Lead-acid battery work principle
Number of views：18344 Time：2018-03-15
1, battery discharge
When the load on the battery and the circuit is turned on, under the action of the electric potential, the current flows from the positive electrode to the negative electrode (electrons flows from the battery negative electrode to the positive electrode), so that the positive electrode potential is lowered, the negative electrode potential is elevated, and the original Some balance. The chemical reaction process during discharge.
The reaction on the positive plate is as follows:
At the negative plate, the Pb atom lost electrons into PB2 ', and the SO in the electrolyte also generated PBS (). Sand on the negative electrode plate, and the metal on the plate continues to dissolve, and PBZ 'and electrons are generated.
The reaction on the negative plate is as follows:
PB SO4 2e → PBS04
If the circuit is not interrupted, the chemical reaction will continue to be carried out, making the PB on the PB02 on the positive electrode plate and the PB on the negative electrode plate gradually transformed into. PBS04, the H2S04 in the electrolyte gradually decreases and the water is gradually increased, and the relative density of the electrolyte is reduced. The total chemical reaction is as follows:
2, charging of the battery
When charging, the positive and negative electrode of the battery is connected to the positive and negative electrode of the DC power source, when the power supply voltage is higher than the electric power of the battery, the current flows from the battery positive from the battery, and the power is driven from the battery. The positive electrode is flowed to the negative electrode).
The reaction on the positive plate is as follows:
PBS04 40T {_ a 2e_ ÷ PB02 2H20 S0:
At the negative plate, there is a small amount of PBSO. In the electrolyte, the dissociation is. PB: 'and S00 PB. The two electrons becomes metal Pb under the action of the power supply, and is attached to the negative plate. SO} is bonded to H in the electrolyte to form sulfuric acid.
The reaction on the negative plate is as follows:
It can be seen that the PBSO on the positive and negative plate during the charging process. It will gradually return to PB and Pb, and H2S0 in the electrolyte. Gradually increase and water gradually decrease, the relative density of the electrolyte increases. The total chemical reaction is as follows:
The chemical reaction process at the time of charge and discharge of the battery can be drawn.
(1) When the battery is discharged, the sulfuric acid in the electrolyte gradually decreases, and the water is gradually increased, and the electrolytic solution is reduced; when the battery is charged, the sulfuric acid in the electrolyte gradually increases, and the water gradually decreases, and the electrolyte density is increased. Therefore, the extent of the battery charge and discharge is determined by measuring the electrolyte density.
(2) When charging and discharging, the electrolyte density changes, mainly due to the results of chemical reactions due to the active substance of the positive electrode, so that the electrolyte fluidity at the positive electrode plate is good. Therefore, when assembling the battery, the chip has a trench on the positive plate so that the electrolyte flows.
(3) When the battery discharge is finally, there is no role in the plates of '70% to 80% of the active substances. Therefore, to alleviate the quality of the lead battery, improve the power supply capacity, and should sufficiently increase the utilization of the plate active substance, and the porous properties of the plate can be improved, and the thickness of the plate is reduced.
