Ion exchange membranes for flow batteries

Abstract

The invention discloses an ion exchange membrane for a flow battery. The ion exchange membrane comprises an organic porous membrane and a perfluorosulfonic acid ion exchange resin, wherein the organic porous membrane is used as a matrix and the perfluorosulfonic acid ion exchange resin is infiltrated into holes of the organic porous membrane. According to the invention, prepared from the perfluorosulfonic acid ion exchange resin with good chemical stability and the organic porous membrane, the ion exchange membrane for the flow battery has good chemical stability and good compactness, electrical performance and vanadium blocking performance; the cost of the ion exchange membrane is far lower than that of a perfluorosulfonic acid ion exchange membrane with same thickness. The invention further discloses a preparation method for the ion exchange membrane for the flow battery. The preparation method is simple and reliable, has low requirements on equipment, can easily realize large-batch production and conveniently realize large scale commercialization of a vanadium battery and promotes development of new energies like wind energy and luminous energy.

Description

technical field [0001] The invention belongs to the technical field of functional polymer membrane materials, and in particular relates to an ion exchange membrane for a liquid flow battery and a preparation method thereof. Background technique [0002] With the rapid development of the economy, people's living standards are getting higher and higher, and the demand for energy is also increasing. However, in recent years, large-scale and long-lasting smog weather has seriously affected people. Therefore, the development of new clean energy has become a current strategic issue. At present, important breakthroughs have been made in the large-scale development and utilization of renewable energy in China, such as wind energy, solar energy, ocean energy, etc., but these new energy sources are greatly affected by factors such as weather and environment, and continuous and stable output cannot be guaranteed during the power generation process. The development and utilization of e...

AI Technical Summary

Problems solved by technology

This type of ion exchange membrane has the advantages of low cost, high membrane tensile strength, and good vanadium resistance, but its electrical properties are greatly affected by the degree of sulfonation. The most important defect is that the chemical stability of this type of ion exchange membrane is poor. The long-term performance of the membranes has been questioned, and so far this type of ion-exchange membranes has not been successfully used commercially in vanadium batteries

[0006] In addition, it has been publicly reported that the organic porous separation membrane is used as the main material of the vanadium battery diaphragm, and at the same time, a layer of functional polymer film material containing charge groups is compounded on the surface of the porous separation membrane to improve the ion selective permeation of the porous separation membrane. The composite film prepared by this method has high chemical stability and low cost. It can be used in vanadium batteries in theory, but the uniformity of the composite film is poor. At the same time, the thin and dense film is prone to perforation during preparation and use. phenomenon, so this type of diaphragm has technical risks in the commercial application of vanadium batteries