For the purpose of improving energy efficiency or improving sound quality, there is provided a cable, a power supply tap, a battery, a printed circuit board, a LSI/IC and the like comprising a hygroscopic fiber, an inorganic ion exchanger influence fiber, a supercritical influence fiber, a composite fiber obtained by mixing two or more among the mentioned fibers, or a hygroscopic resin, an inorganic ion exchanger influence resin, a supercritical influence resin, and a composite resin obtained by mixing two or more among the mentioned resins, and a power supply method of supplying power to a device or a battery.