关键词: 液流电池, 质子传导, 离子交换, 膜, 钒离子渗透

Abstract: Vanadium redox flow battery(VRB),which is regarded as one of the most promising devices for massive electricity storage in renewable energy and energy-saving processes,has attracted much attention,because of its long life-time,simple configuration and independent power and capacity ratings.Proton conductive membrane,one of key materials in VRB,performs the role of conducting protons during charge/discharge recycle,and prevents vanadium ions from direct contact between the positive and negative electrolytes.To achieve high energy efficiency,long life and low cost of VRB stack,the membrane should meet the requirements of high conductivity,chemical and mechanical resistance,low permeability of vanadium ions and acceptable cost.So far,Nafion membranes are generally employed in VRB due to their both high conductivity and chemical stability,however,their extremely high cost and poor ion selectivity have become the main barrier of commercialization of VRB.In this review,a detailed introduction about recent progress in the field of proton conductive membranes for VRB is given,including three aspects:(i)post-treated Nafion membranes to improve selectivity;(ii)non-perfluorinated membranes from polymerization and sulfonation of monomers; and(iii)nano-porous membranes based on difference between ion stokes radius and its valence,which provides selectivity for protons towards vanadium ions.Finally,there is a highlight of the relationship between morphology and performance of the advanced proton conductive membranes for research and development in future.

Key words: flow battery, proton conduction, ion exchange, membrane, vanadium ion permeation