Readiness Level of Sodium-Ion Battery Technology: A Materials Review

Since the breakthrough achieved in the research around material intercalating lithium, almost a decade has passed before the commercialization of the first lithium-ion battery (LIB). On the brink of an energy voracious future, convergence of scientific efforts over efficient and low-cost energy production and storage would be advantageous and beneficial. The research hovering around sodium-ion rechargeable batteries (SIBs), a more sustainable alternative to LIBs, has been observing a positive momentum for ten years now, and chemically stable and electrochemically performing anode and cathode materials represent important milestones on the path toward a commercial full-cell. Material science breakthroughs achieved in carbon and graphite based matrices, layered and open framework structures, and sodium storing alloys, disclose new full-cell set up opportunities going beyond traditional "rocking chair" configuration. In this contribution an in-depth analysis of chemical and physical principles lying beyond the energy storage provided by SIBs most recently investigated active materials is given. In the second half of the review, challenges, opportunities, and state-of-the art description of full-cell SIBs lab scale prototypes are discussed. The latter, indeed, stands for a technological validation of a low-cost alternative to lithium-ion batteries guaranteeing energy densities close to 150 Wh kg(-1).