(Digital Presentation) New Advances and 24/7 Accessibility in Battery Research- Bringing Synchrotron X-Ray Techniques to Your Lab
Authors: Lau S.H. , Seshadri Srivatsan , Vine David , Zan Guibin , Stripe Benjamin , Su Frances , Gelb Jeff , Qiao Ruimin , Gul Sheraz , Matusik Katie , Lewis Sylvia , Yun Wenbing 
Published: July 2022

Rechargeable battery research often involves improving electrodes to electrolyte materials with new chemistry with the end goals to lower cost, extend cycle life, higher energy densities and better safety. Advancements in battery and fuel cell research require the understanding of the complex interplay of several components and factors in a battery ecosystem. It calls for an integrated and multimodality approach involving several new analytical techniques which have to be capable of probing the batteries electrochemistry, structures and composition at different length and time scales, several of which have to be performed non destructively (ex-situ, in situ and in operando). Because of the need to study these in operando or at higher resolution or sensitivity, conventional lab based x-ray techniques are often inadequate. Most of this research is currently performed through synchrotron X-ray techniques. These include: X-ray Absorption Spectroscopy (XAS) to probe changes in oxidation states, bond lengths and coordination numbers of electrochemistry during charge-discharge cycles. XAS comprise XANES (X-ray absorption near edge spectroscopy) & EXAFS (Extended X-ray Absorption Fine Structure). They provide information on element-specific changes in oxidation state and local atomic structure. Such microscopic descriptors are crucial for elucidating charge transfer and structural changes associated with bonding or site mixing, two key factors in evaluating state of charge and modes of cell failure or catalytic efficiency. Another major technique is synchrotron X-ray Imaging at multiple lengthscales, from micrometers to 10s of nanometers through 3D X-ray Microscopy (XRM) to determine structural changes and degradation over time of the complex system, from the electrodes, separators, current collectors to binders. Trace level elemental composition at the ppm or sub-ppm level can be studied through high sensitivity synchrotron X-ray fluorescence spectroscopy (s-XRF)- to track the migration of metallic ions from cathode to anode during charge-discharge cycle or to investigate cross contamination during manufacturing.

Unfortunately, many of these X-ray techniques such as XAS has to be performed almost exclusively at synchrotron X-ray light sources, where beamtime is infrequent and experiment time-frames are limited. As a consequence, high level battery, fuel cell or catalyst research in many research institutions have been largely curtailed. In this talk, we will discuss the advancements made in high flux, tunable lab x-ray sources and high efficiency optics for enabling novel synchrotron-equivalent XAS, XRM and XRF techniques in the laboratory. Breakthrough correlative applications through these suite of tools in the field of battery research and catalysts are now feasible in your own laboratory 24/7, without the constraint of limited access nor the research continuity challenges at synchrotron beamlines. Measurements results (including in operando) will be illustrated for conventional NMC batteries to novel solid-state lithium air batteries and next generation battery materials.