Is it a gimmick? Or a subversion? The chip that claims to be a flow battery

In the battery industry, there is a membrane that is crucial, that is the proton exchange membrane. With the rapid development of hydrogen fuel cells and liquid flow batteries, ion exchange membranes, as the core materials, have also taken advantage of the industry's growth. Just like the chip and the electronics industry, the proton exchange membrane has also tightly "strangled the throat of liquid flow batteries". For a long time, domestic related products have had to rely on imports, and the market has been dominated by American Chemours (DuPont), Gore, etc. The proton exchange membrane is small in quantity and high in price, which can be said to be "priceless". In addition, its unstable import supply, long delivery cycle, and high price have seriously hindered the development of liquid flow batteries.

Proton exchange membrane (ion exchange membrane), as the name implies, is used as a place for proton (hydrogen ion) exchange between positive and negative electrodes. Its special function is to allow protons to selectively permeate, thereby ensuring that the ion exchange between the electrodes is completed smoothly and ultimately completing 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 liquid flow batteries, the proton exchange membrane accounts for about 50% of the cost of the battery stack, and its importance is self-evident.

Breakthrough in the localization of proton exchange membranes

In recent years, domestic companies represented by Dongyue and Kerun have been committed to the localization of ion exchange membranes. They are currently focusing on the production and technical research of perfluorosulfonic acid ion exchange membranes that meet mainstream demand, and have achieved remarkable results.

In 2022, the Dalian Institute of Physical Chemistry, Chinese Academy of Sciences and the Dalian Rongke R&D team researched and developed non-fluorine ion exchange membrane materials, realizing independent small-batch production of non-fluorine membrane materials; in October 2023, Kaifeng Times successfully launched the first batch of non-fluorine ion conductive membranes.

In 2023, Beijing Xingchen announced at an event that they had successfully developed a non-fluorine ion conductive membrane with excellent conductivity and durability in cooperation with Central South University. The electrodes used the company's patented innovative materials to ensure high current density and high energy efficiency of the battery stack. It has been applied in the world's first high-power and high-efficiency all-vanadium liquid flow battery stack - Xingchen 1.

Shanxi Guorun Energy Storage Technology Co., Ltd. is also engaged in the production of high-end ion membranes in liquid flow battery energy storage systems and liquid flow batteries and hydrogen fuel cells. It claims to be the only company in China that has a comprehensive layout of equipment manufacturing and core material production. According to public information, the perfluorinated ion membrane it produces uses advanced membrane-forming integrated technology to achieve the regeneration and recycling of perfluorinated ion membranes.

Recently, Professor Liu Suqin of Central South University said in an interview: China has basically mastered the key materials and technologies of liquid flow batteries. The diaphragm, a key material, was previously imported. In recent years, the products of several domestic companies have achieved good results. my country's liquid flow battery industry is at the forefront of the world, and even leading.

Liquid flow battery, is the membrane-free era coming?

However, the technical route for proton exchange membranes to move from perfluorinated to fluorine-free has not yet been formed, and another voice has been heard in the market that a new membrane-free design may be coming!

Salgenx, Inc.

According to Cailian Press, US technology startup Salgenx has launched a scalable salt water flow battery that can be used in renewable energy, telecommunications towers, oil well pumps, agricultural irrigation pumps, and greenhouse irrigation or lighting. The battery can also be used to store solar or wind energy separately. Gregory Giese, the company's CEO, also said, "It is very suitable for solar energy storage, and has the additional benefit of having heat storage in the salt water electrolyte tank."

The company says the new battery has an energy density of 125.7 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 circulates through electrodes, which regulate the input and output of the battery current. It is reported that the solution can increase its capacity by adding more electrodes and additional electrolyte tanks.

It is worth noting that, unlike most redox flow batteries, this new saltwater flow battery is membrane-free. Salgenx said that the membrane-free design saves huge upfront purchase costs, maintenance and consumables. In addition, Salgenx also said that the brine tank can also be used for heat storage at the same time, combined with a heat pump that uses carbon dioxide as a refrigerant. It is reported that the company is selling licenses to third-party manufacturers to commercialize the solution.

