Power feeding device, power receiving device, and wireless power transmission device

A power receiving device to which power is transmitted wirelessly from a power feeding device, comprising:

• one or more power receiving units including a secondary coil and a magnetic body, the secondary coil including:
• (a) a winding portion formed by a wound conductive wire;
• (b) an opening portion which is surrounded by the winding portion;
• (c) at least two planar portions, each planar portion including
• (i) a part of the winding portion and
• (ii) a part of the opening portion which is partially surrounded by the part of the winding portion;
• and
• (d) connecting portions that connect together the at least two planar portions,
• wherein each part of the opening portion of the secondary coil is disposed along a different one of two or more surfaces which form the outer shape of the power receiving device and are not parallel to each other, the two or more surfaces including (a) a first face that faces a surface in which a primary coil of the power feeding device is disposed and (b) a second face adjacent to the first face;
• and
• the magnetic body is disposed along the at least two planar portions of the secondary coil, each of the at least two planar portions being between the magnetic body and a different one of the two or more surfaces.