News

In the modern logistics and warehousing industry, forklifts, as core handling equipment, have a direct impact on the production efficiency of enterprises due to their efficient and stable operation. As the power source of electric forklifts, the performance of lead-acid batteries is even more crucial. In the composition structure of lead-acid batteries, the electrolyte plays an indispensable role. Its performance not only directly affects the charging and discharging efficiency and service life of the battery, but also influences the overall operational stability and safety of the forklift. A thorough understanding of the role of the electrolyte in forklift lead-acid batteries and proper maintenance have become important issues for ensuring the normal operation of forklifts.

1. Composition and Properties of Electrolyte in Forklift Lead-Acid Batteries

The electrolyte of forklift lead-acid batteries is mainly composed of sulfuric acid and distilled water mixed in a certain proportion. Sulfuric acid, as a strong electrolyte, can completely ionize in aqueous solution, generating hydrogen ions and sulfate ions. These ions are the key for the electrolyte to achieve its conductive function. The density of the electrolyte is usually between 1.28 and 1.30g/cm³. This density range has been determined through long-term practice and research, which can ensure that the battery operates in the best condition. The density of the electrolyte changes with temperature, generally following the principle of thermal expansion and contraction. When the temperature rises, the density decreases; when the temperature drops, the density increases. Meanwhile, the electrolyte is highly corrosive. Sulfuric acid is chemically active and can undergo chemical reactions with many metals. Therefore, protective measures must be taken during operation to avoid contact with skin and clothing.

2. The Core Role of Electrolyte in Lead-Acid Batteries

(1) Conductive effect

During the charging and discharging process of lead-acid batteries, the electrolyte acts as an ionic conductor. When the battery is charging, the external power source forces electrons to flow out from the negative terminal of the battery, through the external circuit to the positive terminal. Inside the battery, ions in the electrolyte move directionally, forming a current loop. Specifically, the lead on the negative plate loses electrons during the charging process, generating a lead-ion electrolyte that combines with sulfate ions in the electrolyte to form lead sulfate, which adheres to the negative plate. Meanwhile, lead dioxide on the positive plate, after gaining electrons, reacts with hydrogen ions and sulfate ions in the electrolyte to form lead sulfate and water. The discharge process is the reverse reaction of the charging process. Ions in the electrolyte move, converting lead sulfate on the positive and negative plates into lead and lead dioxide respectively, while releasing electrical energy. It can be seen from this that the good conductivity of the electrolyte is the basis for lead-acid batteries to achieve the mutual conversion of electrical energy and chemical energy. If the conductivity of the electrolyte deteriorates, it will lead to a significant reduction in the charging and discharging efficiency of the battery.

(2) Participate in electrochemical reactions

The electrolyte is not only a conductive medium but also directly participates in the electrochemical reactions of lead-acid batteries. During the charging process, sulfuric acid undergoes a chemical reaction with the active substances on the positive and negative plates, converting electrical energy into chemical energy for storage. At the negative electrode, sulfuric acid reacts with lead to form lead sulfate and electrons. At the positive electrode, sulfuric acid reacts with lead dioxide, consuming water while generating lead sulfate. During discharge, these chemical reactions proceed in reverse, converting the stored chemical energy into electrical energy and releasing it. The concentration and content of sulfuric acid in the electrolyte will affect the speed and depth of the electrochemical reaction. An appropriate concentration of sulfuric acid can ensure that the electrochemical reaction proceeds fully, thereby enhancing the charging and discharging capacity and efficiency of the battery.

(3) Heat dissipation effect

Lead-acid batteries generate a certain amount of heat during charging and discharging, especially when charging and discharging with high current or working continuously for a long time, the accumulation of heat is more obvious. Due to its large specific heat capacity, the electrolyte can absorb the heat generated inside the battery and dissipate the heat to the surrounding environment through heat conduction and convection, thereby playing a role in regulating the battery temperature. A stable temperature environment helps maintain the stability of the chemical reactions inside the battery, preventing the deformation of the battery plates and the shedding of active substances due to excessively high temperatures, and thus extending the battery's service life. If the amount of electrolyte is insufficient, its heat dissipation capacity will decline, the battery temperature will rise, and it will accelerate the aging and damage of the battery.

