期刊
ACS APPLIED MATERIALS & INTERFACES
卷 13, 期 36, 页码 42917-42926出版社
AMER CHEMICAL SOC
DOI: 10.1021/acsami.1c12882
关键词
lithium-ion batteries; 4.6 V LiCoO2; surface modification; hybrid ionic and electronic conductive layer; surface chemistry
资金
- National Natural Science Foundation of China [22075170, 52072233]
- Beijing Municipal Science and Technology Commission [Z191100004719001]
- Beijing National Laboratory for Condensed Matter Physics
A new coating layer was successfully applied on the LiCoO2 surface to improve its electrochemical performance under high cut-off voltage. This layer enhances the kinetics of ionic and electronic transport and acts as a protective barrier against side reactions between the cathode and electrolyte.
The LiCoO2 cathode undergoes undesirable electrochemical performance when cycled with a high cut-off voltage (>= 4.5 V versus Liar). The unstable interface with poor kinetics is one of the main contributors to the performance failure. Hence, a hybrid Li-ion conductor (Li1.5Al0.5Ge1.5P3O12) and electron conductor (Al-doped ZnO) coating layer was built on the LiCoO2 surface. Characterization studies prove that a thick and conductive layer is homogeneously covered on LiCoO2 particles. The coating layer can not only enhance the interfacial ionic and electronic transport kinetics but also act as a protective layer to suppress the side reactions between the cathode and electrolyte. The modified LiCoO2 (HC-LCO) achieves an excellent cycling stability (77.1% capacity retention after 350 cycles at 1C) and rate capability (139.8 mAh g(-1) at 10C) at 3.0-4.6 V. Investigations show that the protective layer can inhibit the particle cracks and Co dissolution and stabilize the cathode electrolyte interface (CEI). Furthermore, the irreversible phase transformation is still observed on the HC-LCO surface, indicating the phase transformation of the LiCoO2 surface may not be the main factor for fast performance failure. This work provides new insight of interfacial design for cathodes operating with a high cut-off voltage.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据