Development of low-temperature high-voltage electrolytes for thermal batteries

Thermal batteries serve as ultra-reliable electrical power sources in guided munitions, missile systems, and some emergency escape systems. These batteries have very long storage lifetimes, in excess of 20 years, due to an electrolyte that is solid and non-conductive to ions at ambient temperatures. The battery is active when the electrolyte is melted using a pyrotechnic device. Conventional electrolytes operate at high temperatures approaching 600 degrees C. This temperature represents a challenge to systems engineering as the run time of the battery is short from fast cooling and nearby components can overheat. Boulder Ionics, in a partnership with a leading thermal battery manufacturer, proposes to develop a new class of electrolyte that melts between 100 and 150 degrees C and has an electrochemical window of 5 V. These characteristics will increase the run time and energy capacity of thermal batteries enabling longer missions in a more compact package.