摘要
静电纺丝纳米纤维膜作为锂离子电池隔膜使用时具有优良的性能,但是由于纤维间抱合力较小,强度较低,其应用受到了极大限制。通过耐高温相PAN与低熔点相PVDF两种聚合物混纺,并经过适当的热压后处理,使PVDF部分熔融形成点粘结,制备PAN-PVDF复合纳米纤维膜,并测试其相关性能。发现在保留静电纺膜优良性能的前提下,其强度相对处理前提高了近10倍,并表现出良好的电化学性能:室温下离子电导率达到1.32×10-3S/cm,聚合物电解质分解电压高达5.24 V,界面阻抗仅为45Ω,0.2 C首次放电比容量高达152 m Ah/g,综合性能远优于美国CELGARD2400。
The electrospun nanofiber membrane had excellent performance when used as separator of Li-ion battery. Its applications were limited due to the low cohesive force between single nanofibers and the low strength of the electrospun membrane. The PAN-PVDF electrospun membrane was prepared by blended electrospinning with thermostable phase PAN and low melting temperature phase PVDF. PVDF was melted partially to form point bonding after proper thermal calendering process and its relevant properties were measured. The results show that the strength of the modified membrane is almost 10 times higher than that of as-spun electrospun membrane. The improvements in electrochemical properties of the electrospun samples were also observed in this study such as, （1） ionic conductivity at room temperature was 1.32 x 10-3 S/cm; （2） electrochemical stability potential was 5.24 V; （3） interface impedance between the membrane andthe electrodes was 45 Q ; and （4） the initial discharge capacity was 152 mAh/g under 0.2 C ratio. Therefore, the comprehensive properties of the modified membrane were superior to that of CELGARD 2400.
出处
《电源技术》
CAS
CSCD
北大核心
2014年第12期2231-2234,2238,共5页
Chinese Journal of Power Sources
基金
国家自然科学基金项目(51373121)
