On May 6th, Science published The Comment Paper on Li-O2 battery of Shen Yue, assoiciate professor of Power and Energy Storage Battery Lab of School of Material Science & Engineering, HUST.
Known as the future battery, Li-O2 battery is a chargeable battery based on the energry release and strorage of cyclable chemical reaction of Lithum and oxygen with a theoretical per capita energy ten times that of Lithum ion battery. But the development of this battery faces many challenges, one of which is the unsatisfactory reversibility of cathode electrochemical reaction. On Oct. 30th, Prof. Clare P. Grey published a paper in Science, in which he put forward a totally different cathode electrochemical reaction mechniam and thought that their cathode was able to cycle 2000 times at a limited capacity of 1000 mAh g−1. This achievement aroused international applaud, thus reputed as the “breakthrough” of Li-O2 battery and the top ten progress in science & technology by Reuters.
Associate Prof. Shen Yue’s research team found that the mechanism put forward in this paper is evidently fallacious in electric potential. Through systematic research and analysis on the themodynamic equilibrium potential, the reaction acitivity of Lil3 and LiOH, Oxygen evolution rate, the accumulation phenomenon of Lil3 and elctrolyte side reaction capacity, the team boldly argued that the mechanism put forward by Prof.Grey was no sense. The experiemtal phenomenon Grey has noticed is caused by some side reactions of catalyst. This result gained the support and perfection of Shu-Lei Chou and Shi-Xue Dou from University of Wollongong, Australia, and they co-composed this comment paper, of which Shen Yue is the leading author and corresponding author. They argue that Li-O2 battery based on the formation and decomposition of LiOH is fallacious and puts forward their explanation. After posting the paper to Science, they won the commendatory remarks of the paper examiner such as “excellent comment”“strong experimental evidence”. This comment paper aroused wide attention in the academic circle after its publishment with a total download volume of 1000 times within the first three days. Science also reported the themodynamic therectical analysis of V. Viswanathan, from Carnegie Mellon University in the formation and decomposition of LiOH, the main conclusion of which conforms to the comment paper of Associate Prof. Shen Yue.
Shen Yue thinks that Li-O2 Battery is a battery system worth research. However the side reaction is complicated. In the traditional half battery limited capacity cycling tests, many side reactions have been hiden. Currently the limited-capacity cycling test is misleading when the electrolyte contributes considerable parasitic reaction capacity. So our current research is mainly based on a more objective mechanism analysis. We will cope with the molecular stability, introduce new catalysts, fundamentally improve the cycling stability of Li-O2 battery and ultimately lay a solid foundation for its application.
Link of the comment paper：http://science.sciencemag.org/content/352/6286/667.1.full