The car battery, a common enough item and a piece of common technology. Arguably the battery is the heart of every car we see on the road today. If the car is not running or junked or would not start, chances are it has a dead battery. What is a car battery and what engineering methods are responsible for storing electricity inside a box? Let us take a closer look at this commonplace, but nevertheless an amazing and important piece of machinery.
The earliest form of a supposed battery was discovered in the 1930’s in Baghdad, Iraq. Although it has the basic parts of a battery, is exact purpose is unclear. The battery is from 250 BC and no discernible purpose for it is found in that era. However, for our purposes of exploring how batteries came to be, this would be considered as the earliest form of storing electricity known to man.
The first ever car battery, the lead-acid battery was invented in the 1800’s, this became the precursor for modern batteries.
Lead-acid batteries fall into the SLI category. SLI stands for “starting-lighting-ignition” which means that it not only powers the starter motor but ignition and lighting systems too. SLI batteries are made up of six galvanic cells laid out in a series. Each cell delivers 2.1 volts of electricity and when combined, produce a 12 volt SLI battery. The battery will have two terminals to connect them to the components of the car and is made of lead, a corrosion resistant material. Each galvanic cell consists of lead and lead dioxide plates which are submerged in an electrolytic solution which is, in turn, a mix of sulphuric acid and water. This acid “bath” triggers a reaction with the lead dioxide plate and produces ions and lead sulfate. These ions then react with the adjacent lead plates and to produce hydrogen ions and lead sulfate. This chemical reaction generates electrons that flow out of the terminals to power whatever electrical systems need power in the vehicle. This has been the basic flow of what goes on inside a battery even up to now. However modern systems have grown around the lead-acid batteries such as battery regulator, the maintenance-free gel battery, and solar applications. Some modern conveniences will also include battery charge controllers and chargers.
However the battery works, it remains a vital part of any electrical system. especially those that need storage and back up. Battery systems are essential not only to vehicles but other systems as well. In todays world some vehicles even run on battery power alone and points to the direction this technology is going.