Lead and Acid

• Car batteries are made with lead and lead oxide plates. These plates are placed next to each other in a mixture of water and sulfuric acid. The solution is about one-third acid and two-thirds water; the addition of the acid makes it an electrolytic substance, which means electrolytes pass through it.
  
  

Construction

• The lead plates and lead oxide plates are attached to a rack that has electrical connections that can transfer a charge. The base of the battery is made from simple plastic, formed in a mold by injection molding. The base is filled with the acid and water solution, then the plate assembly is placed inside and secured to the base plastic.
  
  

Terminal Assembly

• The terminal includes the positive and negative charge heads. The terminal is prewired to accept the charge that will occur once the plates are set into the acid solution. There is an electrical assembly that is placed into the terminal box that transfers the charge to the battery terminals. The positive is wired to the end of the plate assembly so the electrons can flow from the plates into the terminal. Once charged, electrons will begin to flow from one plate to another. Each plate is responsible for part of the total 12-volt charge. In a six-cell battery (six plates of each lead type), each one accounts for about 2.1 volts. So, each plate is prewired to relay its voltage to the positive terminal. The ground is wired back to the other end of the assembly.