An impulse capacitance cell was an energy storage device connected to the impulse drive in starships such as the Intrepid-class. It held enough power for a single short impulse burst during emergency situations. In 2371, B'Elanna Torres released power from the USS Voyager's impulse capacitance cells into its driver coils in the hopes of breaking free from a magnetic wake generated by a swarm of space-dwelling lifeforms. (VOY: "Elogium")