News

In the industrial field, forklifts, as important equipment for material handling, the performance of their power source - lead-acid batteries - is of vital importance. The performance of lead-acid batteries in forklifts directly affects the working efficiency, usage cost and service life of forklifts. A thorough understanding of the key performance indicators of lead-acid batteries for forklifts is of great guiding significance for the rational selection, efficient use and maintenance of forklifts.

1. Capacity

Capacity is one of the most fundamental and important performance indicators of forklift lead-acid batteries. It reflects the battery's ability to store electrical energy and is usually expressed in ampere-hours (Ah).

For forklifts, the size of the capacity directly determines the continuous working time of the forklift. In actual working conditions, the working intensity and load conditions of forklifts vary, which requires the selection of batteries of appropriate capacity based on specific needs. If the selected battery capacity is too small, the forklift may stop working prematurely due to insufficient power during operation, affecting work efficiency. However, if the capacity is too large, it will increase the cost of the equipment and the weight of the vehicle itself, and may also lead to the waste of batteries.

In addition, the actual capacity of a battery is affected by factors such as temperature and discharge rate. In low-temperature environments, the chemical reaction rate of storage batteries slows down, and the utilization rate of active substances decreases, resulting in a decline in actual capacity. At high discharge rates, due to the intensification of polarization phenomena, the internal resistance of the battery increases, which will also reduce the available capacity. Therefore, when evaluating and selecting the capacity of lead-acid batteries for forklifts, it is necessary to comprehensively consider these influencing factors to ensure that the batteries can meet the working requirements of forklifts under various working conditions.

2. Voltage

The voltage of forklift lead-acid batteries mainly includes the rated voltage and the actual working voltage. The common rated voltages of lead-acid batteries for forklifts include 24V, 36V, 48V, 80V, etc. Batteries with different rated voltages are suitable for forklifts of different powers and specifications.

The rated voltage is the standard voltage specified during the design and manufacture of a storage battery, which reflects the basic electrical characteristics of the battery. However, the actual working voltage will change along with the charging and discharging process of the battery. During the charging process, the voltage of the battery gradually increases. When it approaches full charge, the voltage will reach a relatively stable value. During the discharge process, the voltage will gradually decrease. When the voltage drops to a certain extent, the battery needs to be charged; otherwise, it will have a serious impact on the battery's lifespan.

Understanding the voltage characteristics of the battery is crucial for the electrical system design and normal operation of forklifts. The electrical equipment such as the motor and controller of a forklift all need to operate within an appropriate voltage range. Both excessively high and low voltages may cause damage to the equipment or a decline in performance. Meanwhile, by monitoring the voltage changes of the battery, the charging and discharging status of the battery can also be determined, and timely charging and maintenance can be carried out to ensure the normal operation of the forklift.

3. Charging and Discharging Performance

●1.Charging performance

The charging performance of lead-acid batteries in forklifts directly affects their usage efficiency and service life. Good charging performance should feature fast charging speed, high charging efficiency and minimal damage to the battery. At present, common charging methods include constant current charging, constant voltage charging and staged charging, etc.

Constant current charging refers to maintaining a constant charging current during the charging process. This method has a relatively slow charging speed, but it can ensure uniform charging of the battery and is suitable for charging new batteries or batteries that have been deeply discharged. Constant voltage charging keeps the charging voltage constant. As charging proceeds, the charging current gradually decreases. This method has a relatively fast charging speed, but it may lead to uneven battery charging. Staged charging combines the advantages of constant current charging and constant voltage charging. It first charges rapidly in a constant current manner and then switches to constant voltage charging when the voltage reaches a certain value. This can ensure charging efficiency while reducing damage to the battery.

In addition, temperature control during the charging process is also very important. Excessively high temperatures will accelerate the aging and decomposition of substances inside the battery, reducing its performance and lifespan. Therefore, modern forklift lead-acid battery charging systems are usually equipped with temperature sensors and heat dissipation devices to ensure that the charging process takes place within an appropriate temperature range.

●2. Discharge performance

The discharge performance of a storage battery is mainly reflected in its ability to stably output electrical energy and its performance under different load conditions. During the operation of a forklift, the load conditions are constantly changing. For instance, the weight of the goods being moved and the slope of the vehicle can all cause fluctuations in the discharge current. High-quality lead-acid batteries for forklifts should have excellent high-current discharge capabilities, capable of providing sufficient electrical energy in an instant to meet the demands of forklift starting, acceleration, and climbing.

Meanwhile, the voltage stability during the discharge process is also of vital importance. Stable voltage output can ensure the normal operation of forklift electrical equipment and prevent equipment failure caused by excessive voltage fluctuations. In addition, the depth of discharge of the battery also affects its lifespan. Excessive discharge can cause the active substances on the battery plates to fall off, reducing the battery's capacity and performance. Therefore, during use, excessive discharge of the battery should be avoided and it should be charged in a timely manner.

4. Cycle Life

Cycle life refers to the number of times a forklift lead-acid battery can be charged and discharged repeatedly under certain charging and discharging conditions. It is an important indicator for measuring the service life of storage batteries. Generally speaking, the cycle life of lead-acid batteries in forklifts is around 1,500 times. The specific value is affected by factors such as the depth of charging and discharging, charging current, and operating temperature.

