Bulk Alloy Anodes for Sodium‐Ion Batteries

Abstract Sodium‐ion batteries (SIBs) are considered a promising candidate for next‐generation energy storage systems due to the abundance of available sodium resources. The practical application of SIBs critically depends on developing durable electrode materials with high capacity and long lifespan, particularly when it comes to finding suitable anode materials. Alloy‐type anodes are appealing for their high capacities owing to the multiple electron transfer alloying reaction mechanism, making them ideal for high‐energy‐density SIBs. However, the huge volume change during charge/discharge process can cause the active material pulverization to detach from the current collector, leading to poor cycling performance, especially for bulk alloy anodes. Despite this challenge, recent progress in bulk or micro‐sized alloy anodes for SIBs have shown promise. This review highlights the up‐to‐date advancements and research on bulk alloy‐based anode materials for SIBs, including synthetic strategies and electrochemical performance. The crucial role of bulk alloy anodes in advancing SIB technology is discussed, along with a summary of research on bulk alloy‐type anodes and their compounds for sodium storage. Strategies to improve the electrochemical performance of bulk alloy‐based anode materials are also explored. Additionally, the potential of multi‐component alloys and high‐entropy alloys as future research directions for alloy‐based anodes is proposed.