Quaternized poly(phthalazinone ether ketone ketone) anion exchange membrane with low permeability of vanadium ions for vanadium redox flow battery application

Poly(phenyl sulfone) anion exchange membranes with pyridinium groups for vanadium redox flow battery applications

“…Swelling of membrane is an important issue for VRFB stacks because membrane stability affected by scaling in membrane size [36]. However, very limited data is reported that the swelling ratio of membranes in vanadium electrolyte [21,28]. In this work, the swelling ratios of membrane in deionized water as well as in 1.5 M VOSO 4 in 3 M H 2 SO 4 were investigated.…”

“…The ion exchange capability (IEC) of membrane was determined by titration [21]. A dried PyPPSU membrane (in chloride form) was obtained under vacuum at 60 C for 48 h, and then it was weighed and immersed in 25 mL 0.1 mol L À1 NaNO 3 solution for 48 h at room temperature.…”

Low vanadium ion permeabilities of sulfonated poly(phthalazinone ether ketone)s provide high efficiency and stability for vanadium redox flow batteries

“…The corresponding mechanical stability of the immersed membrane was measured using an Instron 5567 instrument. The permeation of VO 2þ and V 3þ through the membranes was evaluated by methods reported previously [22]. The V 3þ solution was prepared by the electrochemical reduction of the VO 2þ solution and the membrane was sandwiched between two half-cells.…”

“…Recently, our research group has reported several kinds of aromatic phthalazinone-containing polymers, such as quaternized poly(phthalazinone ether ketone) [20], quaternized poly(-phthalazinone ether sulfone) [21] and quaternized poly(-phthalazinone ether ketone ketone) [22], which were used as anion exchange membranes. These polymers with rigid unsymmetrical phthalazinone moieties [23] showed favorable cell performance in VRFB systems.…”

Sulfonated polyimide membranes with different non-sulfonated diamines for vanadium redox battery applications

“…But the high vanadium ion permeability and cost limit their large scale applications. So far, sulfonated aromatic polymer membranes, such as sulfonated poly(ether ether ketone) (SPEEK) [10], sulfonated poly(phenylsulfone) (S-Radel) [11], sulfonated poly(phthalazinone ether sulfone) (SPPES) [12], chloromethylated poly(phthalazinone ether ketone) (CMPPEK) [13], and quaternized poly(phthalazinone ether ketone ketone) (QAPPEKK) membranes [14] have been attracted high attention due to their lower vanadium ion permeability, better proton selectivity, more excellent VRB performance and lower cost compared with Nafion membrane. However, these pristine sulfonated aromatic polymer membranes are commonly doubted by their less durability than Nafion in VRB.…”