When a car battery is discharged, the sulfuric acid reacts with the lead plates in the battery to produce lead sulfate and water. This reaction causes the lead plates to become less dense and the electrolyte to become more dense. When the battery is recharged, the reverse reaction occurs and the lead sulfate is converted back into lead and sulfuric acid.
The concentration of sulfuric acid in the electrolyte is important because it affects the battery's performance. If the concentration is too low, the battery will not be able to produce enough power. If the concentration is too high, the battery will be more likely to overheat and fail.
The level of the electrolyte in the battery is also important. If the level is too low, the plates will be exposed to air and will corrode. If the level is too high, the battery will be more likely to leak.
