Many of its salts are hygroscopical and corrosive, and should be handled with precautions. The element has limited applications, being important its use in vacuum tubes and photocells. Rubidium carbonate is sometimes used in the glass industry. It is also extensively studied as a potential heat transmission material in space vehicles, as fuel in motors of ionic propulsion, as electrolyte in low temperature alkaline batteries, etc. Some rubidium compounds are used in preparing soporific, sedatives and in the treatment of epilepsy.