Fluorophosphates and fluorosulfates cathode materials: Progress towards high energy density sodium-ion battery

The rapid diffusion of renewable energy boosts the wide deployment of large-scale energy storage system. With the low cost and high crustal abundance, sodium-ion battery (SIB) technology is expected to become a dominant technology in that area in the future. Toward the practical application, novel cathode materials are urged to develop that show high energy density without sacrificing their cost and benignity to the environment. While the years of many studies, this still remains a huge challenge to battery scientists. In this review, we discuss recent breakthroughs in SIB cathode materials with high energy density, namely fluorphosphates and fluorosulfates. The design of materials, the crystal structure, the electrochemical performance, and the underlaying intercalation mechanism are systematically reviewed. Useful strategies and research directions are also provided to advance future high-energy, low-cost, and ecofriendly cathode materials for next generation SIB.

Automated summary

The rapid diffusion of renewable energy promotes the widespread adoption of large-scale energy storage systems. The sodium-ion battery (SIB) technology, with its low cost and abundant resources, is expected to dominate the field in the future. However, the development of novel cathode materials that exhibit high energy density, low cost, and environmental friendliness remains a major challenge for battery scientists. This review discusses recent advancements in SIB cathode materials, specifically fluorphosphates and fluorosulfates, focusing on material design, crystal structure, electrochemical performance, and intercalation mechanism. The review also provides valuable strategies and research directions for the future development of high-energy, low-cost, and eco-friendly cathode materials for next-generation SIB.