Design and synthesis of advanced electrode materials: from Li-ion to Na-ion batteries

The rising demand for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) as power sources has increased the need for advanced electrode materials that offer improved electrochemical performance and structural durability. While research at the cell and pack system levels is essential to meet these requirements, material-level research plays a critical role and should be prioritized. This feature article presents a comprehensive overview of design and synthesis approaches for cathode and anode materials, emphasizing improvements in energy density, cycling stability, and rate capability. Key material candidates for current and future LIBs and SIBs include layered transition metal oxides, spinel-type structures, and phosphate-based compounds. However, meeting the demands of next-generation batteries requires overcoming considerable challenges related to capacity, rate capability, and long-term stability. Anodes, including alloy- or conversion-type materials and carbonaceous anodes, are promising candidates for both LIBs and SIBs. Yet, key issues such as volume changes caused by electrochemical reactions with Li and Na ions, unstable solid electrolyte interphases, and limited rate capability still need to be resolved. In this feature article, we review effective strategies-highlighting our own efforts-to tackle these challenges. Additionally, we suggest synergistic approaches combined with electrode material design and outline future research directions focused on achieving high-energy, high-efficiency, and highly stable next-generation batteries.