Cost effective and compact thermal energy storage systems that enable passive, non-powered, repeatable storage and release of heat could offer significant tactical and practical advantages for soldiers mission execution and success in a deployed setting of cold climates. Sorbent systems can store heat indefinitely, however, current sorbent-based technologies require storage tanks and complex controls that are costly and difficult to operate and maintain. We will develop an innovative smart thermal battery technology whereby a sorbent material is paired with smart materials that can be engineered such that the sorbent stores heat using adsorption-desorption principles. The stored heat can then be released in a passive, time-controlled way when encountering an external thermal stimulus. Theoretical and experimental work will be performed to gain a better understanding of material characteristics and coupled heat-mass transport processes that affect system performance. we will focus on heat storage and release for providing cold climates protection to soldiers as light, compact built-in heating elements in their garments. Experiments will be performed to evaluate key system characteristics and provide guidance for engineering a prototype system. STTR funding will allow the team to enhance the understanding about the critical system requirements, and to pursue additional private and public funding.