We say the sodium ions have been discharged. As the sodium ions gain electrons, reduction occurs at the cathode. Tiny globules of molten sodium float to the surface of the molten sodium chloride and burn in air with flashes of yellow light.
What happens at the anode (+)?
Electrons flow out of the anode back to the battery. The anode is therefore positively charged. The negative chloride ions (anions) are attracted to the positively charged anode. At the anode, the chloride ions give up electrons to the electrode to from chloride atoms.