(1) Positive electrode plate (positive electrode active material)
The main component of the active material of the positive electrode plate is lead dioxide. It has strong oxidizing property. When it is discharged, it reacts with sulfuric acid to form lead sulfate and absorbs electrons. There are two types of crystal lattice of lead dioxide, one is α-Pb02. The other is β-Pb02. These two kinds of lead dioxide active substances are very different, and their roles in the positive electrode plate are also different. The capacity given by ß-Pb02 is 1.5~~~3 times that of α-PbO2. While α-Pb02 has good mechanical strength, its existence, the active material of the positive electrode plate should not soften and fall off. Only when the ratio of α-Pb02 and βα-PbO2 reaches 0.8, the lead storage battery will show good performance.
The positive active material reacts with electrolyte sulfuric acid to form lead sulfate and water under discharge state. The reaction formula is as follows: Pb02+3H++HSO4+2e==PbSO4+2H2O When charged, it is converted into ÏbO2 and H2SO4 under the action of external circuit. During discharge, Ïb4+ of lead dioxide accepts electrons from the negative electrode to form Ïb+2 and combines with sulfate ions in solution to form ÏbSO4. When lead sulfate reaches a certain amount, it becomes a precipitate attached to the plate. The electrons of lead ions in lead sulfate are converted into lead dioxide by the external circuit. The hydrogen ions in the water are left in the solution. The oxygen ions combine with lead ions to form lead dioxide into the crystal lattice to form the positive active material.
(2) Negative electrode plate (negative electrode active material)
In the lead-acid battery, in order to fully react the negative active material with the electrolyte, lead is made into a porous sponge, also known as sponge lead. When discharging, lead gives external line electrons to form Pb+2 and solution. Sulfate is combined to form lead sulfate. When charging, part of PbSO4 is first dissolved into Pb2+ and SO4. Pb+2 accepts electron reduction to lead into the negative active material lattice.
(3) Electrolyte
Sulfuric acid is one of the important raw materials in the electrolyte of lead-acid batteries. There are two kinds of concentrated sulfuric acid on the market: one is industrial concentrated sulfuric acid, the purity is low, it is not suitable for lead-acid batteries; the other is higher purity. The analytical grade is more suitable for lead-acid batteries. The molecular weight of sulfuric acid is 98, and the sulfuric acid content of concentrated sulfuric acid is 98%. It is a colorless transparent oily liquid. It has strong water absorption and corrosivity. When combined with water, it can release a large amount. The heat. Therefore, in the electrolyte preparation process, we must pay attention to protection, so as to avoid danger. When preparing, do not add water to concentrated sulfuric acid, but slowly add concentrated sulfuric acid to the water. In the preparation process of lead-acid battery electrolyte, the requirement for water is high, and the amount of impurities in water directly affects the quality of the battery. The appearance of lead battery is colorless and transparent, and the residue content should be less than 0.01%. The standard for general inspection water It is expressed by resistivity (Ωcm) or conductivity. The simpler method is to use resistivity measurement method: use a digital multimeter to set the gear position to 20MΩ, and measure the resistance of the water by connecting the two test leads of the multimeter by 1 cm. The resistance is 5 - 10MΩ.
(iv) Partition
The separator is also one of the main components of the lead storage battery. Its quality has a great influence on the battery. The main function of the separator is to prevent short circuit between the positive and negative electrodes of the battery. In the battery, the requirement for the separator is: using a porous separator, allowing The free diffusion and ion migration of the electrolyte should have a relatively small resistance, and the pore size of the separator should be small. The total area of ​​the void should be large, and the active material that has fallen off should be prevented from reaching the opposite plate. Therefore, the pore size of the separator should be small, and the number of pores should be small. need more.
.
Replacement Transfer Case,Hydraulic Motor For Danfoss,Orbital Hydraulic Motor,Small Loaders Hydraulic
Jinan Voton Machinery Equipment Co., Ltd , https://www.votonmachinery.com