Multiscale Observations of Inhomogeneous Bilayer SEI Film on a Conversion-Alloying SnO2 Anode
作者:
Lan, XX (Lan, Xuexia) [1] ; Cui, J (Cui, Jie) [2] ; Xiong, XY (Xiong, Xingyu) [1] ; He, JY (He, Jiayi) [1] ; Yu, HC (Yu, Hechuan) [1] ; Hu, RZ (Hu, Renzong) [1]
SMALL METHODS
卷5
期12
文献号2101111
DOI10.1002/smtd.202101111
出版时间DEC 2021
在线发表OCT 2021
已索引2021-11-08
文献类型Article
摘要
SnO2, storing Li through conversion and alloying reactions, has been regarded as one of the most typical anode materials and has been widely studied for both mechanism exploring and performance tuning. However, the structure of the solid electrolyte interphase (SEI) formed on the SnO2 electrode and its evolution process are rarely focused and still poorly understood. Herein, time of flight secondary ion mass spectrometry is used to observe the bilayer hybrid structure of SEI formed on a SnO2 film. Multiscale observations reveal the SEI accumulation after alloying reactions and distinct dissolving of the organic layer at potentials above de-conversion reactions, which results in the inorganic layer being directly exposed to the electrolyte and thus becoming thick and inhomogeneous. The broken and thick SEI causes rapid capacity decay and low Coulombic efficiencies (CEs) of 97.5%. Accordingly, it is demonstrated that, as the SnO2 is precoated with LiF or Li2CO3, a robust and thin SEI layer is induced to form and is stabilized in the continuous cycles, resulting in enhanced cycling stability and promoted CEs to 99.5%. This work adds new insights to the SEI evolution mechanisms on SnO2-based anodes and suggests an effective strategy to create high performance metal oxide anode for Li-ion batteries.
关键词
作者关键词Coulombic efficiencyinorganic layerssolid electrolyte interphasetime of flight secondary ion mass spectrometrytin dioxide
Keywords PlusSOLID-ELECTROLYTE INTERPHASEGRAPHITE ANODESLITHIUM METALBATTERIESSILICONDEGRADATIONPERFORMANCEMICROSCOPYEVOLUTIONSTORAGE
作者信息
通讯作者地址
Hu, Renzong
(通讯作者)
South China Univ Technol, Guangdong Prov Key Lab Adv Energy Storage Mat, Sch Mat Sci & Engn, Guangzhou 510640, Peoples R China
地址
1 South China Univ Technol, Guangdong Prov Key Lab Adv Energy Storage Mat, Sch Mat Sci & Engn, Guangzhou 510640, Peoples R China
2 South China Univ Technol, Analyt & Testing Ctr, Guangzhou 510640, Peoples R China
电子邮件地址msrenzonghu@scut.edu.cn
类别/分类
研究方向ChemistryScience & Technology - Other TopicsMaterials Science