News

In the modern logistics and warehousing industry, forklifts, as indispensable handling equipment, the performance and stability of their power source - lead-acid batteries - directly affect the efficiency and safety of the entire operation process. Once a lead-acid battery malfunctions, it will not only cause the forklift to stop working and affect the turnover of goods, but also may result in huge economic losses due to delayed maintenance. Therefore, establishing a scientific and systematic daily inspection checklist and strictly implementing it is the key to preventing faults in forklift lead-acid batteries. This article will elaborate in detail on the essential steps for the daily inspection of lead-acid batteries in forklifts, providing practical references for equipment maintenance personnel and forklift operators.

1. Visual Inspection: The first step to identifying potential hazards

1.1 Shell integrity inspection

The casing of a lead-acid battery serves as an important barrier to protect the internal plates and electrolyte. During daily inspections, the first step is to carefully check whether the shell has any cracks, damages or deformations. Minor cracks may cause electrolyte leakage, which not only corrodes the forklift chassis and surrounding equipment, but also pollutes the working environment. More seriously, it can lead to a reduction in the electrolyte inside the battery, affecting battery performance. When inspecting, you can use a flashlight to illuminate all parts of the battery casing, including the bottom and sides, to ensure there are no tiny cracks that are hard to detect with the naked eye. Once the casing is found to be damaged, the battery should be stopped from use immediately and a professional should be contacted for replacement. Do not continue to use it with a  mentality.

1.2 Check the status of the terminal posts

The terminal post is a key component connecting the battery to the forklift circuit, and its condition directly affects the transmission of current. When inspecting the terminals, observe whether there is any corrosion, loosening or deformation on the terminals. Terminal post corrosion is usually manifested as the appearance of white or green powder-like substances on the surface, which is caused by the chemical reaction between the electrolyte leakage and substances in the air. Corroded terminals will increase contact resistance, leading to problems such as difficult startup and voltage drop. For minor corrosion, sandpaper or a special pole cleaning tool can be used for grinding, and then a layer of Vaseline or a special anti-corrosion grease can be applied to prevent further corrosion. If the corrosion is severe or the terminals are loose or deformed, new terminals or the entire battery need to be replaced. In addition, it is necessary to check whether the fixing bolts between the terminal post and the connecting wire are tightened to ensure a firm connection and avoid safety accidents caused by sparks due to loosening.

1.3 Inspection of exhaust holes

During the charging and discharging process of lead-acid batteries, gases such as hydrogen and oxygen are produced. The function of the exhaust hole is to promptly expel these gases to prevent the battery from exploding due to excessive internal pressure. When inspecting, make sure the exhaust holes are unobstructed and not blocked by dust or debris. You can use a thin wire or a special unclogging tool to gently insert into the exhaust hole for cleaning, but be careful not to damage the internal structure of the exhaust hole. At the same time, it is necessary to check whether the sealing cover of the exhaust hole is intact. If the sealing cover is damaged or lost, it should be replaced in time to prevent the electrolyte from splashing out and external impurities from entering the battery interior.

2. Electrolyte Inspection: The Key to maintaining battery performance

2.1 Liquid Level Check

Electrolyte is an important medium for electrochemical reactions in lead-acid batteries, and its liquid level height has a crucial impact on battery performance. Under normal circumstances, the electrolyte level should be 10 to 15 millimeters higher than that of the plates. If the liquid level is too low, the plates will be exposed to the air, causing sulfation of the plates and reducing the battery capacity and service life. If the liquid level is too high, it is prone to overflow during the battery charging and discharging process, corroding the battery casing and forklift components. When checking the electrolyte level, a transparent plastic pipette or a dedicated liquid level measuring tool can be used. Insert the straw into the exhaust hole until it touches the top of the plate, then block the upper end of the straw with your finger, take out the straw and observe the height of the electrolyte in the straw. If the liquid level is too low, distilled water or special lead-acid battery replenishment fluid should be added. Do not add tap water or other unknown liquids, as impurities in tap water may affect the chemical reaction of the battery. If the liquid level is too high, the excess electrolyte needs to be sucked out with a pipette.

