Al2O3/PVdF无纺布锂离子电池隔膜的制备及性能表征（英文）

Al2O3/PVdF-coated Nonwoven Separator for Lithium-ion Battery: Development and Characterization

采用N-甲基吡咯烷酮(NMP)做为溶剂,PVdF作有机相粘结剂制备出含Al2O3颗粒的均匀浆料,并通过简单浸渍法将浆料均匀地涂覆在无纺布基底两侧,干燥制得Al2O3/PVdF无纺布复合隔膜。研究不同Al2O3/PVdF比例复合隔膜样品的表面形貌、孔径分布、热稳定性、浸润性和循环充放电等性能,并分别与原无纺布基底材料以及商用Celgard 2300隔膜进行对比。研究结果表明,相比于基底材料,CS-5复合隔膜样品(Al2O3/PVdF(5/5wt%))表面形成亲液多孔结构,孔径集中分布在0.1μm左右,孔隙率从68.79%提高到75.83%,保液率由172%提高到487%;对比于商用Celgard 2300隔膜,CS-5隔膜在150℃下几乎没有发生热收缩,对电解液具有更优异的浸润性。由CS-5隔膜组装的电池,在100mA·g^-1充放电倍率下经过100次循环后,放电比容量最高,稳定在512mA·g^-1左右。

Al2O3/PVdF-coated nonwoven separators were successfully developed by coating a homogeneous slurry with different weight ratios of Al2O3 particles and PVdF binder.The morphology,pore size distribution,thermal stability,wettability,and electrochemical properties of the composite Al2 O3/PVdF/nonwoven separators,the nonwoven and commercial Celgard 2300 separator were analyzed.The results show that the CS-5 separator(Al2O3/PVdF(5/5 wt%)),compared to the nonwoven,develops a hydrophilic porous structure,the pore size is around 0.1μm,the porosity increases from 68.79% to 75.83%,and the electrolyte uptake increases from 172% to487%;In comparison with the Celgard 2300 separator,the CS-5 separator exhibits excellent thermal stability with almost no thermal shrinkage at 150℃,and enhanced electrolyte wettability.Additionally,the battery assembled with CS-5 separator exhibits the highest specific capacity of512 mA·g^-1 and good cycling performance after 100 charge-discharge cycles at a current density of 100 mA·g^-1.