battery

The battery can be:

in technology:
a system of (almost) identical machines or devices forming a single unit, which serves to increase performance, work effect and the like, e.g.:
furnace battery
anode battery
the parallel or series connection of galvanic or battery cells to obtain a direct current source of higher voltage or higher capacity, usually manufactured as a whole; see Galvanic Cell#Connecting Galvanic Cells
electric battery

solar battery (= solar generator, solar battery; connecting a large number of solar cells to produce electricity from solar energy)

according to IEC 60050-482: one or more electrochemical cells equipped with elements necessary for use, e.g. housing, pole terminals, markings and protective elements
somewhat imprecise from a professional point of view: (dry) galvanic cell for portable radio-technical and similar equipment; colloquially, any galvanic cell or source of direct current; colloquially also called flashlight; see galvanic cell
a primary electrochemical cell or a set of such cells
in nuclear energy: abbreviated atomic battery (= nuclear battery; a device for the direct conversion of the energy of radioactive material into electrical energy using a converter)

in construction:
abbreviated mixing faucet (set of water valves for mixing cold and hot water)

in panel production: see battery (panels)
in agriculture: form of chicken coop, see battery (chickens)
in the military:
the smallest unit of rocket troops, ground and anti-aircraft artillery, see battery (artillery)
a set of several works designed for combat

in music: a set of percussion instruments of a musical group or orchestra

in chess: the position of two or more line pieces of the same color on one line on which they all act, see battery (chess)

in psychology: abbreviated battery of tests (a complete set of psychological tests, the results of which are combined)

colloquially: a large number of things of the same kind, e.g. battery of bottles