Room-temperature stationary sodium-ion batteries have attracted great attention particularly in largescale electric energy storage applications for renewable energy and smart grid because of the huge abundant sodium resources and low cost. In this article, a variety of electrode materials including cathodes and anodes as well as electrolytes for room-temperature stationary sodium-ion batteries are briefly reviewed. We compare the difference in storage behavior between Na and Li in their

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... s electrodes and summarize the sodium storage mechanisms in the available electrode materials. This review also includes some new results from our group and our thoughts on developing new materials. Some perspectives and directions on designing better materials for practical applications are pointed out based on knowledge from the literature and our experience. Through this extensive literature review, the search for suitable electrode and electrolyte materials for stationary sodium-ion batteries is still challenging. However, after intensive research efforts, we believe that low-cost, long-life and roomtemperature sodium-ion batteries would be promising for applications in large-scale energy storage system in the near future. Broader context With the rapid development of renewable energy sources, such as the wind and the sun, large-scale electric energy storage systems are becoming extremely important to realize the smooth integration of these intermittent energies into the grid. Among the potential energy storage technologies, electrochemical secondary battery technology is one of the most promising means of storing electricity on a large-scale because of exibility, high energy conversion efficiency and simple maintenance. So far, lithium-ion batteries are the most successfully developed technology, have been widely used in portable electronic devices and have been regarded as the best choice for (hybrid) electric vehicles. The latter application raises concern for a possible shortage of the limited lithium resources in the Earth's crust. Therefore, alternatively, room-temperature sodium-ion batteries have again aroused a great deal of interest recently, particularly for largescale stationary energy storage applications, due to the practically innite sodium resources and their low cost. This review is intended to provide a wider literature overview and present our perspective on designing better materials for stationary sodium-ion batteries to realize practical applications in the near future.