摘要
采用热重分析-傅里叶变换红外光谱法(TGA-FTIR)、差示扫描量热法(DSC)和X射线衍射光谱法(XRD)对锂离子电池中石墨负极材料在热失控和热爆炸中的反应机理进行了系统的研究和探讨。研究表明,石墨表面在最初循环中形成的原始固体电解质(SEI)膜具有热不稳定性,在t>70℃时开始分解。而失去了原始SEI膜保护,会导致石墨中嵌入锂和其表面电解液的接触,在高温时形成二次电解质膜。详细讨论了石墨中嵌入锂的数量和石墨颗粒的结构、形状及其层状结构边缘的比表面对二次电解质膜形成的影响。
The reaction mechanism of graphite anode for Li-ion battedes during thermal runaway and thermal explosion was studied with thermogravimetric analysis （TGA） and on-line Fourier transform infrared （FTIR）, differential scanning calodmetry （DSC） and X-ray diffraction （XRD）. Research showed that the solid electrolyte interface （SEI） formed in the initial cycle was unstable, which would decomposed above 70 ℃. Hence, without the protection of SEI film, the intercalated lithium reacted with the electrolytes to form a secondary SEI film at high temperature. The influence of the graphite structure, shape, amount of lithiated graphite and the BET of the edge of layered structure on the formation of secondary SEI film was discussed.
出处
《电源技术》
CAS
CSCD
北大核心
2009年第10期879-883,共5页
Chinese Journal of Power Sources
基金
江苏省自然科学基金项目(BK200718)
关键词
锂离子电池
负极材料
脱锂程度
SEI膜
热稳定性
lithium batteries
anode material
delithiated degree
solid electrolyte interface
thermal stability
