Lithium iodide is widely used in solid-state batteries due to its high ionic conductivity when doped with small amounts of other salts like aluminum iodide. It serves as a key component in some types of thermal batteries and long-life batteries for extreme environments, such as aerospace and military applications. Its ability to conduct lithium ions while remaining electronically insulating makes it suitable as a solid electrolyte in experimental battery systems.

It is also used in radiation detection instruments, particularly in scintillation counters, where it can be doped with europium to detect gamma rays and X-rays efficiently. The compound’s hygroscopic nature and stability under certain conditions make it useful in specialized moisture-sensitive applications, though handling requires care due to moisture sensitivity.

Additionally, lithium iodide has been explored in organic synthesis as a catalyst or reagent for iodination reactions and carbon-carbon bond formation under mild conditions.