Autor: |
Mingwei Zan, Hongsheng Xie, Sichen Jiao, Kai Jiang, Xuelong Wang, Ruijuan Xiao, Xiqian Yu, Hong Li, Xuejie Huang |
Jazyk: |
angličtina |
Rok vydání: |
2024 |
Předmět: |
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Zdroj: |
Small Science, Vol 4, Iss 10, Pp n/a-n/a (2024) |
Druh dokumentu: |
article |
ISSN: |
2688-4046 |
DOI: |
10.1002/smsc.202400162 |
Popis: |
Lithium cobalt oxide (LiCoO2) is an irreplaceable cathode material for lithium‐ion batteries with high volumetric energy density. The prevailing O3 phase LiCoO2 adopts the ABCABC (A, B, and C stand for lattice sites in the close‐packed plane) stacking modes of close‐packed oxygen atoms. Currently, the focus of LiCoO2 development is application at high voltage (>4.55 V versus Li+/Li) to achieve a high specific capacity (>190 mAh g−1). However, cycled with a high cutoff voltage, O3–LiCoO2 suffers from rapid capacity decay. The causes of failure are mostly attributed to the irreversible transitions to H1‐3/O1 phase after deep delithiation and severe interfacial reactions with electrolytes. In addition to O3, LiCoO2 is also known to crystalize in an O2 phase with ABAC stacking. Since its discovery, little is known about the high‐voltage behavior of O2–LiCoO2. Herein, through systematic comparison between electrochemical performances of O3 and O2 LiCoO2 at high voltage, the significantly better stability of O2–LiCoO2 (>4.5 V) than that of O3–LiCoO2 in the same micro‐sized particle morphology is revealed. Combining various characterization techniques and multiscale simulation, the outstanding high‐voltage stability of O2–LiCoO2 is attributed to the high Li diffusivity and ideal mechanical properties. Uniform Li+ distribution and balanced internal stress loading may hold the key to improving the high‐voltage performance of LiCoO2. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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