2.2 Electrolyte density check

The density of the electrolyte reflects the charging and discharging state of the battery and the concentration of the electrolyte. The standard value of electrolyte density varies in different seasons and under different usage conditions. Generally speaking, at 25℃, the density of the electrolyte in a fully charged lead-acid battery is approximately 1.28g/cm³. As the battery discharges, the density will gradually decrease. When checking the density of the electrolyte, a dedicated hydrometer should be used. Insert the rubber tube of the hydrometer into the vent hole, draw in an appropriate amount of electrolyte, and make the float of the hydrometer float up. Read the scale value on the float that is level with the liquid surface, which is the density of the electrolyte. By regularly measuring the density of the electrolyte, one can understand the charging and discharging conditions of the battery, adjust the charging time and current in a timely manner, and avoid damage to the battery caused by excessive discharge and insufficient charging. If abnormal density of the electrolyte is found, such as a significant deviation from the standard value, it may indicate an internal fault in the battery. Further inspection or contact with professionals for handling is necessary.

2.3 Check the color and odor of the electrolyte

Under normal circumstances, the electrolyte should be colorless or light yellow and have no pungent smell. If the color of the electrolyte darkens, such as turning brown or black, or becomes cloudy, it indicates that severe sulfation, oxidation or other faults may have occurred on the internal plates of the battery. In addition, if the electrolyte emits a strong pungent smell, it might be due to overcharging the battery, causing the electrolyte to decompose and generating excessive acidic gas. Once any abnormal color or odor of the electrolyte is detected, the battery should be immediately stopped from use and a comprehensive inspection and repair should be carried out to prevent the fault from further expanding.

3. Charging System Inspection: The foundation for ensuring battery life

3.1 Charger Inspection

A charger is a device that replenishes electrical energy for lead-acid batteries, and its performance directly affects the charging effect and service life of the batteries. During routine inspections, it is necessary to check whether the appearance of the charger is intact, and whether there are any signs of damage, deformation or charring. Check whether the connection wires of the charger are damaged or aged, especially at the plug and socket parts. Make sure the connection is firm and there is no loosening or poor contact. In addition, it is necessary to check whether the indicator light of the charger is working properly. During the charging process, the indicator light should turn on and off according to the prescribed procedure. If the indicator light flashes abnormally or does not light up, it may be that the charger is faulty. In this case, stop using it and have it inspected and repaired. At the same time, it is necessary to clean the dust and debris on the surface of the charger regularly to prevent dust from entering the charger and affecting its heat dissipation and normal operation.

3.2 Check the charging voltage and current

During the charging process, the stability of charging voltage and current is of vital importance to the battery. Excessively high charging voltage and current can cause the battery to overheat, decompose the electrolyte, and accelerate battery aging. If it is too low, it will cause insufficient battery charging and affect the battery capacity. Use a multimeter or a dedicated voltage and current tester to measure the voltage and current values output by the charger during the charging process and compare them with the nominal parameters of the battery and the charger. Generally speaking, the charging voltage should be slightly higher than the rated voltage of the battery, and the charging current should be reasonably adjusted according to the battery capacity and the charging stage. In the later stage of charging, the charging current should be gradually reduced to switch to trickle charging to ensure that the battery is fully charged without being damaged. If abnormal charging voltage and current are found, the Settings of the charger should be adjusted in time or the charger should be inspected and repaired.

3.3 Charging time check

Reasonable charging time helps to extend the battery's service life. The charging time of lead-acid batteries of different capacities and specifications also varies. Generally speaking, the initial charging time of a new battery is relatively long, reaching 12 to 20 hours. The charging time after normal use depends on the degree of discharge, usually ranging from 6 to 10 hours. In daily use, record the time of each charge and adjust it according to the battery's usage. If you find that the charging time is significantly shortened or prolonged, it might be due to a decrease in battery capacity or a charger malfunction. Further checks on the performance of the battery and the charger are necessary. At the same time, overcharging and overdischarging should be avoided. Overcharging will cause the battery to heat up and accelerate its aging. Over-discharge will lead to sulfation of the plates and reduce the battery capacity. Therefore, the battery should be charged in time when the remaining power is 20% to 30%, and the charging should be stopped immediately after it is fully charged.

