Trends in metal-air battery research: Clusters, and future directions

Metal-air batteries (MABs) have gained substantial attention as a promising energy storage technology due to their high theoretical energy densities and potential applications in sustainable power systems. This study employs a scientometric approach to analyze 4035 research papers, mapping the intellectual structure, collaboration networks, and emerging research themes in MAB development. By utilizing bibliometric tools, we identify key research clusters spanning electrochemical energy storage, electrocatalysis, and computational modeling, highlighting the evolution of scientific focus over time. The analysis reveals a progressive shift from fundamental battery chemistry toward the integration of nanostructured materials and bifunctional catalysts, aiming to enhance efficiency and durability. Keyword trend analysis underscores an increasing emphasis on oxygen reduction reaction (ORR) mechanisms, electrolyte stability, and material sustainability. Furthermore, the geographical distribution of research output demonstrates that China, the United States, and South Korea are leading contributors, with emerging participation from Singapore and Australia. Despite significant advancements, challenges such as limited cycle life, electrode degradation, and manufacturing scalability remain persistent. Addressing these limitations requires continued interdisciplinary collaboration and innovative material engineering. This study provides a data-driven perspective on the current state and future directions of MAB research. By identifying knowledge gaps and research frontiers, these insights serve as a strategic guide for scientists, policymakers, and industry stakeholders seeking to accelerate advancements in next-generation energy storage solutions.