Regenerative phaser

Regenerative phasers were a type of weapon developed by Starfleet in the 24th century.

The TR-116 rifle project was abandoned in favor of regenerative phasers. 

In 2381, regenerative phasers were used against the Borg at the Battle of Acamar during the Borg invasion. The regenerative phasers failed, a fact later relayed to Admiral Elizabeth Shelby by Captain Holly Hostetler Richman.