The Army is facing a number of challenges now and in the future. One of the major challenges is in the power sources arena. As the Army continues to move toward digitizing the battlefield, the need for portable power is increasingly becoming a technological hurdle that must be overcome in order for a soldier to exercise his electronics capabilities without being overburdened by the power sources size, weight and operating/logistical costs. Advanced electronic devices are becoming a critical piece of the soldier's personal battlefield equipment. A soldier with the latest version of the Single-Channel Ground and Airborne Radio System (SINCGARS) is one of the most dangerous weapon systems on the modern battlefield. The ability to accurately navigate and communicate multiplies the soldier's advantage over a less electronic capable enemy. Keeping his personal electronics operational is crucial to giving the soldier the capability to complete his mission successfully. Inherent in keeping the electronic equipment operating is keeping it supplied with batteries. Due to the increased emphasis placed on the modern soldiers electronic equipment, the importance of the portage of the power sources needed to keep this equipment operational has also increased. Recent efforts have focused on hybrid power sources that may enhance discussed capabilities by taking advantage of both high energy sources and high power systems for intermittent power application. This development could lead to a power source with enough energy to meet the Army's preference for a 72-h mission life before the need for resupply. Published by Elsevier Science S.A.