A battery - battery used to heat the filaments of a vacuum tube

B battery - battery for supplying a constant positive voltage to the plate of a vacuum tube

C battery - battery used to maintain the grid potential in a vacuum tube

electrical device - a device that produces or is powered by electricity

electrode - a conductor used to make electrical contact with some part of a circuit

terminal, pole - a contact on an electrical device (such as a battery) at which electric current enters or leaves

galvanic battery, voltaic battery - battery consisting of a number of voltaic cells arranged in series or parallel

galvanic pile, voltaic pile, pile - battery consisting of voltaic cells arranged in series; the earliest electric battery devised by Volta