When U.S. soldiers routinely undertake a three-day mission, they need to carry: food, water, ammunition, and—10 to 13 pounds of batteries. Modern soldiers have many electronically powered devices, such as night vision goggles, flashlights, and radios, and batteries are an essential tool for them during missions.
In fact, the sheer number of batteries they had to carry severely hampered soldiers' mobility due to their weight. Frequent resupply needs meant that more soldiers had to risk their lives just to deliver batteries to those in need. To alleviate this problem, the military required soldiers to wear athletic, durable uniforms with solar panels and bionic knee pads, which could be charged at any time using solar and kinetic energy.
“If we can reduce our need for batteries, we will significantly reduce fuel costs. Previously, these expenses were needlessly wasted on battery transportation,” said Chris Hurley, head of the battery development team at the U.S. Army Communications Electronics Research, Development and Engineering Center. “We are also saving lives because there are many dangers in transporting supplies on the battlefield.” The knee brace has little medical value, but Garcha says it will not affect soldier mobility. If the knee brace doesn't serve that purpose, then it's pointless. Each knee brace can generate 10-12W of power per hour, enough to charge roughly three smartphones. This helps replenish power, but it cannot completely replace all the functions of a battery for now.
However, before soldiers don their solar panel uniforms, the military must ensure that these new uniforms, like the old ones, do not shimmer in the sunlight and attract snipers' attention, or emit heat that would be detected by enemy infrared detectors. These are all deadly on the battlefield.
Zero weight is likely a perpetual goal for the U.S. military. As new equipment is developed and older equipment is upgraded, soldiers' demand for power will gradually increase. Therefore, the U.S. military is also seeking manufacturers of more efficient static batteries and is researching solutions to allow soldiers to control their energy supply.
