When the battery is charged, lead and lead dioxide are formed at the two poles, respectively. When charging, electrical energy is converted into chemical energy, and when discharging, chemical energy is converted into electrical energy. Regarding the basic knowledge, purchase and maintenance of car batteries, it is enough to read an article. The structure of the battery is simple to protect the lead-acid battery: the lead-calcium alloy grid is used, and the amount of moisture that occurs during charging is low, and the amount of water evaporation is low.

In addition, the shell adopts a sealed structure, and the released sulfuric acid gas is also very small. Therefore, compared with ordinary batteries, it has the advantages of no need to add liquid, less corrosion to wiring piles and wires, strong resistance to overcharging, large starting current, and long storage time for electricity. The protection-free lead-acid battery is only slightly different from the general battery in structure, and the working principle is generally the same.

In general, lead-acid batteries are compared with unprotected lead-acid batteries. Another point to mention is that the protection-free battery is not absolute. Although it consumes less electrolyte, it also needs regular maintenance. This is explained in detail later in the article on battery maintenance. . The car battery functions and the car starts to supply power for the car's starting combustion system.

With the popularization of one-button start, car start-up relies more and more heavily on the battery. When the generator does not generate electricity or the electrical appliances in the car are overloaded, it supplies power to the car's electrical equipment, including car headlights, instrument panels, central control panels, Air conditioners, wipers, interior lights and cigarette lighters, etc.; the electronic equipment in the car needs to rely on the battery to supply power and store the excess power generated by the generator.