Newly developed compound could allow sustainable, cost-effective, large-scale power storage

To produce an economical redox circulate battery, researchers primarily based on the South China University of Technology have synthesized a molecular compound that serves as a low-cost electrolyte, enabling a steady circulate battery that retains 99.98% capability per cycle. They printed their method on August 14 within the Energy Material Advances.

Comprising two tanks of opposing liquid electrolytes, the battery pumps the constructive and destructive liquids alongside a membrane separator sandwiched between electrodes, facilitating ion exchanges to provide power. Significant work has been devoted to growing the destructive electrolyte liquid, whereas the constructive electrolyte liquid has obtained much less consideration, in line with corresponding writer Zhenxing Liang, professor within the Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology.

“Aqueous redox flow batteries can realize the stable electrical output for using unsteady solar and wind energy, and they have been recognized as a promising large-scale energy storage technology,” Liang stated. “Electroactive organic merit of element abundance, low cost and flexible molecular control over the electrochemical features for both positive and negative electrolytes are regarded as key to developing next-generation redox flow batteries.”

Liang and his workforce targeted on TEMPO, a chemical compound with simply reversed oxidation states and excessive potential for power, a desired high quality in constructive electrolytes.

“However, TEMPO cannot be directly applied to aqueous redox flow batteries due to the high hydrophobicity of the molecular skeleton,” Liang stated, explaining that TEMPO, left unmodified, is not going to dissolve within the liquid wanted to facilitate the power alternate within the circulate batteries. “We developed a strategy to functionalize TEMPO with viologen, an organic compound that has highly reversible redox reactions, to improve TEMPO’s hydrophilicity.”

According to Liang, viologen is very soluble in water, which will increase TEMPO’s skill to dissolve in water. Viologen additionally chemically withdraws electrons from atomic companions, which elevates its potential to alter its oxidative state. Viologen can also be a salt, which endows TEMPO with what Liang calls “a decent conductivity” in an aqueous answer.

When the synthesized viologen-modified TEMPO was examined in a circulate battery, the researchers discovered that the battery retained capability of 99.98% per cycle, which means the battery might maintain almost all its saved power when not in energetic use.

“This work overcomes the disadvantages of TEMPO by viologen-functionalization and realizes its application in aqueous redox flow battery,” Liang stated. “The molecular design concept provides a strategy for novel organic electroactive materials and lays a foundation for the application of aqueous organic circulate battery.”

Other contributors embrace Shuzhi Hu, Liwen Wang, Xianzhi Yuan, Zhipeng Xiang, Mingbao Huange, Peng Luo, Yufeng Liu and Zhiyong Fu, all with the Key Laboratory of Fuel Cell Technology of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology. Hu can also be affiliated with the School of Materials Science and Engineering, Sun Yat-sen University.

Provided by
Beijing Institute of Technology Press Co., Ltd