embodiment a secondary battery may be formed in a lower portion and connected to a power supply voltage line so that a power supply voltage can be transmitted to a plurality of pixels formed on the display panel the voltage generated by the secondary battery typically ranges from 3v to 5v while the voltage applied from the power supply voltage line to drive each of the pixels typically ranges from 4v to 5v as a result the oled display device according to an exemplary embodiment can apply the voltage generated by the secondary battery located in the lower portion to each pixel without requiring an additional voltage controller such as a dc dc converter furthermore in the oled display device according to an exemplary embodiment since an electrolyte layer of the secondary battery is formed by a solid electrolyte the secondary battery may be obtained through a deposition process typically used to fabricate an oled display device therefore a semi permanent power supply may be installed inside the oled display device without the use of additional apparatus so that even if an external power supply voltage is interrupted the oled display device can be driven for a predetermined amount of time according to the embodiments described above a secondary battery can be formed through a fabrication process typically.