【摘要】 以铝箔为基材,在磷酸–硫酸混合溶液中采用直流阳极氧化法进行表面处理,使铝箔表面形成多孔氧化铝结构。采用粘附力测试、扫描电镜、循环伏安、电化学阻抗谱、恒流充放电等方法,对铝箔表面结构及以其作为正极集流体的锂离子电池充放电性能进行考察。结果表明,经过阳极氧化处理的铝箔表面形成孔径为1~5μm的多孔氧化铝层,使活性材料的粘附力提高了23%,在1 mol/L LiP F6的碳酸甲乙酯和碳酸乙烯酯电解液体系中的耐腐蚀性能得到明显提升。未处理铝箔的腐蚀电流密度峰值为0.267 mA/cm2,阳极氧化处理后降至0.022 m A/cm2。经过200次充放电循环后,0.5 C、1 C和5 C倍率下采用经阳极氧化处理铝箔的锂离子电池比容量比采用未处理铝箔的电池比容量分别高2.85%、4.42%和10.56%。更多还原

【Abstract】 A porous alumina film was formed on the surface of aluminum foil by direct-current anodizing in a sulfuric– phosphoric acid electrolyte. The structure of the anodized aluminum foil and charge–discharge performance of the Li-ion battery which is prepared with it as current collector were characterized by adhesion test, scanning electron microscopy(SEM), cyclic voltammetry, electrochemical impedance spectroscopy, and constant current charge–discharge method. The pore size of the porous alumina film formed on aluminum foil is 1-5 μm. The adhesion between active material and aluminum current collector is improved by 23% after anodization. The corrosion current density peak of aluminum foil in ethyl methyl carbonate + ethylene carbonate electrolyte containing 1 mol/L LiP F6 is reduced from 0.267 mA /cm2 to 0.022 mA /cm2 after surface anodization, indicating that anodization greatly improves the corrosion resistance of aluminum foil. The specific capacity of Li-ion battery using the anodized aluminum foil as current collector is increased by 2.85% at 0.5 C, 4.42% at 1 C, and 10.56% at 5 C as compared with that of Li-ion battery using untreated aluminum foil after 200 charge–discharge cycles.更多还原