Research on battery cooling technology of power battery of new energy vehicles
Table of Contents
New energy vehicles are new energy vehicles driven by electricity, the battery device in a long time drive state, the ratio of electrical energy and thermal energy will appear negative growth, once the battery heat generated than the thermal energy output, will intensify the degree of loss of electrical energy, greatly reducing the service life of the battery device. In order to promote the further development of the new energy vehicle industry, major automobile enterprises need to improve the development and optimization of power batteries, apply battery cooling technology to disperse battery devices in a timely manner, effectively extend the life cycle of batteries and create more economic profits for automobile enterprises.
New energy car battery
Lithium-ion battery
Ternary lithium battery itself has a very high energy density and voltage, with the application advantages of light weight and low pollution, lithium-ion battery application life is much longer than other types of batteries, in China’s new energy vehicle industry has a good development scenario, suitable for the development of energy-saving and environmental protection industry.
NiMH battery
NiMH batteries are alkaline batteries with the advantages of long service life and high overall discharge power, but the memory effect of NiMH batteries is obvious and the manufacturing cost is relatively high, so they are mainly used in power tools and will be fully popularized in the automotive field in the near future.
Lead-acid batteries
Lead-acid batteries are large in size and weight, can release relatively low energy and have a relatively short service life, but the raw materials used in their production are not costly and their stability is relatively excellent, so they can be recycled again. At this stage, they are widely used in electric tricycles and motorcycle battery replacement, and have the highest share in the energy market.
Fuel cell
With the advantages of low harmful gas emissions and low noise pollution, fuel cells have a wide scope for development in the field of new energy vehicles. The working principle of fuel cell is to convert chemical energy into electricity. However, the level of fuel cell technology and infrastructure facilities in China are still different compared with those in developed countries. For this reason, China needs to increase the level of research on power cells to ensure that fuel cells can be well applied in new energy vehicles.
New energy vehicle battery cooling system
The battery cooling system of new energy vehicles is mainly composed of power system cooling and power supply system cooling, where the power system cooling is for the drive motor, controller, etc., and the power supply system cooling is mainly for the power battery and vehicle charger. The spacing of the power battery of the new energy vehicle has a certain influence on the working temperature of the whole battery pack, and the increase of the battery distance will also increase the working temperature of the battery pack, while the temperature distribution is relatively uniform during the period of battery pack concentration.
The power battery of new energy vehicles is mainly converted from chemical energy to electrical energy, and then from electrical energy to kinetic energy of new energy vehicles, and the heat generated in the process of energy conversion can not be released in a timely manner, will cause a significant increase in the temperature around the power battery, which will have an impact on the stability of lithium batteries. At the same time, the power battery is always in a high temperature state, which will also have an impact on the performance of the battery, and will greatly shorten the service life of the battery.
With the application of battery cooling system, new energy vehicles can ensure that the battery pack is always in a suitable environment for energy conversion, ensuring the maximum performance of the vehicle. To this end, the battery cooling system can make full use of the automotive battery pack heat management model to properly regulate the temperature of the power battery, providing heat to the battery when it is relatively low, and cooling it when it is too high, ensuring that the power battery is always in the best working condition and improving the overall performance of the power battery.
Battery cooling technology analysis of new energy vehicle power battery
Air battery cooling technology
This battery cooling technology uses air as the cooling medium to achieve the purpose of battery cooling with the help of convective heat exchange principle. Air-cooled battery technology itself has the characteristics of low maintenance cost and low manufacturing cost, so it can be widely used as a protection device for power batteries. At the same time, air battery cooling technology in the application process is also subject to the specific heat capacity of air and the nature of the thermal conductivity, so the air-cooled battery technology is not very efficient battery cooling.
Liquid battery cooling technology
This battery cooling technology has the advantages of high specific heat capacity coefficient and high heat transfer coefficient, using liquid media to achieve power battery cooling. Liquid battery cooling technology applied cooling medium is mainly liquid phase substances, such as ethylene glycol, water and refrigerants can be used as refrigerants to achieve the effect of battery cooling. Liquid battery cooling technology is divided into direct cooling means and indirect cooling means according to the different contact methods. Direct battery cooling means is to completely submerge the battery module in the insulating cooling liquid, through the realization of the direct contact between the cooling liquid and the battery pack to achieve the purpose of battery cooling.
