采用丁二腈拓宽Li/CFx一次电池的使用温度范围
Succinonitrile broadening the temperature range of Li/CFx primary batteries
王宁 1罗振亚 1张庆丰 1潘俊安 1袁铜 1杨颖 2谢淑红1
作者信息
- 1. Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education,School of Materials Science and Engineering,Xiangtan University,Xiangtan 411105,China
- 2. Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials,Department of Physics,Hunan University of Science and Technology,Xiangtan 411201,China
- 折叠
摘要
在锂离子一次电池中,氟化碳(CFx)正极因具备高能量密度而广受关注.然而,低温下CFx正极的放电比容量急剧衰减.本研究采用丁二腈(SN)作为电解液添加剂,提高了−20℃ ～60℃宽温范围内的放电性能.实验结果表明,以0.5C倍率放电时,60℃、40℃、25℃、0℃、−10℃和−20℃的放电比容量分别是869.9 mA·h/g、801.9 mA·h/g、761.8 mA·h/g、527.3 mA·h/g、299.4 mA·h/g、140.7 mA·h/g,明显高于无添加剂的放电比容量792 mA·h/g、766.6 mA·h/g、723.6 mA·h/g、398.8 mA·h/g、207 mA·h/g、137.7 mA·h/g.由于丁二腈参与了固体电解质中间相的形成,有效地降低了电化学阻抗,加快了放电反应动力学,改善了电池的低温电化学性能.同时,SN改善了低温下电解液与隔膜之间的相容性,提高了Li+的迁移扩散速率.本研究提供了一种方便、低黏度的电解液体系,拓宽了Li/CFx一次电池在宽温域下的应用.
Abstract
In lithium primary batteries, fluorinated carbon (CFx) cathode has attracted enormous attention due to its high energy density. However, the CFx cathode reveals capacity fading sharply at low temperature. In this work, succinonitrile (SN) is used as an electrolyte additive to achieve excellent discharge performance at the temperature range from −20 ℃ to 60 ℃. The obvious enhancement of electrochemical performances is attributed to the participation of succinonitrile in the formation of solid electrolyte interphase, which reduces the electrochemical impedance of battery. It is found that the electrolyte with 10％ succinonitrile shows higher discharge platform and specific capacity at low temperature. Compared with the electrolyte without additive, the corresponding discharge capacity is enhanced from 398.8 mA·h/g to 527.3 mA·h/g at 0 ℃. This work provides a convenient and lower-viscosity electrolyte system to improve the Li/CFx primary batteries applications in widen-temperature.
关键词
Li/CFx一次电池/丁二腈/电解液/宽温域/放电比容量Key words
Li/CFx primary batteries/succinonitrile/electrolyte/wide temperature range/discharge capacity引用本文复制引用
基金项目
Hunan Innovation Team,China(2018RS3091)
National Natural Science Foundation of China(52202308)
National Natural Science Foundation of China(12105097)
Science and Technology Innovation Program of Hunan Province,China(2021RC2092)
出版年
2023
NETL
NSTL
维普
万方数据