废锂电池破碎及碱浸除铝特性

Shear Breaking and Al Removing by Alkaline Leachate for Spent Lithium Batteries

从工业生产出发,以废旧锂离子电池为实验对象,研究了机械破碎对正负极材料筛分富集的影响,利用XRD、SEM和ICPAES等考察了各因素对碱法去除废旧锂离子电池正负极材料富集体中Al的影响,并进行放大实验研究。结果表明:≤0.5 mm物料(46.77 wt.%)主要成分为LiCoO_2和乙炔黑以及部分铝和铜,正负材料基本全部进入此部分物料中;0.5～2、2～5 mm物料主要成分为Cu箔、Al箔、金属外壳和塑料薄膜,分别占16.62 wt.%和25.54 wt.%。当NaOH浓度12 wt.%、液固比20:1时,50℃下反应3 h后,100 Hz超声1 h,实验室放大实验表明Al的去除率达到86.34%;XRD及SEM结果显示实验原料主要成份为Li_2CoO_2和C,碱浸后Al的含量显著降低。

From the standpoint of industrial production, using spend Li-ion batteries as the raw materials, the effect of shear breaking on the enrichment of positive and negative materials was investigated, the effect of all the factors that affect alkaline leaching process for removing Al from the enriched positive and negative materials of spend li-ion batteries were examined by X-ray diffraction(XRD), scanning electron microscopy(SEM) and inductive coupled plasma emission spectrometer-atomic emission spectrometer(ICP-AES), and the enlarged experiment was conducted based on the laboratory experiments. The re-sults indicated that the materials(≤ 0.5 mm), accounting for 46.77 wt.%, were mainly composed by LiCoO_2, C and partly by Al and Cu. Positive and negative materials of the spent li-ion batteries were almost all enriched in ≤0.5 mm. The main phases 0.5~2 mm and 2~5 mm, accounting for 16.62 wt.% and 25.54 wt.% respectivily, were Cu foil, Al foil, metal shell and plastic film. According to the enlarged experiment, which was conducted at theoptimum condition: 12 wt.% Na OH, 50 ℃, 3 h 20:1 of liquid/solid 100 Hz of ultrasonic frequency, Al removing rate was up to 86.34%. XRD spectrum and SEM images indicated that the main phase of raw materials was LiCoO_2 and C. The content of aluminum was reduced significantly after alkali leach-ing.