Recent Advances and Optimization Strategies on the Electrolytes for Hard Carbon and P‐Based Sodium‐Ion Batteries

Hard carbons (HCs) and P‐based materials (including red phosphorus, black phosphorus, and metal phosphides) represent the most promising anodes for the commercialization of sodium ion batteries. The electrochemical performance of SIBs is determined not only by the structure of electrode materials, but it is also highly dependent on the matched electrolyte. In this review, the optimization, the matching strategies and the advanced characterization techniques of the electrolytes system for HCs and P‐based anodes are discussed based on the recent advance. The effective optimization strategies are summarized from three aspects: sodium salts, solvents, and additives. The challenges and perspectives are also discussed in this review.