Indirect battery cooling means is to set up cooling coils around the battery pack, by the cooling liquid flow in which the purpose of battery cooling by convection heat transfer and cooling means. The cooling medium often applied at this stage is the new electronic cooling medium NOVEC 7000, which adopts the cooling method of heat transfer and medium phase change heat absorption to ensure that the working temperature of the battery pack is always maintained at about 35℃, while the glycol medium applied in the past will gradually increase the working temperature of the battery pack under multiple cycles. Therefore, the new electronic cooling medium NOVEC 7000 has a good prospect of application in the battery cooling system of new energy vehicle power battery.
Heat pipe battery cooling technology
This battery cooling technology mainly uses well-sealed hollow tube equipment for cooling, by filling the hollow tube equipment with a phase change process, and setting up evaporators and condensers at both ends of the tube to achieve the cooling effect of the battery. The principle of heat pipe battery cooling technology is to use the evaporator to absorb sufficient heat, the closed state of the hollow tube capillary core of liquid vaporization to produce a certain amount of air pressure, so that it gradually flow in the direction of the condenser, the gas will release heat when passing through the condenser, the gas will re-consolidate into a liquid to continue to absorb heat, and so on in the form of repeated cycles to achieve the purpose of battery cooling.
Phase change material battery cooling technology
This battery cooling technology mainly uses the principle of phase change heat absorption to achieve the purpose of reducing the working temperature of the battery pack. The phase change material itself has the technical characteristics of non-toxic and harmless, excellent thermal stability and low application cost. Heat pipe battery cooling technology in the specific application process does not need to rely on any channel equipment or electrical equipment, can ensure the overall temperature uniformity of the battery pack, to avoid the battery pack has a hot spot situation, so in the application of the link can ensure the safety of the battery pack operation.
Summary
In the context of sustainable development, the new energy vehicle industry is developing rapidly and is committed to solving the problems of energy consumption and environmental pollution in various aspects. Nowadays, the electric capacity of battery pack and the number of battery modules in new energy vehicles are gradually increasing, and the heat released from the power battery pack is also greatly increased.
The application of new energy vehicle power battery cooling technology can further extend the service life of the battery and effectively ensure the safety of the battery pack. Therefore, in the process of designing the battery cooling system of new energy vehicle power battery, it is necessary to flexibly apply air battery cooling technology, liquid battery cooling technology, heat pipe battery cooling technology and phase change material battery cooling technology to pay attention to the thermal management of power battery and promote the sustainable development of new energy vehicles.
Research on battery cooling technology of power battery of new energy vehicles
New energy vehicles are new energy vehicles driven by electricity, the battery device in a long time drive state, the ratio of electrical energy and thermal energy will appear negative growth, once the battery heat generated than the thermal energy output, will intensify the degree of loss of electrical energy, greatly reducing the service life of the battery device. In order to promote the further development of the new energy vehicle industry, major automobile enterprises need to improve the development and optimization of power batteries, apply battery cooling technology to disperse battery devices in a timely manner, effectively extend the life cycle of batteries and create more economic profits for automobile enterprises.
New energy car battery
Lithium-ion battery
Ternary lithium battery itself has a very high energy density and voltage, with the application advantages of light weight and low pollution, lithium-ion battery application life is much longer than other types of batteries, in China’s new energy vehicle industry has a good development scenario, suitable for the development of energy-saving and environmental protection industry.
NiMH battery
NiMH batteries are alkaline batteries with the advantages of long service life and high overall discharge power, but the memory effect of NiMH batteries is obvious and the manufacturing cost is relatively high, so they are mainly used in power tools and will be fully popularized in the automotive field in the near future.
Lead-acid batteries
Lead-acid batteries are large in size and weight, can release relatively low energy and have a relatively short service life, but the raw materials used in their production are not costly and their stability is relatively excellent, so they can be recycled again. At this stage, they are widely used in electric tricycles and motorcycle battery replacement, and have the highest share in the energy market.
Fuel cell
With the advantages of low harmful gas emissions and low noise pollution, fuel cells have a wide scope for development in the field of new energy vehicles. The working principle of fuel cell is to convert chemical energy into electricity. However, the level of fuel cell technology and infrastructure facilities in China are still different compared with those in developed countries. For this reason, China needs to increase the level of research on power cells to ensure that fuel cells can be well applied in new energy vehicles.
New energy vehicle battery cooling system
The battery cooling system of new energy vehicles is mainly composed of power system cooling and power supply system cooling, where the power system cooling is for the drive motor, controller, etc., and the power supply system cooling is mainly for the power battery and vehicle charger. The spacing of the power battery of the new energy vehicle has a certain influence on the working temperature of the whole battery pack, and the increase of the battery distance will also increase the working temperature of the battery pack, while the temperature distribution is relatively uniform during the period of battery pack concentration.
