学科进展系列报告

报告题目：Redox flow batteries for charging both electric & hydrogen cars

Redox flow batteries store energy directly in electrolyte solutions rather than in the electrode bodies as in classical secondary batteries, Hence, the energy stored depends on the size of the electrolyte holding tanks, whilst the power delivered depends on the size of the electrode area.

Different redox flow batteries are commercially available and their power can exceed the Megawatt. The state-of-the art of redox flow batteries shall first briefly be reviewed. From a physical chemistry viewpoint, we shall discuss the concept of redox electrocatalysis or how to carry out electrochemical reactions on electrically floating particles. As an example, we shall present our work on solid booster for redox flow batteries, where a redox intercalation material is added to the tank of the electrolyte to boost the energy storage. Then, we shall present our work using a vanadium redox flow battery (200kW/400kWh) that is used to store electricity from the main. This battery is then used to recharge electric cars. To this end, we have developed a fast charger using a 400 V DC line with the goal of charging an electric car in less than 30 minutes. The DC-DC coupling between the battery and the fast charger will be discussed. This redox flow battery is also used to feed a 50 kW alkaline electrolyser producing about 1 kg of hydrogen per hour for refuelling fuel cell cars. This electrolyser is designed to operate intermittently to produce hydrogen on demand to avoid the storage of large amount of hydrogen. This demonstration fueling station for electric cars clearly show the advantages of redox flow batteries. Indeed, the battery can meet irregular high-power discharging peaks when cars come to the station, and can recharge when the grid has spare capacity. For more information, please visit: www.electromobilis.ch. Finally, we shall discuss the oxidation of Vanadium(II) in sulfuric acid solutions on Mo2C particles  using redox electrocatalysis. This reaction can be used to produce hydrogen on demand and at high pressures using directly a Vanadium redox flow battery. We shall present results form a smaller pilot-plant operating on this principle using a 10kW/40kWh Vanadium redox flow battery and producing a kilo of hydrogen a day.

报告人：Prof. Hubert Girault

Institute of Chemical Sciences and Engineering

Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland

Hubert Girault is the author of 2 textbooks, the co-author of about 500 scientific publications with more than 15'000 citations and the co-inventor of more than 15 patents. During his academic career, he has supervised more than 60 PhD students. 25 alumni of his laboratory are now Professors. He has received Faraday medal 2006, Royal Society of Chemistry, and Reilley Award 2015. He is the Fellow of the International Society of Electrochemistry, and the Fellow of Royal Society of Chemistry.

报告时间：2019年03月18日，周一，10:00

报告地点：江湾化学楼A3030

邀请人：乔亮  研究员