A battery as we know it is a device that stores chemical energy and through an electrochemical process (electromotive force) converts the stored chemical energy into electric energy via a direct current voltage. The chemical conversion is a process of chemical change created by adding or losing chemical substances (electrons, oxygen, lithium etc.) inside the battery and used by a connecting device (i.e. PDA, iPod, Digital Camera).
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A battery is a device that converts chemical energy into electrical energy. Batteries have two electrodes, an anode (the positive end) and a cathode (the negative end). In between the battery’s two electrodes runs an electrical current caused primarily from a voltage differential between the anode and cathode. The voltage runs through a chemical called an electrolyte (which can be either liquid or solid). This battery consisting of two electrodes is called a voltaic cell.