Sarkar Amrita, May Richard, Ramesh Sapna, Chang Wesley, Marbella Lauren E
Department of Chemical Engineering, Columbia University, New York, NY 10027, USA.
Department of Chemistry and Biochemistry, Montclair State University, Montclair, NJ 07043, USA.
ChemistryOpen. 2021 May;10(5):545-552. doi: 10.1002/open.202100060.
Here, we investigate the recovery and reuse of polyvinylidene fluoride (PVDF) binders from both homemade and commercial cathode films in Li ion batteries. We find that PVDF solubility depends on whether the polymer is an isolated powder or cast into a composite film. A mixture of tetrahydrofuran:N-methyl-2-pyrrolidone (THF : NMP, 50 : 50 v/v) at 90 °C delaminates composite cathodes from Al current collectors and yields pure PVDF as characterized by H nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), wide-angle X-ray scattering (WAXS), and scanning electron microscopy (SEM). PVDF recovered from Li ion cells post-cycling exhibits similar performance to pristine PVDF. These data suggest that PVDF can be extracted and reused during Li ion battery recycling while simultaneously eliminating the formation of HF etchants, providing an incentive for use in direct cathode recycling.
在此，我们研究了从锂离子电池的自制和商用阴极薄膜中回收和再利用聚偏氟乙烯（PVDF）粘合剂的方法。我们发现PVDF的溶解度取决于该聚合物是呈孤立粉末状还是被制成复合薄膜。在90°C下，四氢呋喃与N-甲基-2-吡咯烷酮的混合物（THF : NMP，体积比50 : 50）能使复合阴极与铝集流体分层，并得到纯PVDF，这通过氢核磁共振（NMR）、凝胶渗透色谱法（GPC）、广角X射线散射（WAXS）和扫描电子显微镜（SEM）得以表征。从循环后的锂离子电池中回收的PVDF表现出与原始PVDF相似的性能。这些数据表明，PVDF可在锂离子电池回收过程中被提取并再利用，同时消除HF蚀刻剂的形成，这为其用于直接阴极回收提供了动力。
