Zeolite membrane separators for fire-safe Li-ion batteries – Effects of crystal shape and membrane pore structure
Zeolite membrane separators for fire-safe Li-ion batteries – Effects of crystal shape and membrane pore structure
复制标题
DOI：
10.1016/j.memsci.2023.121743
复制
发表时间：
2023-05
影响因子：
9.5
通讯作者：
Dheeraj Ram Lingam Murali;Fateme Banihashemi;Jerry Y. S. Lin
中科院分区：
文献类型：
--
作者：
Dheeraj Ram Lingam Murali;Fateme Banihashemi;Jerry Y. S. Lin
最先进的锂离子电池（LIB）使用碳酸盐基液体电解质和聚合物隔板，这带来了包括火灾危险在内的安全问题。使用阻燃盐浓缩电解质可以解决LIB的安全问题，但是这些电解质具有高粘度和与聚合物隔板的低润湿性，使得难以用电解质制造高性能LIB。在这里，我们报告的发展沸石膜分离器定制的孔结构和表面化学制备防火LIBs使用盐浓缩电解质。沸石膜分离器由具有特定沸石结构、Si/Al比和不同颗粒形状的沸石颗粒制成，通过可扩展的刮刀涂覆方法涂覆在阴极上。选择中孔、纯硅质MFI型沸石（silicalite）作为膜分离器的防火材料，该材料还为双（氟磺酰基）酰亚胺锂（LiFSI）在磷酸三甲酯溶剂（TMP）中的阻燃盐浓缩电解质提供高润湿性。采用低长径比（LAR）和高长径比（HAR）的板状硅分子筛颗粒在LiNi0.5Mn0.3Co0.2O2和NMC阴极上分别包覆两种孔径大小相似但孔隙率和弯曲度不同的硅分子筛膜隔膜。两种沸石隔板均显示出对LiFSI/TMP电解质的比商业聚丙烯（PP）隔板显著更好的润湿性，从而允许用不可燃硅质岩隔板制造高性能NMC/LiFSI-TMP/石墨电池。具有阻燃电解质的新型防火沸石膜基LIB表现出优异的充电和放电特性以及循环性能（类似于现有技术，但具有LiPF 6-碳酸盐电解质和聚合物隔板的防火不安全LIB）。显示出低颗粒间孔隙率和高曲折度的由HAR板状沸石制成的膜分离器比由LAR沸石颗粒制成的膜表现更好，这是由于来自分离器/阳极界面处的颗粒间孔和颗粒内沸石孔的更均匀的锂离子通量。
The state-of-the-art lithium-ion batteries (LIB) use carbonate-based liquid electrolytes and polymeric separators which pose safety issues including fire-hazard. The use of fire-retarding salt-concentrated electrolytes can address the safety issues of LIBs, but these electrolytes have high viscosity and low wettability with polymeric separators making it difficult to fabricate high performance LIBs with the electrolytes. Here we report development of zeolite membrane separators with tailored pore structure and surface chemistry for preparation of fire-safe LIBs using salt-concentrated electrolytes. The zeolite membrane separators are made of zeolite particles with a specific zeolite structure, Si/Al ratio, and different particle shapes, coated on cathode by a scalable blade coating method. Intermediate pore, pure silica MFI-type zeolite (silicalite) was selected as the fire-proof material for membrane separators which also offer high wettability for the fire-retarding salt-concentrated electrolyte of lithium bis(fluorosulfonyl)imide (LiFSI) in tri-methyl phosphate solvent (TMP) solvent. Two silicalite membrane separators of similar pore size but different porosity and tortuosity were coated on cathode (LiNi0.5Mn0.3Co0.2O2or NMC) using plate-shaped silicalite particles of low aspect ratio (LAR) and high aspect ratio (HAR). Both zeolite separators show significantly better wettability for the LiFSI/TMP electrolyte than the commercial polypropylene (PP) separator allowing fabrication of high-performance NMC/LiFSI-TMP/graphite cells with the non-combustible silicalite separator. The new fire-safe zeolite-membrane-based LIBs with the fire-retarding electrolyte exhibit excellent charge and discharge characteristics and cycle performance (similar to the state-of-the-art, but fire-unsafe LIBs with LiPF6-carbonate electrolyte and polymer separator). The membrane separators made of HAR plate-shaped zeolite showing low interparticle porosity and high tortuosity perform better than the membrane made of LAR zeolite particles, due to a more uniform lithium-ion flux from both interparticle pores and intraparticle zeolitic pores at the separator/anode interface.