In Situ Neutron Diffraction Study of Lithiation Gradients in Graphite Anodes during Discharge and Relaxation

Abstract

Reduced capacity and rate capability at low temperature operation is a limiting factor for application of lithium-ion batteries in electro mobility. The visualization of electrode inhomogeneity resulting from low-temperature lithium transport limitations can illustrate the shortcomings of current electrode design. To study anode lithiation gradients and relaxation processes, we performed time-resolved in situ neutron diffraction measurements of a commercial high power LiCoO2/Graphite pouch bag battery operated in the temperature range of −20°C to 40°C.