Preface for the 71st Special Feature “New Progress of Batteries and Fuel Cells” — Getting Off to a Fast Restart

This special issue of Electrochemistry features selected papers from the 65th Battery Symposium in Japan, held in November 2024, which marked a full return to in-person meetings after the COVID-19 pandemic. The symposium saw record participation, highlighting strong interest in lithium-ion batteries, all-solid-state batteries, and emerging chemistries such as sodium-ion and lithium–sulfur systems. Progress in electrolyte design, interfacial science, and data-driven approaches was also emphasized. Additionally, several contributions focused on fuel cell research, reflecting the expanding scope of electrochemical energy technologies. We hope this collection stimulates further innovation in energy storage and conversion.