4. Temperature Check: Prevent Battery "heatstroke" and "frostbite"

The performance of lead-acid batteries is greatly affected by temperature. Both excessively high and low temperatures can cause damage to the batteries. During daily inspections, pay attention to the temperature of the battery surface and the working environment temperature. Under normal circumstances, batteries will generate some heat during charging and discharging, but the temperature should not be too high. If the surface temperature of the battery exceeds 50℃, it indicates that the battery may have problems such as overcharging, internal short circuit or poor heat dissipation. At this point, the battery should be immediately stopped from use. Check the connection between the charging system and the battery to ensure there are no abnormalities. Wait until the battery temperature drops to the normal range before continuing to use it. When using forklifts in high-temperature environments, it is important to provide good ventilation and heat dissipation conditions for the battery and avoid direct sunlight on it. In low-temperature environments, insulation measures should be taken, such as wrapping the battery with an insulation cover or charging and storing the battery indoors, to prevent the electrolyte from freezing due to low temperatures, which could damage the battery plates and casing. At the same time, it is necessary to regularly check whether the temperature sensor of the battery is working properly to ensure that the battery temperature can be monitored accurately and promptly.

5. Inspection of connection lines: Ensure that the current is unobstructed

5.1 Line integrity check

The lead-acid battery of the forklift is connected to the forklift circuit through connecting lines, and the integrity of these lines directly affects the transmission of current. When inspecting, carefully check whether the connecting lines are damaged, aged or exposed. Especially for the parts that are prone to friction and compression during vehicle operation, such as where the lines pass through the frame, special attention should be paid to inspection. Minor damage can be wrapped and repaired with insulating tape. If the damage is severe or the circuit is aged, a new connection circuit needs to be replaced. In addition, it is necessary to check whether the joints of the lines are firm and whether there is any loosening or oxidation. Loose joints will increase the contact resistance, resulting in unstable current transmission. Oxidized joints can affect the electrical conductivity and may even lead to poor contact in the circuit. For loose joints, a wrench should be used to tighten them. For oxidized joints, sandpaper can be used to sand them and then anti-oxidation grease can be applied to ensure a good connection.

5.2 Inspection of Circuit insulation performance

The insulation performance of the connecting lines is related to the electrical safety of the forklift. Use an insulation resistance tester to measure the insulation resistance value of the connected circuit. Generally speaking, the insulation resistance of the connection lines for lead-acid batteries should not be less than 0.5 megohms. If the insulation resistance value is too low, it indicates that there is a potential leakage hazard in the circuit, which may cause electrical system failures of the forklift and even lead to safety accidents such as fires. At this point, a comprehensive inspection of the circuit is required to identify the leakage points and carry out repairs or replacements. When checking the insulation performance of the circuit, make sure the vehicle is in a power-off state to prevent electric shock accidents.

6. Regular maintenance records: The basis for tracing problems

Establishing detailed regular maintenance records for forklift lead-acid batteries is an important means to prevent faults and trace problems. Maintenance records should include the date of each inspection, inspection items, inspection results, problems found and handling measures, etc. Through the analysis of maintenance records, the performance change trend of the battery can be understood, potential fault hazards can be discovered in a timely manner, and corresponding preventive measures can be taken. For instance, if the rate at which the electrolyte level drops is found to be accelerating, it may indicate that there is a microleakage problem with the battery, and further inspection is required. If the charging time gradually increases, it might be due to a decline in battery capacity. It is necessary to consider activating the battery or replacing it. Meanwhile, maintenance records are also important materials for equipment management and maintenance personnel to conduct technical exchanges and summarize experiences, which is conducive to improving the equipment maintenance level of the entire team.

In conclusion, the daily inspection of lead-acid batteries in forklifts is a meticulous and important task, covering multiple aspects such as appearance, electrolyte, charging system, temperature, and connection lines. By strictly following the inspection list for daily checks and maintenance, potential fault hazards can be identified and dealt with in a timely manner, which can effectively extend the service life of lead-acid batteries, improve the working efficiency of forklifts, and ensure the safety and smooth progress of logistics and warehousing operations. Equipment maintenance personnel and forklift operators should fully recognize the significance of daily inspections, implement them as a regular task, and provide reliable equipment support for the production and operation of enterprises.