Porous polybenzimidazole membranes with positive charges enable an excellent anti-fouling ability for vanadium-methylene blue flow battery  

作　　者：Dongju Chen Guangyu Liu Jie Liu Changkun Zhang Zhizhang Yuan 

机构地区：[1]School of Chemistry and Chemical Engineering,Liaoning Normal University,Huanghe Road 850,Dalian 116029,Liaoning,China [2]Division of Energy Storage,Dalian National Laboratory for Clean Energy,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,457 Zhongshan Road,Dalian 116023,Liaoning,China

出　　处：《Journal of Energy Chemistry》2022年第5期247-254,共8页能源化学（英文版）

基　　金：financial support from NSFC (22075121);the Youth Innovation Promotion Association CAS (2019182);the Dalian Science and Technology Innovation Project (2020JJ26GX031);the DNL Cooperation Found,CAS(DNL201910)。

摘　　要：A cost-effective, high-performance and highly stable membrane has always been in intensively needed in aqueous organic-based flow batteries. Here we present a porous polybenzimidazole(PBI) membrane with positive charges that endow the membrane with a high rejection and an excellent anti-fouling ability for target organic molecule and asymmetric structure that affords a high conductivity for vanadiummethylene blue flow battery(V-MB FB). The morphologies and thickness of separating layer in particular of the porous PBI can be well adjusted by simply altering the polymer concentration in the cast solution and further afford the membrane with a controllable property in terms of both ion selectivity and ion conductivity. As a result, a V-MB FB assembled with a porous PBI membrane delivers a coulombic efficiency(CE) of 99.45% and an energy efficiency(EE) of 86.10% at a current density of 40 mA cm^(-2), which is 12% higher than that afforded by a Nafion 212 membrane. Most importantly, the V-MB FB demonstrates a methylene blue(MB) utilization of 97.55% at a theoretical capacity of 32.16 Ah L^(-1)(based on the concentration of MB in the electrolyte) because of the high ion conductivity of the membrane, which favors reducing the cost of a battery. The results suggest that the designed porous PBI membranes exhibit a very promising prospect for methylene blue-vanadium flow battery.

关 键 词：Electrochemical energy storage technology Vanadium-methylene blue flow battery Porous PBI membranes Anti-fouling stability 

分 类 号：TM91[电气工程—电力电子与电力传动] TQ317[化学工程—高聚物工业]