Why does the lithium battery market need dehumidification air conditioning
According to data, in the first half of 2023, the added value of lithium-ion battery manufacturing industry above scale increased by 29.7% year-on-year. In addition to the previous power battery applications, benefiting from the rapid development of energy storage, lithium battery applications have ushered in a new growth point.
The harsh environmental requirements of lithium battery production also make dehumidification air conditioning indispensable in plant construction and production process. With the rapid growth of the lithium battery industry, this segment of the central air conditioning industry has developed rapidly.
Table of Contents
Why does lithium battery need dehumidification air conditioning
The main production process of lithium battery
Taking the typical square lithium iron phosphate battery as an example, its main battery production processes are slurry, coating, roll pressing, slitting, die cutting, winding, assembly, drying, primary injection, formation, secondary injection, laser sealing, leak detection, film, static, constant volume, sorting, module assembly, pack assembly, etc.
Analysis of influence of moisture on performance of lithium battery
There are many factors that affect the performance of lithium batteries, such as battery materials type, positive and negative electrode compaction density, moisture, coating surface density and electrolyte dosage.
Among them, water has a crucial impact on the performance of lithium-ion batteries, and water is a key factor that needs to be strictly controlled in the production process of lithium-ion batteries. For further information, you can also check top 10 lithium manganate material manufacturer.
Water has great influence on the first discharge capacity, internal resistance, cycle performance and thickness of lithium-ion battery. When the moisture content is high, the discharge capacity of the battery will be reduced, the internal resistance will be large, the cycle attenuation will be serious, and the thickness of the battery will also increase. Therefore, in order to ensure the performance of the battery, moisture needs to be strictly controlled in all aspects of the battery production process.
The demand for humidity in lithium battery production
According to the requirements of the lithium battery production process, the humidity requirements of the lithium battery production plant for the air conditioning system can be roughly divided into the following three categories:
Ordinary humidity requirements Air-conditioned rooms, such as negative coating rooms, the humidity control requirement is ≤60%, which can be achieved by cooling dehumidification.
Low-humidity demand air-conditioned rooms, such as positive roll room, positive strip room, positive die cutting room and positive split room, the humidity control requirement is ≤20%, and positive coating room, negative roll room, negative strip room, negative die cutting room and negative split room, the humidity control requirement is ≤45%, which is difficult to achieve through cooling dehumidification. Therefore, it is often processed by a rotary dehumidifier unit to meet the needs of use, and a first-stage runner is set in the unit.
Low dew point humidity requirements for air conditioning rooms, such as drying rooms, formation rooms and liquid injection rooms, the humidity control requirements for dew point ≤-50 ° C, or even higher, the demand of the existing first-stage wheel dehumidification unit is difficult to meet the process needs, the project is generally set up two-stage wheel dehumidification section to treat the room air to meet the needs of use.
The dehumidification method of lithium battery production industry
There are many kinds of current air dehumidification methods, including cooling dehumidification, liquid adsorbent dehumidification, solid adsorbent dehumidification, membrane dehumidification and so on.
In practical applications, a single dehumidification technology is difficult to meet the requirements, and from the perspective of energy conservation, the combined use of a variety of dehumidification technology can synthesize the advantages of various lithium battery technology, avoid their own shortcomings, and improve the efficiency of dehumidification while saving energy. At present, air dehumidification mainly includes cooling dehumidification and rotary dehumidification.
In the air conditioning dehumidification system, cooling dehumidification in a high temperature and humidity environment and the humidity requirements are not very strict conditions, the effect is better, but in the dehumidification amount is relatively large and the environment temperature is relatively low, the humidity and temperature requirements are relatively high, the use of cooling dehumidification is difficult to meet the humidity requirements, and there will be cold condensation phenomenon and energy consumption is relatively large.
The use of rotary dehumidifier for dehumidification is not affected by the air dew point, and the dehumidification amount is large. Rotary dehumidifier is a rotary dehumidifier made of solid absorbent.
