Shock gloves

The Shock Gloves are a pair of gauntlets that can emit electricity and that first appeared in Batman: Arkham Origins. They were originally worn by the Electrocutioner before being in Batman's possession after the former's death.

Origin
The Shock gloves are first seen during Electrocutioner's first appearance on the game, when he is seen using them to kill his enemies during the assassin introduction cutscene at the beginning of the game. The first time the player actually sees them in action is during the confrontation between Batman and the Electrocutioner inside the Final Offer. The last time they are seen on Electrocutioner's person is when Batman gains access to the surveillance systems and sees the Joker push the villain out of a window and sending him falling to his death, landing right next to Batman. It is then that the Shock gloves actually become usable as we see Batman retrieving them from Electrocutioner's corpse.

Combat
One of the main abilities of the Shock Gloves is that they can transform kinetic energy into electric energy in order to help them charge up. If Batman is able to beat up enough thugs and fully charge the shock gloves' batteries, He can activate them at will. Once activated, the Shock Gloves are able to boost the strength of each attack, making hits powerful enough to knock down enemies with a single blow, punch through shields and armor without needing to cape stun the enemy first, and take out armored opponents using significantly less blows. The battery depletes after each hit, eventually turning off the gloves when empty and returning Batman's punches to normal. It also depletes automatically after a combat session is over.