The maintenance work of the valve-regulated lead-acid battery was discussed.
Because of the valve-regulated lead-acid battery (VRLAB), it has the following advantages:
Can be placed horizontally, stacked, can be placed together with communication equipment to save space; poor liquid design eliminates the need to carry out specific gravity measurement during maintenance, suitable for large current discharge; in general, hydrogen and oxygen composite is better, does not produce hydrogen Charging does not produce sour gas and pollutes the environment, and so on. Therefore, it has been widely used in the field of communication.
When the valve-regulated battery was used in the early 1990s, it was once called "maintenance-free battery", which is actually a misleading, and the quality of the early remote valve-controlled battery products is not high, often in use. There will be some faults of one kind or another.
Of course, with the development of computer technology, the emergence of large-scale integrated circuit devices, and the continuous improvement of switching power supplies, UPS power supply technologies, etc., power system equipment has made great progress, in the safety and reliability of power supply, etc. The aspect has been greatly improved, and the workload of power system equipment maintenance has also been reduced. However, the valve-regulated battery that is matched with the power system equipment still has some faults from time to time. Therefore, the maintenance of the valve-controlled battery is crucial in both the DC power supply system and the AC/DC uninterruptible power supply system.
So, how can we maintain a valve-regulated battery under current conditions? The author wants to talk about personal opinions on this issue.
First, the quality of the valve-controlled battery should be analyzed. The quality of VR battery operation is determined by three aspects:
First, product quality
Second, the quality of installation
The third is the quality of operation and maintenance.
These three aspects should be said to be very important. Especially the quality of the product. This is the key to maintaining a good quality of operation of the valve-controlled battery, and is related to every step in the production process of the battery, from manufacturing lead powder to packaging and storage. Therefore, the thickness and weight of the grid, the formulation of the lead paste, the permeability of the separator, the technical design of the safety valve, the filling method of the electrolyte, and the control and synthesis of the electrolyte injection amount, the housing material And the sealing of the shell cover and the pole pile, the cover between the shell and the shell, etc., and the strict control of the various aspects.
For installation quality, it also includes storage, installation, capacity experiments and other aspects. These aspects will directly affect the operation and maintenance of the VRLA in the future. Therefore, during the process of handling and storage, care should be taken not to collide. During the installation process, pay attention to the match between the splicing strip and the battery pole. Be careful. The uneven pole pile is leveled. When tightening poles, the force used should be neither too large nor too small.
If it is too large, the copper sleeve in the pole pile will overflow, and the force will be too small, which will cause poor contact between the bus bar and the pole pile. Therefore, it is better to use the wrench provided by the manufacturer with over-force trip, or according to the manufacturer. For the reference kilogram force, use the corresponding kilogram wrench. In the installation, the hydraulics also pay attention to the following aspects: First, the battery positive and positive poles, the negative pole and the negative pole of each group between the battery and the DC screen should be as uniform as possible to maintain the balance between the battery packs during high current discharge; The connection between the positive and negative busbars of the battery pack and the battery bus bar should be firm and reliable. 3. After installation, don't forget to recharge the battery.
For the quality of maintenance, it is also important to ensure the normal operation of the valve-controlled battery. If the maintenance quality is high, the valve-regulated battery can be maximized and the service life can be extended. Therefore, the electric maintenance personnel should carry out the maintenance work under the premise of fully understanding the requirements of the valve-controlled battery product specification, and clarify the following aspects and problems in the maintenance work;
(1) Relationship between temperature and capacity
The approximate standard given by the GNB battery (valve-controlled battery) on the Internet is that the capacity of the battery is 100% at 25 ° C; when it is below 25 ° C, the capacity of the battery is reduced by half for every 10 ° C increase; When the temperature is below 25 °C, the relationship between temperature and capacity is shown in Beauty 1.
The capacity of the valve-controlled battery changes with the change of temperature. The maintenance personnel must carefully adjust the discharge current of the battery according to the actual temperature change, and at the same time control the temperature of the battery to keep it at 22 ° C ~ 25 Within °C.
(2) Relationship between charging, discharging, life and capacity
a. The relationship between charging and life
Maintenance of VRLA batteries requires the establishment of an accurate charging system and implementation, in order to achieve optimal performance and longest service life of the battery [1], a large number of research results at home and abroad indicate that the charging method determines The life of the battery used, some batteries are not so bad to use, it is better to say that the charging method is not properly damaged.
