17.4 Environmentally-Friendly Disposable Circuit and Battery System for Reducing Impact of E-Wastes.

The era of Internet of Things (IoT) is arriving as electronic devices have become ubiquitous. Engineers have incorporated various harmful substances and scarce elements into electronic devices for improving their performance. Disposable uses cases, such as moisture sensors or thermometers, are also increasing. As a result, a large amount of electronic devices causes electronic and electrical wastes (e-wastes), and this has become a global environmental problem. When the electronic devices are discarded without recycling, the harmful substances in them pollute the soil and water (Fig. 17.4.1). In addition, the use of scarce elements deplete resources, causing economic conflicts. For a sustainable society, disposable electronic devices should use only materials that do not harm the environment or deplete resources.