Sulfonated poly(phthalazinone ether sulfone) membrane as a separator of vanadium redox flow battery

Abstract

To develop a novel and low-cost membrane as a separator of vanadium redox flow battery, sulfonated poly (phthalazinone ether sulfone) (SPPES) was prepared by sulfonating PPES with fuming sulfuric acid. By testing the sulfonation degree, intrinsic viscosity, and solubility of SPPES, the results showed that sulfonated polymers had higher intrinsic viscosities and excellent solubility in most polar solvents. IR analysis revealed that the -SO 3 H group was successfully attached to SPPES backbone. DSC and TG results showed that SPPES exhibited higher T g than that of PPES, and T d at the first weight loss of SPPES was about 300°C. The SPPES membrane (SP-02) showed a dramatic reduction in crossover of vanadium ions across the membrane compared with that of the Nafion membrane. Cell tests identified that VRB with the SPPES membrane exhibited a lower self-discharge rate, higher coulombic efficiency (92.82%), and higher energy efficiency (67.58%) compared with the Nafion system. Furthermore, cycling tests indicated that the single cell with SPPES membrane exhibited a stable performance during 100 cycles.

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

“…The lower the SW, the better the dimensional stability is. Though SW of SPI membranes (15.51 -18.11%) are higher than Nafion 117 membrane (11.40%), these SW values of SPI membranes are still acceptable in VRB applications just like other non-fluorinated polymer membranes such as SPEEK [10] and SPPES [12], etc. Table 2 shows the proton conductivity of SPI membranes and Nafion 117 membrane.…”

“…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.…”

The Structure–Activity Relationship in Membranes for Vanadium Redox Flow Batteries

“…ether ketone) (SPEEK), [32] SPAEK, [33] sulfonated poly (arylene ether sulfone) (SPES), [32c,34] sulfonated poly(sulfone) (SPSF), [35] sulfonated Diels Alder poly(phenylene) (SDAPP), [36] sulfonated poly(phthalazinone ether sulfone) (SPPES), [37] sulfonated poly (-phthalazinone ether ketone) (SPPEK), [38] sulfonated poly(phenylene oxide) (SPPO), [39] sulfonated polyimide (SPI), [40] sulfonated poly(arylene thioether ketone) (SPTK), [41] sulfonated poly(arylene thioether ketone ketone) (SPTKK), [41] and sulfonated poly (fluorenyl ether ketone) (SPFEK). [42] The degrees of sulfonation (DS) shows a remarkable influence on ions transfer, water uptake and mechanical stability of sulfonated aromatic polymers via changing the microstructure of polymers.…”

Hybrid membranes with low permeability for vanadium redox flow batteries using in situ sol-gel process

“…Currently, perfluorinated sulfonic acid polymers, i.e., Nafion, are widely used as membranes in VRFBs due to their good performance and durability. However, Nafion is permeable to vanadium ions and their crossover exhibits ion depletion for redox reactions, which reduces their efficiency and capacity [9]. Toreduce vanadium ion permeability, a significant amount of research has focused on sulfonated aromatic polymer membranes [10][11][12][13][14][15].…”