An electromagnetic navigation system having a wireless, battery-powered medical tool is provided. The system charges the medical tool using energy from the same magnetic fields used to locate the tool in 3-D space. The system includes one or more wireless transmission devices which generate the magnetic fields. The medical tool includes a receiving coil which generates electrical signals indicative of a location of the tool in response to receiving the magnetic fields. The tool also includes a wireless interface which provides electrical signals for processing to determine the location of the tool in 3-D space and a battery which supplies power to the tool. The tool also includes one or more charging coils, electrically connected to the battery. Each charging coil receives energy from the magnetic fields passing through a charging coil surface and supplies the energy to the battery to charge the battery.
