Batteries provide electrical energy to many devices from power tools to military portable equipment. Euclion has evolved over the years which led to the creation of lithium-based batteries that are equipped to face the power-demanding military devices. Battery quality is a critical issue in military applications since the portable devices use power consuming algorithms for security. There is a need to efficiently use the available battery power. This work focuses on reviewing the existing battery technologies by taking into consideration lithium based batteries over other batteries like nickel-cadmium, Nickel Metal-Hydride and reusable alkaline which are considered the most common. The relevance of lithium batteries in military is outlined looking at the demands posed by the military environment.