Lithium iodide hydrate is widely used in organic synthesis as a catalyst, particularly in reactions involving the formation of carbon-carbon bonds. It is also employed in the preparation of electrolytes for high-temperature batteries, where its ionic conductivity properties are highly beneficial. In the field of medicine, it serves as a source of lithium ions in certain pharmaceutical formulations, particularly for treating bipolar disorder. Additionally, it is utilized in humidity sensors due to its hygroscopic nature, which allows it to accurately measure moisture levels in the environment. In some specialized applications, it is used in optical materials and as a dopant in certain types of glass to modify their refractive index.