废旧锂电池电极活性材料真空热解固氟研究

Vacuum Pyrolysis of Fluoride Retention in Electrode Active Material of Lithium Ion Battery

以废旧锂离子电池电极活性材料为研究对象,在真空热解过程中加入CaO作为固氟剂,用以吸收电极活性材料在真空热解的回收工艺中产生的氟磷化合物,能有效减轻二次污染。研究了温度、CaO添加量、停留时间等热解条件对真空热解固氟效果的影响。结果表明固氟效果随温度的增加而增加,在温度500℃以上变化不大,并略有下降;CaO添加量对固氟效果有促进作用,30%可达到很高的固氟效果;30 min的停留时间对于含氟化合物的分解已经足够。得到CaO固氟工序的最佳操作参数：CaO添加量30%左右,温度500~600℃,停留时间30 min。

With electrode active materials of lithium ion batteries（LIBs）as research objects,CaO as a fluoride retention additive in the vacuum pyrolysis process,fluoride phosphorus compounds produced in the vacuum pyrolysis of electrode active materials can be effectively absorbed,which would reduce the secondary pollution.Effects of pyrolysis conditions such as pyrolysis temperature,CaO addition and residence time on fluoride retention were investigated.Results showed that effects of fluoride retention increased with temperature,and effect of fluoride retention changed a little and slightly decreased above 500 ℃.CaO addition is helpful to fluoride retention,with 30% of addition quantity to a satisfactory result.30min residence time for fluoride and phosphorus compound decomposition is sufficient.The optimum conditions of fluoride and phosphorus retention by CaO were 30% CaO addition quantity,temperature 500~600 ℃ and residence time 30 min.