Recent advances in high energy-density cathode materials for sodium-ion batteries

Large-scale energy storage technologies are in great demands for the enhanced power grid efficiency and wide renewable energy source applications. Various electrochemical energy storage devices, including lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) et al. with long operating life and high energy conversion efficiency, have achieved rapid growth in the past 30 years, which make them the best choice for the large energy storage applications. Recently, SIBs have been proposed as the most promising solution for the large-scale energy storage systems because of the huge abundant and low cost of sodium resources. High energy-density cathode materials are now the main limits for high performance SIBs. Herein, the advances made in high energy-density cathodes for SIBs, together with the sodium storage mechanism; the remaining challenges and perspectives for high energy-density cathode materials, are discussed thoroughly based on recent researches and publications. Meanwhile, the achievement of material simulations in the design and development of cathode materials for SIBs, especially the high-throughput strategy and data science, is also introduced. This review is expected to accelerate the progress on SIB studies for high energy-density cathode materials, and more importantly, open up new opportunities for the high-energy cathode materials design in sodium storage.