Semi-Interpenetrating Network-Type Cross-Linked Amphoteric Ion-Exchange Membrane Based on Styrene Sulfonate and Vinyl Benzyl Chloride for Vanadium Redox Flow Battery

Abstract

Clean energy is the main requirement for human life. Redox flow battery may be an alternative to fossil fuels. An ion-exchange membrane is the heart of the redox flow battery. In the present study, we synthesize semi-interpenetrating cross-linked copolymer amphoteric ion-exchange membranes (AIEMs) with a partially rigid backbone. The styrene sulfonate and vinyl benzyl chloride monomers are used as the cationic and anionic moieties into the AIEMs. Three different types of quaternizing agents are used to convert a primary amine into a quaternary amine group. Here, we avoid the use of the carcinogenic chemical CMME, commonly used for the synthesis of anion-exchange membranes. The prepared membranes exhibit good electrochemical and physicochemical properties with a high acidic stability. The membranes also show moderate water uptake and dimensional change. The ZWMO membrane shows better properties among the AIEMs, with an ionic conductivity of 3.12 × 10 –2 S cm –1 and 5.49 water molecules per functional group. The anion and cation-exchange capacities of the ZWMO membranes are calculated to be 1.11 and 0.62 mequiv/g. All AIEMs show good thermal and mechanical stabilities, calculated by differential scanning calorimetry, dynamic mechanical analysis, and universal testing machine analysis. The membranes show low vanadium ion permeability than the commercial membrane Nafion for their use in vanadium redox flow batteries. Further, the AIEMs are applied in redox flow batteries as separators and deliver good results with the charging and discharging phenomena, with 87% voltage efficiency and 91% current efficiency.

Styrene-co-DVB grafted PVDF proton exchange membranes for vanadium redox flow battery applications

“…The redox couples are VO 2 + /VO 2+ and V 3+ /V 2+ in the anolyte and catholyte compartment, respectively. 17 The IEMs required for VRFB should possess good mechanical and chemical stability, together with good proton conductivity and low crossover of vanadium ions. 18,19 Nafion is the state-of-the-art membrane used for redox flow batteries possessing good proton conductivity and mechanical stability.…”

Amphoteric Membranes Based on Sulfonated Polyether Ether Ketone and Imidazolium‐Functionalized Polyphenylene Oxide for Vanadium Redox Flow Battery Applications

“…In an amphiphilic membrane, the penetration of vanadium ions can be effectively resisted by the cationic groups due to their Donnan exclusion effect, while the anionic groups (sulfonate groups) ensure the high conductivity of membranes. The results reported in the previous papers showed that the amphoteric membranes are good prospects for VRFB applications …”

Ionizing Radiation for Preparation and Functionalization of Membranes and Their Biomedical and Environmental Applications

“…Other types of CEMs containing sulfonic acid groups were developed due to their excellent proton conductivity and their mechanical and chemical stabilities. However, a high degree of sulfonation is required to obtain high conductivity, which often leads to high swelling ratio and reduced mechanical stability [123].…”

“…Other types of CEMs containing sulfonic acid groups were developed due to their excellent proton conductivity and their mechanical and chemical stabilities. However, a high degree of sulfonation is required to obtain high conductivity, which often leads to high swelling ratio and reduced mechanical stability [123]. This year (2019), Cui, Y. et al prepared a series of amphoteric membranes by preirradiation-induced graft copolymerization of styrene and dimethylaminoethyl methacrylate in an aqueous emulsion media followed by solution casting, sulfonation, and protonation.…”