You already know it from electric toothbrushes or smartphones: simply set the device down or put it in the corresponding holder and the batteries begin to charge. With inductive charging technology, electrical energy is transferred from one object to another contact-free in order to operate or supply the latter object. The essential feature is that the electrical energy required for operation is not supplied by using cables and electrical contacts, but rather by wireless electromagnetic fields.
In order to charge devices via induction, their power cells must be connected to a special receiver coil. A second coil required for the transmission is located in the charging station. If the device is placed on the station, the charging process starts automatically. Proximity matters because the maximum distance must correspond to approximately the radius of the coils in order to ensure an optimal transfer of energy. In the vicinity of up to a few centimeters — as is the case with toothbrushes, smartphones and hearing aids — the technology works with a comparably high degree of efficiency (approximately 90 percent).
The advantage of this technology is convenience. You can easily charge your hearing aids when you do not need them (e.g., overnight). The charging process is very simple, since all you have to do is place the hearing aids in the supplied charging dock. In addition, the batteries don’t need to be replaced regularly, which is not only more convenient, but also reduces costs and protects the environment.