Wiktionary
a battery
n. (context dated electronics English) A battery used to heat the filament or cathode heaters of electron tubes.(R:RHCD: page=1)
Usage examples of "a battery".
Hunt answered from a leather-upholstered easy chair in front of a battery of display screens on the opposite wall.
The entrance they came to was a transparent wall and set of doors opening from a wide pedestrian precinct lined by stores and what looked like office units, rows of display cases, and at the far end a battery of stairs and escalators going up to the concourse of a transportation terminal.
It was sent on its way by a battery of laser cannon set up on Phaeton, an asteroid whose orbit takes it closer to the sun than Mercury.