基于ATRP反应的钒电池用聚砜两性离子交换膜的设计、制备及性能机制研究

钒电池是一种新型高效的大规模储能系统，隔膜是其关键材料之一。离子交换膜是当前钒电池中最常用的隔膜材料。阳离子或阴离子交换膜单独用于钒电池时都存在一定的缺陷，其中阳离子膜的钒渗透率和水渗透率偏高，而阴离子膜的电导率和稳定性偏低。为此，本课题拟采用性能优异的高聚物材料聚砜(PSF)作为基体，借助均相体系下的原子转移自由基聚合(ATRP)反应在PSF本体上接枝不同结构、链长或比例的两性官能团，设计和制备同时具有高电导率和高阻钒率的新型两性离子膜，系统深入研究两性膜中不同电性离子/分子传输机制，揭示不同结构和组成两性离子膜微观结构、物化参数与电池性能之间的构效关系，为进一步研制VRB用新型、高效非氟离子膜提供科学依据。

Vanadium flow battery (VRB) is a novel large scale energy storage system with high efficiencies. Membrane is one of the key materials for VRB and ion exchange membranes are the most commonly used separator in VRB application at present. There are some disadvantages for cation exchange membrane (CEM) and anion exchange membrane (AEM) when they are applied in VRB. For example, CEM has high vanadium/water permeability and AEM exhibits low proton conductivity/stability. Consequently, in order to solve the problem, a novel amphoteric ion membrane aiming to obtain both high conductivity and low vanadium permeability is designed and prepared. The project adopts polymer material polysulfone (PSF) with excellent performance as the matrix. By means of atom transfer radical polymerization (ATRP) reaction under homogeneous phase, the amphoteric functional groups with different structure, chain length or proportion will be grafted onto the PSF body. The transportation mechanism of different ionic/water across amphoteric membranes will be studied systematically in order to reveal the structure-activity relationship between the cell performance and microstructures, physiochemical parameters of amphoteric membranes with different structure and compositions. The study will provide a scientific help for the further design and preparation of novel and high efficiency non-fluoride membranes for VRB application.