A Survey on the Affordances of “Hearables” <s> Battery Life <s> Wireless charging is a technology of transmitting power through an air gap to electrical devices for the purpose of energy replenishment. The recent progress in wireless charging techniques and development of commercial products have provided a promising alternative way to address the energy bottleneck of conventionally portable battery-powered devices. However, the incorporation of wireless charging into the existing wireless communication systems also brings along a series of challenging issues with regard to implementation, scheduling, and power management. In this paper, we present a comprehensive overview of wireless charging techniques, the developments in technical standards, and their recent advances in network applications. In particular, with regard to network applications, we review the static charger scheduling strategies, mobile charger dispatch strategies and wireless charger deployment strategies. Additionally, we discuss open issues and challenges in implementing wireless charging technologies. Finally, we envision some practical future network applications of wireless charging. <s> BIB001 </s> A Survey on the Affordances of “Hearables” <s> Battery Life <s> A novel and scalable self-charging power textile is realized by combining yarn supercapacitors and fabric triboelectric nanogenerators as energy-harvesting devices. <s> BIB002
Battery capacity plays a major role in the design of wearable computing devices, and hearables are no exception. Battery life of ear-mounted wearables tends to be shorter than other types of wearables, and many models are sold with carrying cases that double as portable charging solutions. When in continuous use, battery life for most hearables is typically not longer than 5 h  , thus limiting their ability to be worn all day long. Similar battery life issues have been overcome in the design of smart wristwatches  . If hearables are to properly blend into the background of everyday life, advances in battery technology, wireless charging BIB001 wireless protocols, or self-charging devices BIB002 will be required.