In military organization, a battery is a unit comprised of artillery and other heavy weapons. Their task is to provide long-range fire support for weaker units, such as infantry and tanks.
The Dominion organized ships into batteries. Such units were used by Gul Dukat during the Second Battle of Deep Space Nine and were critical in bringing down the station's shields. (DS9: "Call to Arms")
In 2371, Neelix claimed to Kes that he had "gazed into the gaping maw of death – during the Battle of the Pyrithian Gorge I faced down an entire battery of Haakonian artillery." (VOY: "Jetrel")