Sodium-ion batteries are an emerging battery technology, on the cusp of commercialization, with promising cost, safety, sustainability, and performance benefits when compared to lithium-ion batteries. They can use widely available and inexpensive raw materials and existing lithium-ion production methods, promising rapid scalability. SIBs are an attractive prospect in meeting global demand for carbon-neutral energy storage, where lifetime operational cost, not weight or volume, is the overriding factor. Increasingly sodium-ion batteries have characteristics comparable to lithium iron phosphate (LFP) batteries, suggesting that even automotive applications are possible.
SIBs have the same fundamental working principle as LIBs but rely on sodium rather than lithium as mobile cations. Unlike lithium, sodium does not electrochemically alloy with aluminum at room temperature. Thus, the copper current collector on the anode can be replaced by cheaper aluminum; it not only lowers the SIB costs, but also reduces the transportation risks, as SIBs can be transported completely discharged at 0V. Hard carbon is typically used as the anode active material instead of graphite, as crystalline graphite has poor storage capabilities for sodium ions. Various cathode chemistries based on layered transition metal oxides, polyanionic compounds, and Prussian Blue Analogues can be used. Electrolytes and separators, as well as the positive current collectors, are similar to LIBs, except for the use of sodium salts in the electrolyte.
Abundances of the elements (data page) -- that is correct for the Earth's crust.