3. Key Points for Maintaining the Electrolyte of Forklift Lead-Acid Batteries

(1) Regularly check the electrolyte level

The electrolyte level is one of the key indicators that need to be focused on during daily maintenance. As the battery undergoes charge and discharge cycles, the water in the electrolyte is constantly consumed, causing the liquid level to drop. When the liquid level is too low, the plates will be exposed to the air. On the one hand, this will cause the plates to oxidize, reduce their activity, and affect the charging and discharging performance of the battery. On the other hand, exposed plates are more prone to heat up during the charging process, accelerating their damage. Therefore, it is necessary to check the electrolyte level regularly. Generally, it is recommended to do so once a week. When conducting the inspection, you can use a transparent plastic straw or a dedicated liquid level detection tool. Insert it into the battery and observe whether the liquid level is between the upper and lower limit marks. Under normal circumstances, the electrolyte level should be 10 to 15mm higher than the top of the plates. If the liquid level is lower than the lower limit, distilled water or special lead-acid battery replenishment fluid should be added in time. It should be noted that the addition of sulfuric acid or other liquids containing impurities is strictly prohibited to avoid affecting the composition and performance of the electrolyte.

(2) Monitor the density of the electrolyte

The density of the electrolyte is an important parameter reflecting the charging and discharging state of the battery and the concentration of the electrolyte. By regularly measuring the density of the electrolyte, one can understand the charging and discharging level of the battery and determine whether the electrolyte needs to be adjusted. Generally, a hydrometer is used to measure the density of the electrolyte. When measuring, the battery should be fully charged and left to stand for 1 to 2 hours until the temperature of the electrolyte stabilizes. The standard density of the electrolyte of lead-acid batteries of different models and specifications varies slightly. However, generally, when fully charged, the density should be between 1.28 and 1.30g/cm³, and it will decrease after discharge. If the density of the electrolyte is found to deviate from the standard range, adjustments should be made according to the specific circumstances. If the density is too high, it might be due to excessive evaporation of water in the electrolyte. Distilled water can be added appropriately for dilution. If the density is too low, it may be due to over-discharge of the battery or insufficient sulfuric acid content in the electrolyte. The battery needs to be recharged and checked for problems such as electrolyte leakage.

(3) Prevent contamination of the electrolyte

Once the electrolyte is contaminated, it will seriously affect the performance and service life of the battery. During daily maintenance and use, it is necessary to pay attention to preventing impurities from entering the battery interior. For instance, when adding distilled water or supplementary liquid, the tools used must be kept clean to prevent impurities such as dust and metal shavings from being brought into the battery. The surface of the battery should be kept clean and dry. Any spilled electrolyte and dust should be cleaned up in time to prevent the mixture of electrolyte and dust from entering the battery through the vent holes on the battery cover. In addition, during operation, forklifts should avoid running for long periods in environments with large amounts of dust and corrosive gases to prevent external contaminants from entering the battery and affecting the quality of the electrolyte.

(4) Control the charging process

A reasonable charging process is crucial for the maintenance of the electrolyte. Overcharging or excessive charging current will cause a large amount of water in the electrolyte to decompose, generating hydrogen and oxygen, resulting in a rapid drop in the electrolyte level. At the same time, it will also cause severe battery heating and accelerate the aging of the plates. Therefore, a charger that matches the battery specifications should be used and the charging operation should be carried out strictly in accordance with the charger's instructions. During the charging process, pay close attention to the battery temperature and charging current. When the battery temperature exceeds 45℃, charging should be suspended and resumed only after the temperature drops. In addition, to prevent excessive battery discharge, when the forklift's battery power remains at 20% to 30%, it should be charged in a timely manner to avoid sulfation of the plates due to excessive discharge, which may affect the normal operation of the electrolyte.

