XPS is routinely used to study the surface composition of Li battery electrodes as a function of use, which is critical to understanding mechanisms that may limit the lifetime of a battery. Due to the reactivity of Li battery electrode surfaces it is important to have the ability to transport samples from a controlled environment, such as a glove box, to the surface analysis instrument under vacuum or with an inert cover gas. Shown below are spectra from a lithium anode surface with and without air exposure. The observed surface chemistries show how important it is to protect a lithium anode surface from air exposure.
If a Li anode surface is exposed to air it typically forms carbonates that do not reflect the actual surface chemistry. Without air exposure Li metal, Li oxides and Li hydroxides are visible in XPS spectra from the anode's surface.
