jalen said:A typical automoblie engine uses a lead-acid battery. During discharge, the following chemical reaction takes place.
Pb (s) +PbO2 (s) +2H2SO4 (aq) +2H2O2 (l)
(1) Pb (s) +PbO2 (s) +2SO3 (g) ---> 2PbSO4 (s) H= -775KJ
(2) SO3 (g) + H2O2 (l) ---> H2SO4 (aq) H= -133KJ
A lead-acid battery works by converting chemical energy into electrical energy through a series of chemical reactions. Inside the battery, there are two lead plates, one coated in lead dioxide and the other in metallic lead, submerged in an electrolyte solution of sulfuric acid. When the battery is connected to a circuit, the chemical reactions between the plates and the electrolyte create an electrical current.
The main components of a lead-acid battery are the lead plates, sulfuric acid electrolyte, and the casing. The lead plates are the electrodes that undergo the chemical reactions to produce electricity. The electrolyte is a solution of sulfuric acid that allows the flow of ions between the plates. The casing is usually made of plastic and holds all the components together.
In a lead-acid battery, the chemical reactions occur between the lead plates and the sulfuric acid electrolyte. The lead plate coated in lead dioxide (PbO2) undergoes oxidation, releasing electrons and forming lead sulfate (PbSO4). At the same time, the metallic lead (Pb) plate undergoes reduction, accepting the released electrons and forming lead sulfate (PbSO4). These reactions produce an overall flow of electrons, creating an electrical current.
Temperature can affect the chemical reactions in a lead-acid battery in several ways. Higher temperatures can increase the rate of the reactions, leading to a higher discharge rate. However, extreme temperatures, both hot and cold, can damage the battery and decrease its lifespan. Cold temperatures can also slow down the chemical reactions, reducing the battery's performance.
Lead-acid batteries are commonly used in automobiles because they are relatively inexpensive, have a high energy density, and can provide high bursts of power. They are also easy to manufacture and can be recharged multiple times, making them a cost-effective option for powering vehicles. Additionally, lead-acid batteries are recyclable, making them a more environmentally friendly choice compared to other battery types.