Failure modes of valve-regulated lead-acid batteries

Failure mode of valve-regulated lead-acid battery

The performance deterioration mechanism of valve-regulated lead-acid battery is affected by the following conditions:

1. Heat accumulation

In addition to the remanufacturing of active materials, the water in the hydrochloric acid electrolyte is also converted into radon and carbon dioxide. When 8 grams of water is dissolved, when the rechargeable battery cover discharges gas into the air, it will cause calories of heat.

In the case of valve-regulated lead-acid batteries, the flow of carbon dioxide inside the battery is negative. Carbon dioxide oxidizes the active material in the negative plate and fills the water lost by electrolysis. Because the oxygen cycle prevents radon from dissolving, CO2 is reflected and converted into water. In this way, although it is difficult to remove flammable vapor compounds, this closed form is an effective way to reduce heat diffusion, and only based on the heat conduction of the rechargeable battery case wall as a heating method.

Therefore, the inability to control the heat of valve-regulated lead-acid batteries has become a common problem.

Valve-regulated lead-acid batteries rely on the heat conduction of the shell wall to heat the heat pipe. Rechargeable batteries have good natural ventilation performance, and low indoor temperature is an important criterion. In order to further reduce the risk factors that cannot be controlled by heat, the floating operating voltage generally depends on different operators and different indoor temperatures. The manufacturer usually obtains the load voltage and temperature compensation index of the rechargeable battery.

2. Sulfation

The problem of valve-controlled batteries is the sulfation of the negative plate. It is because

(1) The oxygen circulation system causes the negative plate potential difference to be small;

(2) In this non-liquid, non-circulating system, strong alkaline electrolysis cannot be prevented The level of acid produced by the accumulation of liquid at the bottom of the rechargeable battery.

Both will produce a certain amount of potassium thiocyanate under the flotation standard, and then convert it into potassium thiocyanate. Therefore, when the plate accelerates the removal activity, the charge and discharge can be reduced. As the negative polarity increases, this situation will get worse. Due to the oxygen circulation system, the surface layer of the negative plate is oxidized, and the total heat is released.

3. Corrosion and shedding of the positive plate group

In valve-regulated lead-acid batteries, the characteristics of this method are more severely affected by the original. Because the oxygen circulation system reflects that the negative electrode active material is oxidized to lead sulfate by continuous air, and the charge and discharge conditions are reasonably maintained, the potential difference of the negative plate is reduced. The floating operating voltage is relatively high, and the potential difference is relatively large. Therefore, the air oxidation atmosphere is intensified, leading to the dissolution of a large amount of CO2, which intensifies the erosion and decline of active materials.

4. Drying of the battery

During the construction period, the efficiency of the steam reforming system is not higher than 100%, and the rate of the electrolysis method to convert water into radon gas and carbon dioxide is less than that of the same size. 2% of the electrolysis rate of the liquid battery.

When lack of water is the key cause of failure, the proportion of electrolyte solution may increase. When the proportion increases from the beginning, the expression of lack of water is about 25%. When the water shortage rate is 25%, the acid concentration accelerates the hydrochloric acid, and the electrolyte ratio has just begun to decline. The battery voltage is proportional to the electrolyte ratio, so the battery voltage is not a reliable indicator of battery health.

5. Corrosion of lead on the upper part of the negative electrode

In every design of lead-acid batteries, corrosion of grids and cathode clusters is expected to occur. In contrast, the negative plate is located in the high-aspect ratio recycled atmosphere, while in the open-end rechargeable battery, it is generally immersed in the liquid level of the lithium battery electrolyte to prevent the corrosion of the positive electrode group by CO2. However, many valve-regulated rechargeable battery design solutions do not maintain electrode plate ears, electrode groups and medical flux, which are very mutual welds. As a result, they are affected by the continuous carbon dioxide cyclone on the oxygen cycle and on the solar panel. Rapid air oxidation will occur, depending on the consistency of the mesh (plate lugs) and the choice of aluminum alloy and production quality (low porosity of the welding and medical flow discharge must be melted in the partial mesh).