The Lighting shield (or Ion Shield, or L-Shield) was a Carthaginian shield system based on their technology capable of creating and controlling the most violent ion storms. It was built for their starships to simulate an ion storm, while simultaneously acting as a defense against most weapons-based technology and the like. (Star Trek: Phoenix-X)
The shield acts as a bubble around any given starship, in that ion-based "electricity-bands" spark up and around the ship randomly.
Carthaginian vs StarfleetEdit
The Lighting shield technology is 45% stronger than standard Starfleet shielding in the late 24th century. It protects against many elements a Starfleet shield can, but also has its faults in that it cannot protect against everything. In that way, the shielding is not always reliable; but on the whole is still considered slightly more effective than Starfleet shields, depending on the situation.