One reason for the ubiquity of these batteries in cars and all kinds of other automobiles is because when automobiles first came into being, the only viable option for batteries was the Lead Acid type. Secondly, when you consider the amount of charge one of these batteries can hold, it is incredibly cheaper than other types of batteries with similar capacity. The third reason is that it is possible to use this type of battery for five or ten years with proper maintenance. When you compare that to the three-year lifespan of Li-ion batteries, lead-acid batteries are extremely cost-effective.