Liquefied gas electrolytes for electrochemical energy storage devices

Electrochemical capacitors and lithium-ion batteries have seen little change in their electrolyte chemistry since their commercialization, which has limited improvements in device performance. Combining superior physical and chemical properties and a high dielectric-fluidity factor, the use of electrolytes based on solvent systems that exclusively use components that are typically gaseous under standard conditions show a wide potential window of stability and excellent performance over an extended temperature range. Electrochemical capacitors using difluoromethane show outstanding performance from –78° to +65°C, with an increased operation voltage. The use of fluoromethane shows a high coulombic efficiency of ~97% for cycling lithium metal anodes, together with good cyclability of a 4-volt lithium cobalt oxide cathode and operation as low as –60°C, with excellent capacity retention.

Source: ScienceNOW - June 29, 2017 Category: Science Authors: Rustomji, C. S., Yang, Y., Kim, T. K., Mac, J., Kim, Y. J., Caldwell, E., Chung, H., Meng, Y. S. Tags: Chemistry, Online Only r-articles Source Type: news