MEMBER

In order to determine the rate-determining reactions achieve higher performance in electrochemical devices such as lithium ion batteries and fuel cells, it is important to understand reaction hierarchies over wide temporal and spatial ranges (from the nanometer to the centimeter scale) that proceed sequentially within the device. Research and development of new advanced analysis technologies to enable operando observation during electrochemical reactions is necessary to understand the structure of these hierarchies. In this study, we established an operando measurement technique that enables analysis of the electrode/electrolyte interface of the reaction site, phase transitions of active materials, and macro reactions within real electrodes over various spatial and temporal scales.  We also provided fundamental knowledge of the dynamic behavior of the lithium ion battery. This analytical technique is a dramatic step forward in that it pioneers a new way of performing kinetic analysis by introducing space and time axes for reaction analyses. It is also applicable to reaction analysis of various types of electrochemical devices. Moreover, we successfully designed and developed materials for innovative batteries by integrating information obtained using this technique.