In this convenience, many battery manufacturers and research institutes or schools in China have done similar experiments. For example, there is one unit, the battery is divided into two groups for experiment, one group uses the normal constant voltage current limiting method for the full capacity life test, and the other group uses the stage constant current charging method to control the charging capacity, and is used in the later stage of charging. The short-time medium current impact method is used to test the capacity cycle life.
As a result, the two groups of batteries have different cycle life due to different charging methods, and the battery with a constant current charging mode has a longer cycle life. It can be seen that the constant voltage current limiting charging method currently widely used, especially in the late charging stage, is quite lacking. Due to the current rectification equipment, especially the switching power supply does not have constant current characteristics, there are still some difficulties in adopting the second charging method, so further exploration is needed for this problem.
In addition, some research departments are currently exploring the use of pulse charging to charge the valve-regulated battery. The main process is to divide the pulse charge into one or several stages, each stage having several pulse periods. For example, the whole process is charging for 10 minutes, charging for 3 minutes, discharging for 3 seconds, parking for 1.75 minutes, and charging for 15 minutes in the final stage and resting for several hours to cool the electrolyte. It is said that this method is ideal and can eliminate sulfation [2].
b. Relationship between discharge and capacity
As we all know, discharge currents of different magnifications will make batteries have different capacities.
The battery capacity configured in the communication power supply DC power supply system is also different, and the capacity of the battery to operate under the actual discharge current should have an accurate calculation. It is worth noting here that the formation of lead sulfate under low current discharge conditions is very difficult to redox because the size of lead sulfate particles formed under small current discharge is much larger than that under large current discharge conditions. That is to say, the crystal formation speed under the high current condition is slower than that under the small current condition, and the crystal is quickly redoxed when it is too late to grow, so the particles are relatively small. Under low current conditions, larger lead sulfate crystals are not easily reduced. If the lead sulfate crystals are not cleaned for a long time, it will inevitably affect the capacity and service life of the battery.
Because of the valve-regulated lead-acid battery (VRLAB), it has the following advantages:
Can be placed horizontally, stacked, can be placed together with communication equipment to save space; poor liquid design eliminates the need to carry out specific gravity measurement during maintenance, suitable for large current discharge; in general, hydrogen and oxygen composite is better, does not produce hydrogen Charging does not produce sour gas and pollutes the environment, and so on. Therefore, it has been widely used in the field of communication.
When the valve-regulated battery was used in the early 1990s, it was once called "maintenance-free battery", which is actually a misleading, and the quality of the early remote valve-controlled battery products is not high, often in use. There will be some faults of one kind or another.
Of course, with the development of computer technology, the emergence of large-scale integrated circuit devices, and the continuous improvement of switching power supplies, UPS power supply technologies, etc., power system equipment has made great progress, in the safety and reliability of power supply, etc. The aspect has been greatly improved, and the workload of power system equipment maintenance has also been reduced. However, the valve-regulated battery that is matched with the power system equipment still has some faults from time to time. Therefore, the maintenance of the valve-controlled battery is crucial in both the DC power supply system and the AC/DC uninterruptible power supply system.
So, how can we maintain a valve-regulated battery under current conditions? The author wants to talk about personal opinions on this issue.
First, the quality of the valve-controlled battery should be analyzed. The quality of VR battery operation is determined by three aspects:
First, product quality
Second, the quality of installation
The third is the quality of operation and maintenance.
These three aspects should be said to be very important. Especially the quality of the product. This is the key to maintaining a good quality of operation of the valve-controlled battery, and is related to every step in the production process of the battery, from manufacturing lead powder to packaging and storage. Therefore, the thickness and weight of the grid, the formulation of the lead paste, the permeability of the separator, the technical design of the safety valve, the filling method of the electrolyte, and the control and synthesis of the electrolyte injection amount, the housing material And the sealing of the shell cover and the pole pile, the cover between the shell and the shell, etc., and the strict control of the various aspects.
For installation quality, it also includes storage, installation, capacity experiments and other aspects. These aspects will directly affect the operation and maintenance of the VRLA in the future. Therefore, during the process of handling and storage, care should be taken not to collide. During the installation process, pay attention to the match between the splicing strip and the battery pole. Be careful. The uneven pole pile is leveled. When tightening poles, the force used should be neither too large nor too small.
