a 'dead battery' = ('Brit') a 'flat battery' [=a battery that has no more electricity]
The operation was performed by a 'battery' of doctors.
He was found guilty of 'battery'.
(..) - Don't bother. See this crap? Somebody knows I'm talking to you. Not according to the men in blue. Is it kiddie porn again? Sexual battery of a patient? - They wanna discredit you. Why? - Because I know too much about the truth. That end-of-the-world garbage you write? You know my work? (..)1998 The X Files