Energy Crystal (IndustrialCraft 2)

The Energy Crystal is a rechargeable energy storage unit added by IndustrialCraft 2 which is similar to an RE-Battery or Lithium Battery. It can hold 100,000 EU. It requires an HV-tier interface to charge. Right clicking an energy crystal will NOT cause it to recharge electrical powered items in your inventory.

Uses
The Energy crystal is used as a power storage unit much like an RE-Battery.

It is also used as a crafting ingredient for MFEs, Nano Armor, Lapotron Crystals, and other third-tier electric items.