Redox flow battery promises safer components, greater capacity

Ars Technica : To accommodate the world’s ever-growing need for energy storage, a team of scientists from three institutes in Jena, Germany, has been working to design a better redox flow battery made of cheaper, less corrosive materials. The researchers used organic polymers as the charge–discharge material, an aqueous sodium chloride solution as the electrolyte, and an inexpensive dialysis membrane to separate the anode and the cathode. Because the membrane must be highly chemically stable to prevent anything other than electrons from passing through it, the researchers tested it by performing some 10 000 charge–discharge cycles. They found that only trace amounts of the polymers slipped through. In addition, the cells managed to retain 80% of their initial capacity. The researchers say their design lays the foundation for a new type of battery that is “safe, metal-free, and all-organic.”