The Power Cell is used in the construction of power-producing blocks.
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.
Usage[]
Power Cells are always needed -- to build batteries in early game stages, then to build Hydrogen Engines in mid game, and for finishing a 
Jump Drive block in late game.
Railguns and Jump Drives are considered "power producing blocks" even though they do not output power for the player, but only for their internal capacitors.
A Power Cells require only early-game ingredients such as 
Iron Ingot, 
Silicon Wafer, and 
Nickel Ingot. As of version 157013, 
Cobalt is no longer needed, making batteries a more feasible source of energy for planetary start endeavors.
Construction[]
Power Cells are required to construct the following blocks:
