Originally, the Sinestro Corps Central Power Battery was built on Qward.
The Central Power Battery serves as a repository for the yellow energy of fear. Sinestro Corps rings must be recharged every 24 hours. Every personal power battery draws its energy from the Central Power Battery.
During the Sinestro Corps War, Sinestro put the battery aboard Warworld to help in the Earth Invasion. The Central Power Battery was destroyed when it was pulled, along with Warworld, by the Green Lantern Corps on top of the Anti-Monitor resulting in a massive explosion. Yet Sinestro Corps rings still possessed their powers without any sort of deficiency. Making it questionable whether their was more then one battery or if the rings are designed to run on ambient energy generated by fear in general. It was later revealed that Sinestro had built a secondary Central Battery and left it hidden on Qward, in the event that the Invasion of Earth failed.
Mongul, in his attempt to usurp the Corps, had a Sinestro Corps Power Battery as part of his invasion of Daxam. He had the Central Power Battery moved to Korugar in order to set up a new homeworld for his Corps. Wanting to protect his home planet and take back his Corp, Sinestro defeats Mongul and seals him away inside the Sinestro Corps Power Battery.
Green Lantern: First Flight
In the movie, the Yellow Power Battery hoovers around as it serves Sinestro alone. This too was forged on Qward. It's many attacks were against The Guardians, Oa, and The Central Battery. Once Hal absorbs the Central Battery, he knocks the Yellow Battery around into orbit until Sinestro arrives and attacks with it. The Yellow Battery becomes destroyed however when Hal collides two moons together creating the battery to burst.