摘要
利用绝热加速量热仪对商业锂离子电池中常用的3种电解液进行了热分析实验,并根据测试结果评价了其热安全性。3种电解液的初始反应温度均在180～2 0 0℃之间;运用绝热理论模型,得到3种电解液热分解反应的活化能Ea 分别为(2 46.2 0 2±2 .866) k J·mol- 1 、(2 77.94±7.49) k J·mol- 1 和(778.81±3 4.86) k J·mol- 1 ;每克样品反应终止时压力分别达到2 173 .84k Pa、2 0 74.80 k Pa和240 8.65 k Pa,压力升高值△P分别为:819.42 k Pa、1619.3 7k Pa和80 8.5 4k Pa。
This paper introduces the author's adiabatic thermal analysis of 1 mol·L^(-1) solutions of LiPF_6 with ethylene carbonate (EC) + diethyl carbonate (DEC) + dimethyl carbonate (DMC) (1:1:1 in mass), EC+ DMC(1:1 in mass)and EC+DEC(1:1 in mass)Electrolytes frequently used in lithium ion battery. The thermal safety of Electrolytes is assessed then according to the results of tests. The initial temperatures of decomposition reaction of these three electrolytes are respectively 182.26 ℃, 181.95 ℃and 196.47 ℃. Based on the adiabatic theory model, the activation energies of the decomposition reactions are calculated respectively, which are (246.20±2.87) kJ·mol^(-1), (217.81±2.51) kJ·mol^(-1) and (778.81±34.86) kJ·mol^(-1). The time for getting to the maximum rate of temperature rise is another value to show how drastic the reaction is, which obtained here are 13.33 min, 14.47 min and 5.76 min. The adiabatic temperature rise of these three electrolytes is 114.91 ℃, 106.86 ℃ and 22.37 ℃ respectively. The final pressures of 1 gram of above-mentioned three samples when decomposition reactions finished are 2 173.84 kPa, 2 074.80 kPa and 2 408.65 kPa, and the improvement of pressure, △P, are 819.42 kPa, 1 619.37 kPa and 808.54 kPa, respectively.
出处
《安全与环境学报》
CAS
CSCD
2005年第2期106-111,共6页
Journal of Safety and Environment
关键词
物理化学
电解液
加速量热仪(ARC)
热安全性
活化能
physical chemistry
electrolyte
accelerating rate calorimeter (ARC)
thermal safety
activation energy
