Prof. Dr. Jianbing Jiang
Unviersity of Cincinnati
Prof. Dr. Jianbing Jiang
About the Speaker
Jianbing “Jimmy” Jiang is an Assistant Professor in the Department of Chemistry at the University of Cincinnati since August 2018. He earned his Bachelor’s degree from Jiangnan University, China in 2007. He attained his Master’s degree from East China University of Science and Technology in 2010, where he worked with Prof. He Tian on the design and synthesis of a series of polymeric chemosensors for the detection of environmentally hazardous ions (e.g. Hg2+). Then he moved to the US in 2010 to peruse his Ph.D. degree at North Carolina State University (Ph.D. advisor: Jonathan S. Lindsey), and his research was concentrated on the development of synthetic methodologies for the preparation of various property-tunable photosensitizers and incorporation of these chromophores into self-assembled materials for light-harvesting and energy-transfer studies. In 2015, he joined Yale University as a Postdoctoral Associate in the Department of Chemistry and Yale Energy Sciences Institute, working with Professors Gary W. Brudvig and Robert H. Crabtree, where he designed, synthesized and characterized novel inorganic catalysts and organometallic materials for small molecule activation, specifically for water oxidation and proton reduction to value-added products. He was promoted to an Associate Research Scientist in 2017.
Abstract
High-voltage membrane-free redox flow batteries
While membrane-free batteries have been successfully demonstrated in static applications, membrane-free batteries in authentic flow modes with high energy capacity and high cycle life are rarely reported. To expand the electrochemical window of the biphasic electrolyte, the aqueous phase has been replaced with a non-aqueous phase to construct non-aqueous/non-aqueous biphasic and triphasic electrolytes. In the biphasic approach, an immiscible non-aqueous electrolyte setup is formed with two distinct electrolyte phases: 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (BMP-TFSI) with LiTFSI as the anolyte and fluoroethylene carbonate (FEC) with LiTFSI as the cathode. This configuration allows for phase separation. Biphasic cells show promising results for high-voltage stability and moderate energy densities, but encounter capacity retention issues during extended cycles due to interfacial limitations. In contrast, the triphasic system incorporates a third electrolyte layer (NFTTS) between the anolyte and cathode phases, which significantly improves performance by acting as an ion-selective barrier. The triphasic electrolyte layer overcomes some of the limitations of biphasic devices by preventing self-discharge and reducing inter-surface instability. This layer is particularly advantageous under dynamic (flow) conditions, as it improves coulombic efficiency and capacity conservation, with nearly 100% efficiency observed under static and flow conditions. This triphasic setup demonstrated high compatibility with lithium-metal anodes and achieved high coulombic and energy efficiency over extensive cycling, demonstrating the enhanced potential of membrane-free triphasic RFBs in biphasic configurations.