Really love the ideas guys, Phi for All I think your idea about the suit gaining energy from the force of attacks and other kinetic energies is really good, powering from its defense, it sort of reminds me of Bruce Lee saying that his offense and defense are the same thing. Also, the idea of the wearers blood being used to power the suit at a minimum level or more which both Phi for All and Endy0816 mentioned is quite an interesting idea, the thought never even crossed my mind. With the suit being powered through kinetic means while simultaneously being back up by the wearers own blood stream I think the question of powering such a suit has been answered. Maybe the inside of the suit holds numerous points that pierce the flesh connecting the suit directly to the veins which then fills the suits artificial veins with blood which flows to and from your body literally turning the suit into a part of your own body, not sure, have to think that through, you might not ever be able to remove the suit again once worn if I make it that way, which could be a cool consequence.
In the story the suit will be called the Kirasa Secondskin Smartsuit, KSS for short. Secondskin as the term implies because it will fit snug and tight acting as a thick protective second layer of skin. Smartsuit because the original idea was for the suit to be able to sense radiation, and extremes in temperature, and would automatically change its own functions to make it safe for the wearer leaving them unaffected by whatever they face, thus leaving consumers saying that's a smart suit, it thinks for itself (technically its been preset with the ideal conditions for man so it tries its best to meet those conditions no matter the environment, I think I might need some kind of cybernetics for this suit to function with the think for itself premise). And Kirasa is a Russian company that has made serious advances designing present and future military attire. So in my world around 2042 they design the KSS for the military to search and explore the frozen, radiated, disease ridden post apocalyptic surface of the planet to search for worthy specimen of a new species to bring back for the newly unified government of the Earth's scientists to study from there Subterrainian Utopia that all the "important" people in human society now call home, leaving the rest of us not so important commoners on the surface to die. This is why I needed a bodysuit with those functions because half of the planet is frozen, there is an alien pathogen that has been introduced into the earths atmosphere and oceans, only 4 continents remain, dust clouds have blocked the sun and moon for years killing all natural vegetation, and 85 percent of life that remains on the surface of the planet is now something more than man and beast. So the KSS must be able to have the military function unaffected by such conditions. Oh Endy0816 I will research different nano-tech materials to try and come up with an adaptation that is a useable fabric for the suit, and your idea for a mind machine interface to control the suit is one I will definitely look into because designing a suit that controls its own functions might be tricky if its not a computerised Ironman suit. Phi for All your idea for the suit being its own battery is great and exactly what I was thinking, but it will be worn in a world with no sunlight so that idea might not work out, how could your idea about using seawater to power the suit work?