Simultaneous neutron and X-ray tomography for visualization of graphite electrode degradation in fast-charged lithium-ion batteries

Abstract

Advanced battery characterization using neutron and X-ray-based imaging modalities is crucial to reveal fundamental degradation modes of lithium-ion batteries (LIBs). Taking advantage of the sensitivity of neutrons to some low-Z (Li) and X-rays to high-Z materials (Cu), here we demonstrate the viability of simultaneous neutron- and X-ray-based tomography (NeXT) as a non-destructive imaging platform for ex situ 3D visualization of graphite electrode degradation following extreme fast charging (XFC). In addition, we underscore the benefits of the simultaneous nature of NeXT by combining the neutron and X-ray data from the same sample location for material identification and segmentation of one pristine and two XFC-cycled graphite electrodes (9C charge for 450 cycles). Our ex situ results and methodology development pave the way for the design of NeXT-friendly LIB geometries that will allow operando and/or in situ three-dimensional (3D) visualization of electrode degradation during XFC. • Simultaneous neutron and X-ray tomography (NeXT) is a non-invasive imaging method • NeXT enables visualization of graphite electrode degradation after fast charging • NeXT overlaps neutron and X-ray data from same sample area to identify materials • NeXT shows qualitative correlation between electrode degradation and plated Li Advanced battery characterization is critical to reveal fundamental degradation modes of lithium-ion batteries. Using the sensitivity of neutrons to lithium and X-rays to copper, Yusuf et al. demonstrate the viability of simultaneous neutron and X-ray tomography as a non-invasive imaging modality for visualization of graphite electrode degradation following fast charging.