Energy Cell

Energy Cells are small green cylinders that appear in Metroid Prime 3: Corruption. They are used to open doors and run machinery on the G.F.S. Valhalla. When the Space Pirates invaded the ship, killed every tripulant and took Aurora Unit 313, they took all Energy Cells so that they could use them as energy sources for other machines. This means that the Cells were carried to several planets. There are nine scattered throughout the worlds; not all are required to beat the game, but they are if the player plans to complete it with 100%.

Locations
In the G.F.S. Valhalla, several data computers managed to locate the missing Cells. Their locations can be checked in the inventory. This helps Samus to know where to retrieve them. The Energy Cells are the final key item quest in the game, in the same way the Chozo Artifacts (in Metroid Prime) and the Sky Temple Keys (in Metroid Prime 2: Echoes) were. Samus finds some of them during her travels without knowing yet their usage, but needs them to gain access to multiple areas of the G.F.S. Valhalla, including one containing the vital clue to enter Phaaze, the source of all Phazon and the final level of the game. Something that makes the Cells different from the Artifacts and the Keys is that, because of their connection to machineries, their removal causes beneficious side effects. The Cells' locations are (ordered by planet, not according to the data storage):


 * Generator B in Norion, the only part of the planet that Samus doesn't explore at first (this is because Rundas already activated the generator during the initial invasion). The area is protected by a Metroid Hatcher, and removing the Cell from its spot re–opens the entrance door (it initially closes after Samus enters the room).


 * Hangar Bay in Bryyo, it can be taken when Samus Aran's gunship is about to receive the Ship Missile upgrade. Removing it from its spot shuts off a force field blocking the way to the Hall of the Golems.


 * Hidden Court in Bryyo, arguably the most difficult to obtain in the game, because its collection requires the connection of two entire regions of Bryyo and the careful carrying of extremely heavy objects (with the help of the Ship Grapple). No notable side effects occur.


 * Xenoresearch Lab in Elysia. Samus is forced to remove it from its spot in order to obtain the Seeker Missile launcher.


 * Ballista Storage in Elysia, the same battle arena where the Defense Drone is fought (however, collection of Grapple Voltage on Pirate Homeworld is required). Removing it just leaves the cooling system offline.


 * Command Courtyard in Pirate Homeworld, mandatory to collect (in order to turn off some fans and gain access to the Flux Control area).


 * Metroid Processing in Pirate Homeworld, it can be taken during the search of a missing soldier. Removing it frees the imprisoned Metroids, and a Missile Expansion can be collected.


 * Phazon Quarry in Pirate Homeworld, it can be taken after collecting the Nova Beam, and doing so removes an energy barrier, which gives Samus a shortcut to exit the mines more quickly.


 * Docking Bay 5 entrance on the wrecked G.F.S. Valhalla. It is not powering any station and is just lying under a smaller crashed ship.

Trivia

 * An Energy Cell is found on G.F.S. Olympus and is used to keep a certain room functional. However, this Cell always belonged to that ship, not the G.F.S. Valhalla. This means that there are actually 10 Cells in the game.


 * Interestingly enough, when Samus is looking for Bryyo's second Cell and is carrying through her gunship the head of a giant Mogenar, and she tries to place it on the body of the statue, her Command Visor says that there are no valid targets in the area. This is incorrect,as the Mogenar statue is a target, and players who don't notice the mistake will remain confused. It is unknown why the Visor made that advice, but it is possible that it is a glitch.


 * Bryyo is notably the only planet whose Cells are found in the same major area. The ones located in both Elysia and the Pirate Homeworld are distributed equitably across their main segments.


 * Five Cells are required to clear the game, but there is a glitch (involving the use of the Screw Attack and respawning from a fall onto a distant ledge) that helps the player to do the same with only three.


 * Energy Cells distinctly resemble Afloraltite crystal containers from the Metroid Manga, suggesting that that might be what Energy Cells contain.