Wireless charging for devices with metal housings

A device comprising:

• a wireless power receiving coil and an associated coil core, wherein the coil core defines a center opening that extends through the coil core, the wireless power receiving coil surrounding the center opening in the coil core;
• a housing comprising one or more metal portions, wherein the housing is configured to receive at least a portion of the wireless power receiving coil and the associated coil core in an opening defined by the one or more metal portions;
• and
• an alignment feature that is located at a center of the wireless power receiving coil, in the center opening that extends through the coil core, the alignment feature configured to interact with a magnet of a wireless charger to align the device with the wireless charger, wherein the alignment feature comprises a plurality of magnetic metal elements that are electrically insulated from each other.

A electronic watch device comprising:

• a display screen;
• a wireless power receiving coil and an associated coil core, wherein the coil core defines a center opening that extends through the coil core, the wireless power receiving coil surrounding the center opening in the coil core;
• a sensor located in the center opening of the coil core;
• a center window configured to permit external light to reach the sensor located in the coil core;
• and
• a housing that retains the display screen and receives at least a portion of the wireless power receiving coil and the associated core, the housing comprising a plurality of metal portions that form part of an underside of the watch device that is opposite the display screen and that is configured to contact user skin when the electronic watch device is user worn, the plurality of metal portions including a first semi-circular metal portion and a second semi-circular metal portion that are electrically isolated from each other and that at least partially surround the center window.