The depth of charging and discharging is one of the key factors affecting the cycle life. The deeper the depth of charging and discharging, the higher the degree to which the active substances on the battery plates participate in the chemical reaction, and the greater the loss of the active substances, which leads to a shortened cycle life.

The magnitude of the charging current also has an impact on the cycle life. Excessive charging current will intensify the heating inside the battery, accelerate the aging and decomposition of the substances inside the battery, and reduce the cycle life. If the charging current is too small, it will prolong the charging time and affect the efficiency of the forklift. Therefore, choosing the appropriate charging current is crucial for extending the cycle life of the battery.

The influence of temperature on cycle life cannot be ignored either. In a high-temperature environment, the chemical reaction rate inside the battery increases, the loss of active substances also increases accordingly, and the cycle life shortens. In low-temperature environments, the charging and discharging performance of batteries declines, which will also have an adverse impact on their cycle life. Therefore, when using and storing forklift lead-acid batteries, it is necessary to maintain an appropriate temperature environment as much as possible.

5. Self-Discharge Rate

Self-discharge rate refers to the rate at which a battery loses its electrical energy on its own when it is not in use. Self-discharge of lead-acid batteries in forklifts is a normal physical and chemical phenomenon, mainly caused by chemical reactions between the active substances inside the battery and the electrolyte, as well as micro-short circuits between the battery plates and other reasons.

The level of self-discharge rate directly affects the storage performance and ease of use of the battery. If the self-discharge rate is too high, the battery will quickly lose power during the idle period. When it is used again, it needs to be charged for a long time. This not only increases the usage cost but may also affect the normal operation of the forklift. Generally speaking, high-quality lead-acid batteries for forklifts have a relatively low self-discharge rate, with a monthly self-discharge rate not exceeding 5% to 10% at normal temperature.

To reduce the self-discharge rate, in the manufacturing process of storage batteries, high-quality raw materials and advanced production techniques are usually adopted to minimize impurities and micro-short circuits inside the batteries. During use and storage, keeping the battery clean, preventing electrolyte leakage and impurities from entering the battery interior, and storing the battery in a cool and dry environment can also help reduce the self-discharge rate.

6. Internal Resistance

Internal resistance refers to the resistance inside the lead-acid battery of a forklift, which includes plate resistance, electrolyte resistance, separator resistance, etc. The magnitude of internal resistance directly affects the charging and discharging performance and output power of the battery.

During the charging process, the internal resistance generates heat, resulting in a decrease in charging efficiency. During the discharge process, the internal resistance will cause a voltage drop, reducing the output voltage of the battery. The greater the internal resistance is, the more obvious this influence will be. When a battery ages or malfunctions, its internal resistance usually increases. Therefore, measuring the internal resistance can to a certain extent determine the health condition of the battery.

The main factors affecting internal resistance include the structure, materials and temperature of the battery. Generally speaking, the thinner the plates, the higher the concentration of the electrolyte and the higher the temperature, the smaller the internal resistance. In practical use, it is necessary to pay attention to maintaining the appropriate temperature of the battery, avoid overcharging and discharging as well as discharging with high current, so as to reduce the increase in internal resistance and ensure the performance of the battery.

7. Security

Safety is an important performance indicator of forklift lead-acid batteries, which is related to the personal safety of operators and the production safety of enterprises. The potential safety hazards of lead-acid batteries during use mainly include battery leakage, explosion, fire, etc.

Battery leakage may corrode the metal parts of forklifts, causing electrical short circuits. Meanwhile, the sulfuric acid in the electrolyte is corrosive and can cause harm to the skin and eyes of the operators. To prevent leakage, batteries are usually designed and manufactured with a sealed structure, and the sealing treatment of parts such as the battery casing and terminal posts is strengthened.

During the charging process of the battery, if the hydrogen gas produced cannot be discharged in time, when the hydrogen concentration reaches a certain level, it may cause an explosion upon encountering an open flame or electric spark. Therefore, forklift lead-acid batteries are usually equipped with exhaust devices to ensure that hydrogen can be discharged in a timely manner. At the same time, smoking and open flames should be strictly prohibited in the charging area, and good ventilation conditions should be maintained to reduce the risk of explosion.

In addition, internal short circuits, overcharging, and overdischarging of the battery may also cause the battery to heat up, leading to fire accidents. To enhance safety, modern forklift lead-acid batteries are usually equipped with overcharge, overdischarge and short-circuit protection devices to monitor the battery's working status in real time. Once any abnormal situation occurs, the power supply is cut off promptly to prevent the occurrence of safety accidents.

In conclusion, the key performance indicators of forklift lead-acid batteries, such as capacity, voltage, charge and discharge performance, cycle life, self-discharge rate, internal resistance and safety, are interrelated and influence each other, jointly determining the performance and quality of the batteries. In the process of selecting, using and maintaining lead-acid batteries for forklifts, only by thoroughly understanding these performance indicators can we reasonably choose suitable batteries, correctly use and maintain them, improve the working efficiency of forklifts, reduce usage costs, extend the service life of batteries, and ensure the safety and smooth progress of industrial production.