode in situ X-ray diffraction