Congratulations to Keith Gordon and collaborators from Shanghai on their recent paper in Nano Today. The paper entitled “Functional separator materials of sodium-ion batteries: Grand challenges and industry perspectives.” (Nano Today 2024, 55, 102175. DOI: https://doi.org/10.1016/j.nantod.2024.102175) describes the issues around battery membranes and area that spatially offset Raman spectroscopy may be able to play a role in understanding.