Lithium metal is a soft, silvery-white alkali metal that is highly reactive and flammable. It is the lightest metal and has a low density, making it useful in various applications. Lithium is primarily used in rechargeable batteries, particularly in lithium-ion batteries, which power many electronic devices like smartphones and laptops. In addition to its role in batteries, lithium metal is also used in the production of certain alloys and in the pharmaceutical industry for treating mood disorders. Its unique properties make it an essential element in modern technology and medicine, contributing to advancements in energy storage and mental health treatment.