辐照改性聚丙烯腈/热塑性聚氨酯锂离子电池隔膜的制备与性能
Preparation and properties of irradiated modified polyacrylonitrile/thermoplastic polyurethane lithium-ion battery separator
王一迪 1巩桂芬 1崔巍巍 1王召阳 1楼晨霞1
作者信息
- 1. 哈尔滨理工大学 材料与化学工程学院,哈尔滨 150040
- 折叠
摘要
聚丙烯腈(PAN)隔膜具有优秀的电化学性能,作为锂离子电池隔膜材料受到广泛关注,但其机械强度与耐热性不足问题依然存在.本文选用由软段与硬段构成的聚合物热塑性聚氨酯(TPU)与PAN进行混纺,并将制备的纤维膜通过60Co γ 射线对其改性,制备出一种新型锂离子电池隔膜.通过FTIR发现辐照改性PAN/TPU隔膜,PAN分子间出现环化反应,并且PAN与TPU分子间出现C=N-N键的交联,环和交联结构的引入都提高隔膜的力学与耐热性能,此外通过 100 kGy改性后的隔膜电化学性能优异,具有较高的吸液率(552%)与孔隙率(68.2%),电化学稳定窗口为 5.42 V,界面阻抗为 149.44 Ω,离子电导率为 1.68×10-3 S/cm,均优于辐照前的隔膜,1 C下循环100次后放电容量保持率为96.53%,并在循环测试中表现出优异的倍率性能.
Abstract
Polyacrylonitrile(PAN)separator has excellent electrochemical performance,and has been widely concerned as a lithium ion battery separator material,but its mechanical strength and heat resistance are still insufficient problems.In this paper,polymeric thermoplastic polyurethane(TPU)composed of soft segment and hard segment was blended with PAN,and the prepared fiber film was modified by 60Co γ to prepare a new type of lithium-ion battery separator.Through FTIR,it was found that the irradiation-modified PAN/TPU membrane had cyclization reaction among PAN molecules,and C=N-N bond crosslinking appeared between PAN and TPU molecules.The introduction of ring and crosslinking structures both improved the mechanical and heat resistance properties of the membrane.In addition,the membrane modified by 100 kGy had excellent electrochemical properties.It has a high electrolyte uptake(552%)and porosity(68.2%),an electrochemical stability window of 5.42 V,an interface impedance of 149.44 Ω,and an ionic conductivity of 1.68×10-3 S/cm,all of which are better than the separator before irradiation.After cycling 100 at 1 C,the discharge capacity retention rate is 96.53%.It also shows excellent magnification performance in cyclic test.
关键词
锂离子电池/电化学性能/隔膜/静电纺丝/聚丙烯腈/辐照Key words
lithium-ion batteries/electrochemical properties/separator/electrospinning/polyacrylonitrile/ir-radiation引用本文复制引用
出版年
2024