Qiao Lin, Liu Shumin, Cheng Haodong, Ma Xiangkun
Department of Materials Science and Engineering, Dalian Maritime University, Dalian 116026, China.
Department of Materials Science and Engineering, Hunan University, Changsha 410082, China.
Membranes (Basel). 2022 Mar 31;12(4):388. doi: 10.3390/membranes12040388.
Vanadium flow battery (VFB) is one of the most promising candidates for large-scale energy storage. A modified polyacrylonitrile (PAN) porous membrane is successfully applied in VFB. Herein, a simple solvent post-processing method is presented to modify PAN porous membranes prepared by the traditional nonsolvent induced phase separation (NIPS) method. In the design, polymer PAN is chosen as the membrane material owing to its low cost and high stability. The large-size pores from NIPS method are well optimized by the solvent swelling and shrinking during the solvent post-processing. Meanwhile, the interconnectivity of pores is maintained well. As a result, the ion selectivity of PAN porous membranes is dramatically improved, and the CE of a VFB with PAN porous membranes rises from 68% to 93% after the solvent post-processing process. A VFB with the modified PAN porous membranes is capable of delivering a limiting current density of 900 mA cm, and a high peak power density of 650 mW cm, which is very competitive among the various flow batteries.
钒液流电池（VFB）是大规模储能最有前景的候选者之一。一种改性聚丙烯腈（PAN）多孔膜成功应用于钒液流电池。在此，提出了一种简单的溶剂后处理方法来改性通过传统非溶剂诱导相分离（NIPS）法制备的PAN多孔膜。在该设计中，选择聚合物PAN作为膜材料，因其成本低且稳定性高。通过溶剂后处理过程中的溶剂溶胀和收缩，对NIPS法产生的大尺寸孔隙进行了优化。同时，孔隙的连通性得到了很好的保持。结果，PAN多孔膜的离子选择性显著提高，经过溶剂后处理后，使用PAN多孔膜的钒液流电池的库仑效率从68%提高到了93%。具有改性PAN多孔膜的钒液流电池能够提供900 mA/cm的极限电流密度和650 mW/cm的高峰值功率密度，这在各种液流电池中具有很强的竞争力。
