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Secondary b., one in which chemical energy is stored and produces an electric current for a considerable period.

A battery having two plates of lead or other material immersed in an electrolyte; when these are charged with a current of electricity they become negative and positive, and when a connection is made the current flows from one to the other as between the poles of a galvanic battery; accumulator. See cut under battery.

Apparatus for storing electricity.

secondary or galvanic accumulator. A galvanic b. with lead plates as electrodes and dilute sulphuric acid as the electrolyte. It must first be charged by passing an electric current through it for a number of hours. Lead oxid collects on one plate and spongy lead on the other. It can then be used at any time to give a current of 2+ volts until the stored electricity is all given off, when it must be charged again.