Power Cell
The Power Cell is used in the construction of power-producing blocks. In this context, Railguns and Jump Drives are considered "power producing blocks" that need power cells even though they do not output power for the player, but only for their internal capacitors.
Important: When you grind Batteries, the Power Cells are not returned to your inventory like other components, but turn into Scrap Metal! Batteries are partially charged after they were built, and losing the Power Cells components is the cost for the free charge. Grinding other blocks (Hydrogen Engines etc.) returns the Power Cell components intact into your inventory. Remember this when redesigning a starter pod (you cannot simply move a battery without having assembled extra Power Cells first!) or when hacking batteries on enemy ships.
From early game on, Power Cells are needed to build batteries, then to build Hydrogen Engines in mid game, and for finishing a Jump Drive block in late game. Power Cells require only early-game ingredients such as Iron Ingot, Silicon Wafer, and Nickel Ingot.
Construction
Power Cells are required to construct the following blocks: