Fuel Cells are a collectible item in Star Fox Adventures. Their purpose is to power-up Fox's Arwing, so he can reach the four SpellStone locations on Dinosaur Planet. There are 75 of them scattered all over Sauria, where they were dropped by R.O.B. 64, who had a few problems getting them to the surface. They can also be bought in ThornTail Store for ten Scarabs each. Only 42 are needed to finish the game however: five to reach the DarkIce Mines, ten to make it to the CloudRunner Fortress, 12 to land into the Walled City and 15 to get to the Dragon Rock. Fox can carry a maximum of 255 Fuel Cells at a time. They are dark blue, sparkling head-size spheres in appearance.
Star Fox Command
In Star Fox Command, the Fuel Cells add 25 seconds to a character's timer. Their appearance has changed significantly from Star Fox Adventures. They are green orbs with a smaller, purple sphere speeding around them. They can be found in missions, often hidden by fog of war, on the main map. They can also be retrieved from enemies.