Primus Power Solutions, Inc., USA

Founded in 2009, Primus Power Solutions specializes in providing low-cost, non-degradation and long-life energy storage systems for the commercial, industrial, renewable energy and utility markets. The company's award-winning EnergyPod2 meets the need for long-life batteries to reduce power outages and meet peak power demands, ensuring hours of battery power (20-year life) without degradation.

EnergyPod 2 has excellent energy capacity, with a stable zinc-bromine flow battery (ZBFB), excellent battery architecture and flow architecture, and industry-leading LCOS. In addition, the optimized design of EnergyPod 2 eliminates battery components that limit life, including complex pipes, graphite electrodes and diaphragms/separators. This is a long-lasting (zinc-bromine) non-fading flow energy storage battery without a diaphragm.

It is reported that Primus Power Solutions invested in the research and development of long-lasting liquid flow energy storage battery technology in 2009. After obtaining US$1.36 billion in financing in 2017, it entered the second-generation research and development and pilot test, and achieved success in 2018. In 2019, it jointly developed the third-generation product with Columbia University.

CFE 2024 China Liquid Flow Battery Energy Storage Conference and Exhibition, created by the Asian Liquid Flow Battery Industry Alliance, Global Liquid Flow Battery Network, China New Energy Network (Energy Pass), and Global Energy Storage Network, will be held in Hangzhou from April 25 to 26. It is the first comprehensive platform in China that takes liquid flow batteries as the absolute protagonist and brings together enterprises from the entire industry chain and industry elites from the top circles of industry, academia, and research. We will strive to build an online and offline business and network business circle to help friends who are interested in energy, electricity, energy storage, power grids, industry and commerce, venture capital institutions, investors, etc. to have a personal, fast and all-round understanding of this industry. I hope that here we can discuss technology, interpret policies, formulate industry standards, analyze the market, explore business models, business cooperation, friendly exchanges, answer questions, and work together to promote the scale, industrialization and commercial development of the liquid storage industry! Looking forward to your participation!

——Liquid flow battery, born for energy storage!

China New Energy Network/Global Flow Battery Network Zhou Zhou

(Please indicate the source when reprinting, thank you!)

Appendix: Top 10 Flow Battery Companies in the World

1. CellCube (Enerox GmbH)

Founded: 1986

Location: Wiener Neudorf, Austria

The Austrian company Enerox GmbH, manufacturer of all-vanadium flow batteries under the brand name “CellCube”, is one of the leading companies in long-term energy storage solutions.

CellCube provides high-quality, cost-effective, grid-connected and off-grid redox flow battery solutions to meet the global demand for energy storage infrastructure. CellCube has a reputation for realizing the largest number of flow battery projects in the industry. Against the backdrop of rapidly growing demand for long-duration energy storage solutions, South African vanadium company Bushveld Minerals has invested in Enerox to expand sales and manufacturing capabilities.

CellCube is one of the leading choices for multi-hour energy storage systems. In years of rigorous durability testing, key components of the CellCube system have undergone more than 10,000 cycles without interruption - demonstrating robust performance even in the most demanding environments.

ESS Tech Inc.

Founded: 2011

Location: Wilsonville, Oregon, USA

Founded in 2011, ESS designs, manufactures and deploys long-life and low-cost iron flow batteries for commercial and utility-scale energy storage applications. In 2019, ESS Inc. raised a significant $30 million Series C round of financing from investment group Breakthrough Energy Ventures (BEV) and SoftBank Group’s SB Energy.

The company's Energy Warehouse and Energy Centre use abundant iron, salt and water as electrolytes, with minimal impact on the environment.

3. Invinity Energy Systems

Founded: 2009

Location: St. Helier, Jersey

North American Avalon Battery and British company redT energy have merged to form "Invinity Energy Systems" - a leading global vanadium flow battery company specializing in utility-scale energy storage for commercial and industrial (C&I), grid-scale and microgrid applications. Vanadium flow batteries are designed to be non-flammable and safe, providing long-term flexibility and reliability.