废锂离子电池中集流体与活性物质的分离

针对废旧锂离子电池回收工艺中电极集流体的分离问题,根据集流体、活性物质、粘结剂的物理化学性质差异,对高温焙烧法、物理擦洗法和稀酸浸出-搅拌擦洗法分离集流体与活性物质进行研究。结果表明：高温焙烧与物理擦洗法都不能完全使集流体分离出来,而通过稀酸溶解-搅拌擦洗联合作用分离效果良好,在硫酸浓度为0.5 mol/L、固液比1：10、搅拌速度200 r/min、反应时间为40 min的条件下,可以实现正负极活性物质与集流体的分离,铝箔和铜箔可直接作为产品回收,只有极少部分进入浸出液,浸出渣用硫酸再浸,可以使钴、锂全部溶出,净化除杂后可回收钴和锂。

Separation of current collectors and active materials from spent lithium-ion secondary batteries

The separation and recovery of valuable metals from spent lithium-ion battery were investigated.Based on different physical and chemical properties among the current collectors,active materials and binder,three methods,high-temperature calcination,stirring scrubbing and dilute acid leaching with stirring scrubbing,were used to study the separation of active materials from current collectors.Factors influencing this process such as leaching concentration,reaction time and the ratio of liquid to solid were studied.The results show that the high-temperature calcination and stirring scrubbing are invalid because the current collectors and active materials can not be separated.The dilute acid leaching with stirring scrubbing is the most optimum method.The optimum separation can be obtained in 0.5 mol/L sulfuric acid solution with ratio of liquid to solid of 1?10,and stirring at 200 r/min for 40 min at room temperature.The active materials containing LiCoO2 and C are leached out by H2SO4 and can be used for the further recovery of cobalt and lithium.The aluminum foil and copper foil are obtained as product by cleaning current collectors.