It can not only greatly adhere to the hygroscopic agent, increase the surface area of the wet air and the hygroscopic agent in contact with each other, improve the work efficiency of the dehumidifier, but also has a high strength, and can be well applied to a variety of complex working environments. Therefore, the more commonly used dehumidification method in the lithium battery industry is rotary dehumidification.
Energy saving analysis of low humidity air conditioning system
The rotary dehumidification system has the advantages of independent dehumidification, good dehumidification effect under low humidity and air treatment to a lower dew point. In addition, rotary dehumidification can be combined with conventional air conditioning system into a rotary dehumidification air conditioning system to achieve independent control of temperature and humidity.
Avoid the drawbacks of conventional air conditioning system temperature and humidity control, improve energy efficiency, improve the air quality and control accuracy of the controlled space and other excellent performance, rotary dehumidification air conditioning system has therefore received great attention in practical applications.
However, the structure of the rotary dehumidification air conditioning system is complex, the operation cost is high, the air temperature rise in the dehumidification process is large, and the need to cool the air supply is limited, and the rotary dehumidification has a regeneration process, different regeneration methods have a significant impact on the economic performance of the air conditioning system, and the use of heating regeneration is faced with the problem of providing and selecting heating heat sources.
In view of the above reasons, the rotary dehumidification air conditioning and adsorption regeneration method has attracted the attention of many scholars, in recent years, the form and performance of the rotary dehumidification air conditioning system, the rotary dehumidification performance and the adsorbent regeneration method have been studied in various countries.
In the entire process of the lithium battery production plant, some process links produce a large amount of waste heat. The main ones are:
1) Coating process: the mixed slurry is coated on the positive and negative collector fluid, and the solvent in the slurry is removed by high-temperature baking and drying in the coating machine, so that the solid matter is well bonded to the substrate, and the high-temperature exhaust gas is discharged outdoors. The heating source of the coating machine is usually electric heating or thermal oil. The exhaust temperature can reach about 100℃.
2) Constant volume formation process: The process of charging and discharging test of the battery body in the formation cabinet or constant volume cabinet. The exhaust air temperature of the device is about 50 ° C to 60 ° C. When the air-cooled air compressor is used as the compressed air source, the exhaust temperature of the air compressor reaches 70 ° C ~80 ° C.
Therefore, in the future air conditioning system design, the waste heat continuously generated by the process equipment can be used to reduce the regenerative heating power consumption of the rotary dehumidification air conditioning unit. Reduce the operating energy consumption of a large number of wheel dehumidifier units in the lithium battery production plant.
Lucky
Hi, I am Lucky, graduated from a well-known university in China, now mainly engaged in article editing on lithium motorcycle batteries, and the battery swapping station, I am committed to offering services and solutions about battery swap station for various industries.
Why does the lithium battery market need dehumidification air conditioning
According to data, in the first half of 2023, the added value of lithium-ion battery manufacturing industry above scale increased by 29.7% year-on-year. In addition to the previous power battery applications, benefiting from the rapid development of energy storage, lithium battery applications have ushered in a new growth point.
The harsh environmental requirements of lithium battery production also make dehumidification air conditioning indispensable in plant construction and production process. With the rapid growth of the lithium battery industry, this segment of the central air conditioning industry has developed rapidly.
Why does lithium battery need dehumidification air conditioning
The main production process of lithium battery
Taking the typical square lithium iron phosphate battery as an example, its main battery production processes are slurry, coating, roll pressing, slitting, die cutting, winding, assembly, drying, primary injection, formation, secondary injection, laser sealing, leak detection, film, static, constant volume, sorting, module assembly, pack assembly, etc.
Analysis of influence of moisture on performance of lithium battery
There are many factors that affect the performance of lithium batteries, such as battery materials type, positive and negative electrode compaction density, moisture, coating surface density and electrolyte dosage.
Among them, water has a crucial impact on the performance of lithium-ion batteries, and water is a key factor that needs to be strictly controlled in the production process of lithium-ion batteries. For further information, you can also check top 10 lithium manganate material manufacturer.