If it is too large, the copper sleeve in the pole pile will overflow, and the force will be too small, which will cause poor contact between the bus bar and the pole pile. Therefore, it is better to use the wrench provided by the manufacturer with over-force trip, or according to the manufacturer. For the reference kilogram force, use the corresponding kilogram wrench. In the installation, the hydraulics also pay attention to the following aspects: First, the battery positive and positive poles, the negative pole and the negative pole of each group between the battery and the DC screen should be as uniform as possible to maintain the balance between the battery packs during high current discharge; The connection between the positive and negative busbars of the battery pack and the battery bus bar should be firm and reliable. 3. After installation, don't forget to recharge the battery.
For the quality of maintenance, it is also important to ensure the normal operation of the valve-controlled battery. If the maintenance quality is high, the valve-regulated battery can be maximized and the service life can be extended. Therefore, the electric maintenance personnel should carry out the maintenance work under the premise of fully understanding the requirements of the valve-controlled battery product specification, and clarify the following aspects and problems in the maintenance work;
(1) Relationship between temperature and capacity
The approximate standard given by the GNB battery (valve-controlled battery) on the Internet is that the capacity of the battery is 100% at 25 ° C; when it is below 25 ° C, the capacity of the battery is reduced by half for every 10 ° C increase; When the temperature is below 25 °C, the relationship between temperature and capacity is shown in Beauty 1.
The capacity of the valve-controlled battery changes with the change of temperature. The maintenance personnel must carefully adjust the discharge current of the battery according to the actual temperature change, and at the same time control the temperature of the battery to keep it at 22 ° C ~ 25 Within °C.
(2) Relationship between charging, discharging, life and capacity
a. The relationship between charging and life
Maintenance of VRLA batteries requires the establishment of an accurate charging system and implementation, in order to achieve optimal performance and longest service life of the battery [1], a large number of research results at home and abroad indicate that the charging method determines The life of the battery used, some batteries are not so bad to use, it is better to say that the charging method is not properly damaged.
In this convenience, many battery manufacturers and research institutes or schools in China have done similar experiments. For example, there is one unit, the battery is divided into two groups for experiment, one group uses the normal constant voltage current limiting method for the full capacity life test, and the other group uses the stage constant current charging method to control the charging capacity, and is used in the later stage of charging. The short-time medium current impact method is used to test the capacity cycle life.
As a result, the two groups of batteries have different cycle life due to different charging methods, and the battery with a constant current charging mode has a longer cycle life. It can be seen that the constant voltage current limiting charging method currently widely used, especially in the late charging stage, is quite lacking. Due to the current rectification equipment, especially the switching power supply does not have constant current characteristics, there are still some difficulties in adopting the second charging method, so further exploration is needed for this problem.
In addition, some research departments are currently exploring the use of pulse charging to charge the valve-regulated battery. The main process is to divide the pulse charge into one or several stages, each stage having several pulse periods. For example, the whole process is charging for 10 minutes, charging for 3 minutes, discharging for 3 seconds, parking for 1.75 minutes, and charging for 15 minutes in the final stage and resting for several hours to cool the electrolyte. It is said that this method is ideal and can eliminate sulfation [2].
b. Relationship between discharge and capacity
As we all know, discharge currents of different magnifications will make batteries have different capacities.
The battery capacity configured in the communication power supply DC power supply system is also different, and the capacity of the battery to operate under the actual discharge current should have an accurate calculation. It is worth noting here that the formation of lead sulfate under low current discharge conditions is very difficult to redox because the size of lead sulfate particles formed under small current discharge is much larger than that under large current discharge conditions. That is to say, the crystal formation speed under the high current condition is slower than that under the small current condition, and the crystal is quickly redoxed when it is too late to grow, so the particles are relatively small. Under low current conditions, larger lead sulfate crystals are not easily reduced. If the lead sulfate crystals are not cleaned for a long time, it will inevitably affect the capacity and service life of the battery.
1. The inner core of the electric heat pipe is made of high-quality stainless steel or other materials, with a coat of PTFE, which is highly corrosion-resistant and suitable for heating various corrosive liquids.
2. Low surface power design (1.5kw /CM) to ensure the service life of the product.
3. The installation position of the electric heater should be paid attention to prevent the solid in the solution from depositing on the surface of the electric heater, or the liquid is too thick and the liquid level is too low, which will cause the teflon tube (PTFE) to be burnt due to the poor surface heat.
4. The shape is divided into vertical type and bottom heating "L" and "Z" type.
Teflon Electric​ Heater,PTFE Electric​ Heater,Teflon Ptfe Immersion Heater Element
Guangzhou Quanxu Technology Co Ltd , https://www.anticorrosionpigment.com