Lead-acid Batteries are Rechargeable
A car battery is a rechargeable battery primarily used for starting, lighting, and ignition. Car batteries are normally 12-volt (12.6 volts at full operational capacity). This type of battery produces direct current (DC) electricity that flows in only one direction. When the battery is discharging (current flowing out of the battery), it changes chemical energy into electrical energy, thereby, releasing stored energy. During charging (current flowing into the battery from the charging system), electrical energy is converted into chemical energy. The battery can then store energy until the vehicle requires it.
Automotive batteries are usually lead-acid types consisting of a series of six galvanic cells. Lead-acid batteries consist of plates of lead and lead oxide which are submerged in an electrolyte solution consisting of sulfuric acid and water. The lead and lead oxide chemically react with the electrolyte solution to produce electrons which flow through conductors and produce electricity. When this chemical process is reversed, the battery is recharged by your vehicles alternator.