Katerina Aifantis

Abstract:

Na-ion batteries are the most promising energy sources for stationary applications. Numerous electrode materials that are used in Li-ion cells seem promising for use in Na-ion cells as well. A stable long term capacity, however, is yet to be achieved by these electrode materials. The present talk will compare the differences between the sodiation and lithiation mechanisms of TiS₂ which can serve as a cathode material. X-ray diffraction and electron microscopy illustrate that cycling with respect to lithium results in long term electrochemical stability, whereas with respect to sodium, irreversible phases and cracks form, giving rise to a capacity decay. The experimental results are supported with continuum mechanics studies on stress evolution during cycling.