The power battery of new energy vehicles is mainly converted from chemical energy to electrical energy, and then from electrical energy to kinetic energy of new energy vehicles, and the heat generated in the process of energy conversion can not be released in a timely manner, will cause a significant increase in the temperature around the power battery, which will have an impact on the stability of lithium batteries. At the same time, the power battery is always in a high temperature state, which will also have an impact on the performance of the battery, and will greatly shorten the service life of the battery.
With the application of battery cooling system, new energy vehicles can ensure that the battery pack is always in a suitable environment for energy conversion, ensuring the maximum performance of the vehicle. To this end, the battery cooling system can make full use of the automotive battery pack heat management model to properly regulate the temperature of the power battery, providing heat to the battery when it is relatively low, and cooling it when it is too high, ensuring that the power battery is always in the best working condition and improving the overall performance of the power battery.
Battery cooling technology analysis of new energy vehicle power battery
Air battery cooling technology
This battery cooling technology uses air as the cooling medium to achieve the purpose of battery cooling with the help of convective heat exchange principle. Air-cooled battery technology itself has the characteristics of low maintenance cost and low manufacturing cost, so it can be widely used as a protection device for power batteries. At the same time, air battery cooling technology in the application process is also subject to the specific heat capacity of air and the nature of the thermal conductivity, so the air-cooled battery technology is not very efficient battery cooling.
Liquid battery cooling technology
This battery cooling technology has the advantages of high specific heat capacity coefficient and high heat transfer coefficient, using liquid media to achieve power battery cooling. Liquid battery cooling technology applied cooling medium is mainly liquid phase substances, such as ethylene glycol, water and refrigerants can be used as refrigerants to achieve the effect of battery cooling. Liquid battery cooling technology is divided into direct cooling means and indirect cooling means according to the different contact methods. Direct battery cooling means is to completely submerge the battery module in the insulating cooling liquid, through the realization of the direct contact between the cooling liquid and the battery pack to achieve the purpose of battery cooling.
Indirect battery cooling means is to set up cooling coils around the battery pack, by the cooling liquid flow in which the purpose of battery cooling by convection heat transfer and cooling means. The cooling medium often applied at this stage is the new electronic cooling medium NOVEC 7000, which adopts the cooling method of heat transfer and medium phase change heat absorption to ensure that the working temperature of the battery pack is always maintained at about 35℃, while the glycol medium applied in the past will gradually increase the working temperature of the battery pack under multiple cycles. Therefore, the new electronic cooling medium NOVEC 7000 has a good prospect of application in the battery cooling system of new energy vehicle power battery.
Heat pipe battery cooling technology
This battery cooling technology mainly uses well-sealed hollow tube equipment for cooling, by filling the hollow tube equipment with a phase change process, and setting up evaporators and condensers at both ends of the tube to achieve the cooling effect of the battery. The principle of heat pipe battery cooling technology is to use the evaporator to absorb sufficient heat, the closed state of the hollow tube capillary core of liquid vaporization to produce a certain amount of air pressure, so that it gradually flow in the direction of the condenser, the gas will release heat when passing through the condenser, the gas will re-consolidate into a liquid to continue to absorb heat, and so on in the form of repeated cycles to achieve the purpose of battery cooling.
Phase change material battery cooling technology
This battery cooling technology mainly uses the principle of phase change heat absorption to achieve the purpose of reducing the working temperature of the battery pack. The phase change material itself has the technical characteristics of non-toxic and harmless, excellent thermal stability and low application cost. Heat pipe battery cooling technology in the specific application process does not need to rely on any channel equipment or electrical equipment, can ensure the overall temperature uniformity of the battery pack, to avoid the battery pack has a hot spot situation, so in the application of the link can ensure the safety of the battery pack operation.
Summary
In the context of sustainable development, the new energy vehicle industry is developing rapidly and is committed to solving the problems of energy consumption and environmental pollution in various aspects. Nowadays, the electric capacity of battery pack and the number of battery modules in new energy vehicles are gradually increasing, and the heat released from the power battery pack is also greatly increased.
The application of new energy vehicle power battery cooling technology can further extend the service life of the battery and effectively ensure the safety of the battery pack. Therefore, in the process of designing the battery cooling system of new energy vehicle power battery, it is necessary to flexibly apply air battery cooling technology, liquid battery cooling technology, heat pipe battery cooling technology and phase change material battery cooling technology to pay attention to the thermal management of power battery and promote the sustainable development of new energy vehicles.