types of Batteries

TYPES OF BATTERIES The lead-acid battery is the most common type of battery in use today.  There are other types of storage batteries, each having certain advantages. EO 1.9 STATE  the  advantage  of  each  of  the  following types of batteries: a. Carbon-zinc cell b. Alkaline cell c. Nickel-cadmium cell d. Edison cell e. Mercury cell Wet and Dry Cells Wet and dry cells are classified by the type of electrolyte the battery uses.   The electrolyte of a cell may be a liquid or a paste.   If the electrolyte is a paste, the cell is referred to as a dry cell. If the electrolyte is a solution, the cell is called a wet cell. Carbon-Zinc Cell The carbon-zinc cell is one of the oldest and most widely used types of dry cells.   The carbon in the battery is in the form of a rod in the center of the cell which acts as the positive terminal. The case is made from zinc and acts as the negative electrode.   The electrolyte for this type of cell is a chemical paste-like mixture which is housed between the carbon electrode and the zinc case.   The cell is then sealed to prevent any of the liquid in the paste from evaporating. The advantage of a carbon-zinc battery is that it is durable and very inexpensive to produce.  The cell voltage for this type of cell is about 1.5 volts. Alkaline Cell The alkaline cell is so called because it has an alkaline electrolyte of potassium hydroxide.  The negative electrode is made from zinc, and the positive electrode is made of manganese dioxide. The typical alkaline cell generates 1.5 volts.  The alkaline cell has the advantage of an extended life over that of a carbon-zinc cell of the same size; however, it is usually more expensive. ES-04 Page 14 Rev. 0