Water has great influence on the first discharge capacity, internal resistance, cycle performance and thickness of lithium-ion battery. When the moisture content is high, the discharge capacity of the battery will be reduced, the internal resistance will be large, the cycle attenuation will be serious, and the thickness of the battery will also increase. Therefore, in order to ensure the performance of the battery, moisture needs to be strictly controlled in all aspects of the battery production process.
The demand for humidity in lithium battery production
According to the requirements of the lithium battery production process, the humidity requirements of the lithium battery production plant for the air conditioning system can be roughly divided into the following three categories:
The dehumidification method of lithium battery production industry
There are many kinds of current air dehumidification methods, including cooling dehumidification, liquid adsorbent dehumidification, solid adsorbent dehumidification, membrane dehumidification and so on.
In practical applications, a single dehumidification technology is difficult to meet the requirements, and from the perspective of energy conservation, the combined use of a variety of dehumidification technology can synthesize the advantages of various lithium battery technology, avoid their own shortcomings, and improve the efficiency of dehumidification while saving energy. At present, air dehumidification mainly includes cooling dehumidification and rotary dehumidification.
In the air conditioning dehumidification system, cooling dehumidification in a high temperature and humidity environment and the humidity requirements are not very strict conditions, the effect is better, but in the dehumidification amount is relatively large and the environment temperature is relatively low, the humidity and temperature requirements are relatively high, the use of cooling dehumidification is difficult to meet the humidity requirements, and there will be cold condensation phenomenon and energy consumption is relatively large.
The use of rotary dehumidifier for dehumidification is not affected by the air dew point, and the dehumidification amount is large. Rotary dehumidifier is a rotary dehumidifier made of solid absorbent.
It can not only greatly adhere to the hygroscopic agent, increase the surface area of the wet air and the hygroscopic agent in contact with each other, improve the work efficiency of the dehumidifier, but also has a high strength, and can be well applied to a variety of complex working environments. Therefore, the more commonly used dehumidification method in the lithium battery industry is rotary dehumidification.
Energy saving analysis of low humidity air conditioning system
The rotary dehumidification system has the advantages of independent dehumidification, good dehumidification effect under low humidity and air treatment to a lower dew point. In addition, rotary dehumidification can be combined with conventional air conditioning system into a rotary dehumidification air conditioning system to achieve independent control of temperature and humidity.
Avoid the drawbacks of conventional air conditioning system temperature and humidity control, improve energy efficiency, improve the air quality and control accuracy of the controlled space and other excellent performance, rotary dehumidification air conditioning system has therefore received great attention in practical applications.
However, the structure of the rotary dehumidification air conditioning system is complex, the operation cost is high, the air temperature rise in the dehumidification process is large, and the need to cool the air supply is limited, and the rotary dehumidification has a regeneration process, different regeneration methods have a significant impact on the economic performance of the air conditioning system, and the use of heating regeneration is faced with the problem of providing and selecting heating heat sources.
In view of the above reasons, the rotary dehumidification air conditioning and adsorption regeneration method has attracted the attention of many scholars, in recent years, the form and performance of the rotary dehumidification air conditioning system, the rotary dehumidification performance and the adsorbent regeneration method have been studied in various countries.
In the entire process of the lithium battery production plant, some process links produce a large amount of waste heat. The main ones are:
1) Coating process: the mixed slurry is coated on the positive and negative collector fluid, and the solvent in the slurry is removed by high-temperature baking and drying in the coating machine, so that the solid matter is well bonded to the substrate, and the high-temperature exhaust gas is discharged outdoors. The heating source of the coating machine is usually electric heating or thermal oil. The exhaust temperature can reach about 100℃.
2) Constant volume formation process: The process of charging and discharging test of the battery body in the formation cabinet or constant volume cabinet. The exhaust air temperature of the device is about 50 ° C to 60 ° C. When the air-cooled air compressor is used as the compressed air source, the exhaust temperature of the air compressor reaches 70 ° C ~80 ° C.
Therefore, in the future air conditioning system design, the waste heat continuously generated by the process equipment can be used to reduce the regenerative heating power consumption of the rotary dehumidification air conditioning unit. Reduce the operating energy consumption of a large number of wheel dehumidifier units in the lithium battery production plant.