Abstract: A wireless charging device may be worn as a wristband wearable on a user's wrist. The device includes one or more energy collection components located on the wristband. The energy collection components may collect ambient energy and convert the ambient energy to electrical energy. One or more energy storage components located on the wristband and electrically coupled to the energy collection components may store at least some of the electrical energy from the energy collection components. One or more energy transmission components may be located on the wristband and electrically coupled to the energy collection components and the energy storage components. The energy transmission components may wirelessly couple with a mobile device to wirelessly transmit at least some of the collected electrical energy to the mobile device for charging a battery on the mobile device.