Electronic device including thermal diffusion member

An electronic device comprising:

• a display;
• a rear cover;
• a housing at least partially disposed between the display and the rear cover such that a first surface of the housing faces the display and a second surface, opposite to the first surface, faces the rear cover, the housing comprising a placement space formed therein and a support portion formed on the second surface, the support portion comprising a first support portion extended in a first direction perpendicular to the second surface and a second support portion extended from the first support portion in a second direction perpendicular to the first direction;
• a thermal diffusion member at least partially disposed in the placement space;
• a printed circuit board at least partially disposed in an interior of the housing at a first side facing a third direction between a first diffusion portion of the thermal diffusion member and the rear cover, the third direction being opposite to the second direction with respect to the first support portion;
• and
• a battery at least partially disposed at a second side facing the second direction with respect to the first support portion between a second diffusion portion of the thermal diffusion member and the rear cover, the battery comprising a first battery portion having a first thickness and a second battery portion extended from the first battery portion in the third direction, the second battery portion having a second thickness less than the first thickness,
• wherein the second battery portion is at least partially disposed between the second support portion and the rear cover, and
• wherein the second support portion is at least partially disposed between the second diffusion portion of the thermal diffusion member and the second battery portion.