Challenges and Opportunities in Electrical Energy Storage 

This presentation will deal with challenges and opportunities in electrical energy storage technologies with emphasis on batteries, supercapacitors and redox flow batteries. We will focus on some of our recent work including the development of operando methods with emphasis on X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), X-ray microscopy and tomography and transmission electron microscopy (TEM) under active potential control. The utility of these methods will be illustrated by selected examples including organic materials, Li/S batteries and lithium dendrite formation dynamics. The use of operando TEM will be illustrated by exploring the lithiation/de-lithiation dynamics of LiFePO₄ via energy-filtered TEM. Finally the concept of symmetrical redox flow batteries will be introduced and demonstrated. The presentation will conclude with an assessment of future directions.