Revolution of iodine electrochemistry: From I−/I2 to I−/I5+

Iodine electrochemistry involving multielectron transfers provides higher energy density while encountering challenges due to sluggish kinetics and unstable intermediates. This Preview highlights a recent work by Li et al. in which an unprecedented iodine electrochemistry of I−/IO3− is precipitated by highly concentrated hetero-halogen electrolytes. Such iodine electrochemistry enables a fast six-electron-transfer redox process, contributing to the commercialization of high-energy-density aqueous batteries for grid-scale energy storage. Iodine electrochemistry involving multielectron transfers provides higher energy density while encountering challenges due to sluggish kinetics and unstable intermediates. This Preview highlights a recent work by Li et al. in which an unprecedented iodine electrochemistry of I−/IO3− is precipitated by highly concentrated hetero-halogen electrolytes. Such iodine electrochemistry enables a fast six-electron-transfer redox process, contributing to the commercialization of high-energy-density aqueous batteries for grid-scale energy storage.