The task of this paper is to classify chemical sources of electrical energy and briefly describe the basic characteristics of primary and secondary chemical sources of electrical energy. The introductory chapter defines the meaning of a battery as a chemical source of electrical energy, the difference between a battery and a cell, and a wide range of applications for the same. The second chapter provides a description, the history of the creation of a battery, and a general division into primary and secondary chemical sources of electrical energy. It also defines the concepts of electrode potential and electrical polarization. The third chapter classifies and describes primary chemical sources of electrical energy, starting from the oldest and technologically simplest cells (Voltaic, Weston’s), all the way to the technologically more modern mercury, alkaline, and silver batteries. The fourth chapter provides a division, description, and application of secondary chemical sources of electrical energy, as another large and important group of chemical sources, which today have a very wide range of applications. The final fifth chapter provides insight into some more modern technologies, which are increasingly being researched and advanced, as possible successors to current sources. A brief description of future technologies such as supercapacitors, fuel cells, and nuclear batteries is presented.