"Battery" is the opening track of Metallica's 1986 album Master of Puppets. It begins with acoustic, classical guitar before becoming a very fast thrash metal song.

In keeping with the general "control" theme of Master of Puppets, the lyrics of "Battery" discuss the control that anger can have over one's behavior. The title refers to "battery" in the sense of "assault and battery", as shown by these lyrics: "Smashing through the boundaries / Lunacy has found me / Cannot stop the battery".

"Battery" was adapted for Metallica's 1999 S&M concert; it was used as the encore. It is an almost constant part of the band's live set-list. It is frequently the opening or closing song-on their current world tour it has been replaced as the set opener by Blackened.