Qing Wang1

1, National University of Singapore, Singapore, , Singapore

In conventional batteries with enclosed configuration, active materials are coated on current collector with binder and carbon additives in order to form conducting electrode sheets. In 2006, “redox targeting” of poorly conductive materials such as LiFePO4 was proposed by us to eliminate the need for carbon additives. In the presence of redox shuttle molecules, an active electrode material can be reversibly delithiated/lithiated via redox targeting reactions without being attached to the current collector, for which the transport of electrons between the material and the current collector is mediated by the diffusion of redox molecules dissolved in the electrolyte. The application of redox targeting reactions to both the anode and cathode intuitively leads to a novel energy storage device — redox targeting-based flow battery. In this novel device, the active materials are stored statically in two separate tanks and power is produced in the cell stack by the redox reactions of redox mediators, disruptively changing the operation mode of the conventional batteries. The transport of electrons between the active materials and the current collector is mediated by the circulation of redox shuttle molecules in the electrolyte. Such flow battery devices present significant advantages over other types of electrochemical energy storage devices in terms of energy density, safety, and operation flexibility for large-scale stationary energy storage. In this talk, the latest progress on the development of various redox targeting-based flow batteries, with the application of redox targeting concept to various battery chemistries, will be reported. The present status, challenges and future development will be addressed in the talk.