Answer:
Helios was a Greek Titan god of the sun; the sun itself -it's movements over the sky.
He was called:
Hyperionides (Son of Hyperion, He Who Goes Above)
Thus was mistaken for Hyperion later; or simply called it as the sun movements are above.
His nature as a Titan was also a name.
Elector (The Beaming)
Eleutherius (Of Freedom)
Soter (Savior)