(5) Responding to extreme environments

The performance of the electrolyte in forklifts will be affected to a certain extent when they operate under different environmental conditions. In high-temperature environments, the evaporation rate of water in the electrolyte increases, the liquid level drops significantly, and at the same time, the chemical reaction rate inside the battery speeds up, making it easier to generate heat and accelerating the aging of the battery. At this point, the frequency of checking the electrolyte level should be increased, distilled water should be replenished in a timely manner, and appropriate cooling measures should be taken, such as installing a heat dissipation device on the battery or avoiding continuous use of the forklift for a long time during high-temperature periods. In a low-temperature environment, the density of the electrolyte increases, its fluidity deteriorates, the electrochemical reaction rate slows down, and both the charging and discharging capacity and efficiency of the battery will decrease. To ensure the normal operation of the battery, the density of the electrolyte can be appropriately increased before winter arrives. Generally, the density can be raised by 0.02-0.03g/cm³. At the same time, try to store the forklift in a warm indoor area or wrap the battery with insulation materials to prevent it from cracking due to freezing.

4. Hazards of Improper Maintenance of Electrolyte and Solutions

(1) Plate vulcanization

If the electrolyte level is too low, the plates are exposed to the air for a long time, or the battery is often in an overdischarged state, a layer of white and hard lead sulfate crystals will gradually form on the surface of the plates, which is known as plate sulfation. Sulfation of the plates will lead to a reduction in the active material of the plates, an increase in the internal resistance of the battery, a decline in charging and discharging performance, and in severe cases, it will cause the battery to fail to work normally. Once sulfation of the plates is detected, it can be repaired by charging with a small current for a long time or using a sulfation removal charging device. However, the problem of plate sulfation should be prevented mainly by regularly checking the electrolyte level and avoiding excessive discharge.

(2) The battery is overheating severely

Insufficient electrolyte volume or abnormal density will lead to a decline in the battery's heat dissipation capacity, resulting in severe heat generation during charging and discharging. Long-term high temperatures can cause the plates to deform and the active substances to fall off, shortening the service life of the battery. When the battery is found to be overheating, the forklift should be stopped immediately. Check the electrolyte level and density, add an appropriate amount of distilled water or adjust the electrolyte density, and ensure good ventilation of the battery. If the heating problem persists, a comprehensive inspection and repair of the battery should be carried out in a timely manner.

(3) Electrolyte leakage

Electrolyte leakage not only pollutes the environment but also leads to insufficient electrolyte inside the battery, affecting its performance. Electrolyte leakage may be caused by reasons such as damaged battery casing, poor sealing or excessive gas pressure generated during charging. Once electrolyte leakage is detected, immediate protective measures should be taken. Special tools and containers should be used to collect the leaked electrolyte, and the leakage area should be cleaned and neutralized to prevent the electrolyte from corroding equipment and the ground. At the same time, inspect the battery, repair or replace damaged parts, and ensure that the battery is well sealed.

5. Future Development Trends

With the continuous advancement of technology, the related technologies of lead-acid battery electrolyte for forklifts are also constantly developing. On the one hand, the research and development of new electrolyte additives has become a hot topic. By adding special chemical substances, the conductivity of the electrolyte can be improved, the sulfation of the plates can be inhibited, and the service life of the battery can be prolonged. On the other hand, intelligent electrolyte monitoring systems are gradually being applied in the forklift field. By using sensors to monitor parameters such as the liquid level, density and temperature of the electrolyte in real time, and transmitting the data to the forklift's control system or remote monitoring platform, real-time early warning and intelligent management of the electrolyte status can be achieved, improving the accuracy and efficiency of electrolyte maintenance. In addition, research on environmentally friendly electrolytes is also being actively advanced, aiming to reduce the pollution of electrolytes to the environment and meet increasingly strict environmental protection requirements.

In conclusion, the electrolyte of forklift lead-acid batteries plays a crucial role in the operation of the battery, including conducting electricity, participating in electrochemical reactions, and dissipating heat. Proper maintenance of the electrolyte, including regular checks of the liquid level and density, prevention of contamination, control of the charging process, and response to extreme environments, is the key to ensuring the performance of lead-acid batteries and extending their service life. At the same time, understanding the possible hazards caused by improper maintenance of the electrolyte and taking timely solutions are of great significance for ensuring the normal operation of forklifts and the production efficiency of enterprises. With the continuous development of technology, the maintenance of lead-acid battery electrolyte in forklifts will become more intelligent and environmentally friendly, providing more reliable power support for the development of the logistics industry.