In the battery industry, there is a membrane is very important, that is, proton exchange membrane, in the development trend of hydrogen fuel cells and flow batteries in full swing, ion exchange membrane, as the core material, has also hitched a ride on the growth of the industry. For a long time, domestic related products have to rely on imports, and the market has been dominated by Chemours (DuPont), Gore, etc., the amount of proton exchange film is small and the price is high, which can be described as "difficult to buy", and its import is unstable, the delivery cycle is long, and the problems of high quality have seriously hindered the development of flow batteries.
Proton exchange membrane (ion exchange membrane), as the name suggests, is used as a place for proton (hydrogen ion) exchange between positive and negative electrodes, and its specific function is to allow protons to be selectively transmitted, so as to ensure the smooth completion of ion exchange between electrodes, and finally complete the function of the battery. At the same time, the proton exchange membrane also isolates the electrolyte of the positive and negative electrodes to avoid cross-contamination. As one of the key materials of flow batteries, proton exchange membranes account for about 50% of the cost of battery stacks, and its importance is self-evident.
In recent years, domestic enterprises represented by Dongyue and Kerun have been committed to the localization of ion exchange membranes, and are currently mainly focusing on the production and technical research of perfluorosulfonic acid ion exchange membranes in mainstream demand, and have achieved remarkable results.
In 2022, the Dalian Institute of Physics and Chemistry of the Chinese Academy of Sciences and the R&D team of Dalian Rongke Research and Development Research and Development Research and Development Research and Development (DRI) researched and developed non-fluorinated ion exchange membrane materials, realizing the independent small-batch production of non-fluorinated membrane materials. In October 2023, Kaifeng Times successfully rolled off the first batch of non-fluorinated ion conductive membranes.
In 2023, Beijing Xingchen announced at an event that they have successfully developed a non-fluoride ion conductive membrane with Central South University with excellent conductivity and durability, and the electrode uses the company's patented innovative materials to ensure high current density and high energy efficiency of the stack. And it has been applied in the world's first high-power and high-efficiency all-vanadium liquid flow stack - Xingchen No. 1.
Shanxi Guorun Energy Storage Technology Co., Ltd. is also engaged in the production of high-end ion membranes in flow battery energy storage systems and flow batteries and hydrogen fuel cells, and claims to be the only enterprise in China that comprehensively lays out equipment manufacturing and core material production. According to public information, the perfluorinated ion membrane produced by it adopts advanced film-forming integration technology to realize the regeneration and recycling of perfluorinated ion membrane.
A few days ago, Professor Liu Suqin of Central South University said in an interview: the key materials and technologies of flow batteries can be basically mastered in China, and the separators in the key materials have previously relied on imports, and the product results of several domestic companies have been good in recent years. China's flow battery industry is at the forefront of the world, or even relatively leading.
However, the technical route of proton exchange membrane from perfluorinated to fluorine-free has not yet been formed, and there is another voice in the market, and a new membrane-free design may be coming!
Salgenx, USA
According to the Associated Press, American technology startup Salgenx has launched a scalable brine flow battery that can be used in renewable energy, telecommunications towers, oil well pumps, agricultural irrigation pumps, and greenhouse irrigation or lighting. The battery is also suitable for storing solar or wind energy separately. The company's CEO, Gregory Giese, also said, "It's great for solar energy storage, with the added benefit of having heat storage in a brine electrolyte tank." ”
The company says the new battery has an energy density of 1257 wh/l。It requires two large tanks filled with liquid electrolytes, one of which is salt water and the other is a proprietary electrolyte. The liquid is circulated through the electrodes, which regulate the input and output of the battery current. It is reported that the solution can increase the capacity by adding more electrodes and additional electrolyte tanks.
It's worth noting that, unlike most redox flow batteries, this brand new brine flow battery is film-free. Salgenx says the membrane-free design saves significant upfront procurement costs, maintenance and consumables. In addition, Salgenx said that the brine tank can also be used for heat storage, in combination with a heat pump that uses carbon dioxide as a refrigerant. It is reported that the company is in the process of licensing to third-party manufacturers** to commercialize the solution.
Primus Power Solutions, Inc., USAcompany
Founded in 2009, Primus Power Solutions specializes in providing low-cost, attenuation-free, and long-life energy storage systems for the commercial, industrial, renewable, and utility markets. The company's award-winning EnergyPod2 meets the need for a long-lasting battery to reduce outages and meet peak power demand, ensuring hours of battery power (20-year life) without degradation.
EnergyPod 2 has excellent energy capacity, with a stable zinc-bromine flow battery (ZBFB), superior battery architecture and flow architecture, and industry-leading LCOS. In addition, the optimized design of the EnergyPod 2 eliminates life-limiting battery components, including complex tubing, graphite electrodes, and separator separators, making it a long-lasting (zinc-bromide) attenuation-free flow energy storage battery without a separator.
It is reported that Primus Power Solutions invested in the research and development of long-lasting flow energy storage battery technology in 2009. In 2017, it won 1After $36 financing, it entered the second generation of R&D and pilot test, and was successful in 2018. In 2019, the third-generation product was jointly developed with Columbia University.
**: China New Energy Network