文献类型：期刊文献

英文题名：Influencing factors and behavior mechanism of the initial coulombic efficiency of silicon/graphite composites in lithium-ion batteries

作者：Gu, Zhiqiang[1];Li, Wenli[1];Miao, Yu[2];Chen, Yuxi[1];Xia, Xiaohong[1];Chen, Gairong[2];Liu, Hongbo[1,2]

第一作者：Gu, Zhiqiang

通讯作者：Liu, HB[1];Chen, GR[2]

机构：[1]Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China;[2]Xinxiang Univ, Coll Chem & Chem Engn, Xinxiang 453033, Henan, Peoples R China

第一机构：Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China

通讯机构：[1]corresponding author), Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China;[2]corresponding author), Xinxiang Univ, Coll Chem & Chem Engn, Xinxiang 453033, Henan, Peoples R China.|[110713]新乡学院化学化工学院;[11071]新乡学院;

年份：2021

卷号：366

外文期刊名：ELECTROCHIMICA ACTA

收录：;EI(收录号：20204709509318);Scopus(收录号：2-s2.0-85096185677);WOS:【SCI-EXPANDED(收录号:WOS:000596030500014)】；

基金：This work was supported by the joint project from the Henan-Provincial of National Natural Science Foundation of China (U1904189), National Natural Science Foundation of China (51772083, 51402101, 51472083), and Key R&D projects of Hunan Province (2018GK1030).

语种：英文

外文关键词：Initial coulombic efficiency; Specific surface area; Phase interface; Charge transfer impedance; Si/G composites

摘要：Investigating the internal factors that affect the initial coulombic efficiency (ICE) of silicon/graphite (Si/G) composites and improving ICE are critical to promote applications of Si/G composites in lithium-ion batteries. Here, four types of Si/G composites are prepared with different specific surface area, Si-G phase interface and charge transfer impedance (R-ct) to study the internal factors affecting the ICE of Si/G composites. The experimental results show that the influencing factors on ICE of Si/G composites are not only specific surface area, but also the Si-G phase interface and Rct. During the first lithiation process of Si/G composites, there are some reversible phase (LixSi, LixC) and irreversible phase (Li2O, Li2SiO4 and organolithium) formed, the ICE of Si/G composites is mainly determined by the irreversible phase. The specific surface area, Rct and Si-G phase interface can affect the reaction kinetics of the materials and the ratio of reversible/irreversible phase content, which ultimately affect the ICE of Si/G composites. A smaller specific surface area and well Si-G phase interface with a low Rct will bring a higher ICE of Si/G composites. This report may provide a new idea for the research of ICE of Si/G composites and promote their practical application. (c) 2020 Elsevier Ltd. All rights reserved.