What is Lead Acid Battery
Lead Acid battery is a lead-acid battery, which is a battery in which the electrode is mainly made of lead and its oxide, and the electrolyte is sulfuric acid solution.
1.Structure and composition
Cathode: The main component is lead dioxide (PbO₂), which has high electrochemical activity, and realizes the transfer and storage of electrons through chemical reaction with sulfuric acid solution during charging and discharging.
Negative electrode: usually composed of spongy lead (Pb), this structure makes the lead have a large specific surface area, which can better react with the electrolyte, and in the process of charging and discharging, the negative lead loses or gains electrons, realizing the discharge and charging functions of the battery.
Electrolyte: Generally a sulfuric acid solution prepared from pure sulfuric acid (H₂SO₄) and distilled water in a certain proportion. It plays the role of ion conduction in the battery, so that a conductive path can be formed between the positive and negative electrodes, so as to realize the chemical reaction and charge transfer inside the battery.
Separator: Usually made of microporous rubber, microporous plastic and other materials, its function is to separate the positive and negative plates, prevent the positive and negative electrodes from direct contact and short circuit, and at the same time allow the ions in the electrolyte to pass freely to ensure the ion conduction inside the battery.
2.How it works
Discharge process: When the battery provides electrical energy to the external circuit, the lead (Pb) of the negative electrode reacts with the sulfate ion (SO₄²⁻) in the electrolyte to form lead sulfate (PbSO₄), and releases electrons, which flow to the positive electrode through the external circuit. On the cathode, lead dioxide (PbO₂) reacts with electrons and hydrogen ions (H⁺) under the action of sulfuric acid to form lead sulfate (PbSO₄) and water (H₂O).
Charging process: When the battery is connected to the charger, the electrical energy provided by the external power source causes the chemical reaction inside the battery to go in reverse. At the negative electrode, lead sulfate (PbSO₄) gets electrons and is reconverted to lead (Pb) and sulfate ions (SO₄²⁻); At the positive electrode, lead sulfate (PbSO₄) and water (H₂O) lose electrons to form lead dioxide (PbO₂), hydrogen ions (H⁺), and sulfate ions (SO₄²⁻).
3.Features
Mature technology: After years of development and research, the technology of lead-acid battery has been very mature, with stable production process and reliable performance, which can meet the needs of a variety of application scenarios.
Low cost: Compared with some other new batteries, the raw material cost of lead-acid batteries is relatively low, and the production equipment and process are relatively simple, so the price is relatively affordable and has a high cost performance.
Good high-current discharge performance: It can provide a large discharge current in a short time, and is suitable for some applications that require instantaneous high-current, such as car starting.
Low energy density: The amount of electrical energy stored per unit weight or unit volume is relatively small, which makes lead-acid batteries large in size and weight, and is not friendly to some application scenarios with high space and weight requirements.
Limited cycle life: In general, the cycle life of lead-acid batteries is about a few hundred times to a thousand times, and the performance of the battery will gradually decline as the number of charging and discharging times increases.
High maintenance requirements: During use, it is necessary to regularly check the level and density of the electrolyte, and replenish distilled water or electrolyte in time to ensure the normal operation of the battery.
4.Application
Automobile starting power supply: It provides instantaneous high current for the start of the automobile engine, and at the same time, provides power support for the vehicle’s electronic equipment such as radios and lights when the engine is not working.
Uninterruptible power supply (UPS): In the event of a power outage, it provides temporary power guarantee for important loads such as computers, communication equipment, and medical equipment to ensure the normal operation of equipment and prevent data loss and equipment damage.
Electric bicycle: As the power source of electric bicycles, it provides electrical energy for the motor of electric bicycles, drives vehicles to drive, and meets the needs of people for short-distance travel.
Solar and wind energy storage systems: In solar and wind power generation systems, it is used to store excess electrical energy to provide users with electricity at night or when there is no wind or sunlight, so as to achieve a stable supply of energy.