A cooling system and control method

Abstract

This application relates to the field of vehicle power battery temperature control, and particularly to a cooling system and control method. The cooling system includes a cooling assembly, comprising a cold plate, a cell assembly, and a controller. The controller is configured to, upon detecting that the maximum temperature of the cell assembly exceeds a first threshold at a first moment, increase the opening of a first target valve corresponding to the location of the maximum temperature at the first moment by a first value; wherein the first target valve is either a first valve or a second valve; upon detecting a temperature drop in the cell assembly at a second moment after the first moment, based on the temperature difference between the maximum and minimum temperatures of the cell assembly at the second moment, decrease the opening of the first target valve by a second value at least once to control the temperature difference of the cell assembly to not exceed a preset threshold; the second value is less than the first value.

Description

Technical Field

[0001] This application relates to the field of vehicle power battery temperature control, and more particularly to a cooling system and control method. Background Technology

[0002] With the rapid development of the new energy vehicle industry, the capacity and charge / discharge rate of power batteries are also gradually increasing. The high heat generation and excessive temperature differences between cells caused by high-rate charging and discharging have become pain points in battery thermal management. If not properly controlled, this can lead to accelerated battery life degradation, limited power, and even fire. Cold plates are typically used to cool the cells. However, conventional technologies, including the arrangement of cells and cold plates, the structure of the cold plates, and common control methods, are insufficient to meet heat dissipation requirements and cannot effectively control battery temperature. Summary of the Invention

[0003] One objective of this invention is to provide a cooling system that can improve the heat exchange capacity of a cold plate; another objective is to provide a control method.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This application provides a cooling system, characterized in that it is applied to a vehicle and includes: A cooling assembly includes a cold plate, a first valve, and a second valve. The cold plate is welded from an upper plate, a middle plate, and a lower plate. A first corrugated flow channel extending along the length of the cold plate is provided between the upper plate and the middle plate, and a second corrugated flow channel extending along the length of the cold plate is provided between the lower plate and the middle plate. The inlet of the first corrugated flow channel is located at the first end of the upper plate and is connected to the first valve, and the outlet is located at the second end of the upper plate opposite to the first end. The inlet of the second corrugated flow channel is located at the second end of the lower plate and is connected to the second valve, and the outlet is located at the first end of the lower plate opposite to the second end. The battery cell assembly includes an upper row of battery cells and a lower row of battery cells stacked alternately on the upper and lower sides of a cold plate; the upper row of battery cells is located in a first arc groove on the upper plate, and the lower row of battery cells is located in a second arc groove on the lower plate; in the length direction, the first arc groove and the second arc groove are arranged alternately; wherein, a row of battery cells includes at least one row of multiple cylindrical battery cells arranged horizontally in sequence along the length direction; The controller is configured to, upon detecting that the maximum temperature of the battery cell assembly exceeds a first threshold at a first moment, increase the opening of a first target valve corresponding to the location of the maximum temperature at the first moment by a first value; wherein the first target valve is either a first valve or a second valve; upon detecting that the temperature of the battery cell assembly decreases at a second moment after the first moment, based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly at the second moment, decrease the opening of the first target valve by a second value at least once to control the temperature difference of the battery cell assembly to not exceed a preset threshold; the second value is less than the first value.

[0005] In this application, battery cell modules are staggered on the upper and lower plates of a cold plate, which includes two counter-flow channels to enhance its heat exchange capacity. Furthermore, a two-stage adjustment method distributes a large flow rate of coolant to the high-temperature area for rapid cooling, while simultaneously regulating temperature uniformity during the cooling process. This reduces the temperature difference between the cells, mitigating the charging and discharging power limitations caused by large temperature differences, thus slowing down battery pack degradation and extending its service life.

[0006] In some embodiments, the cooling system further includes a heat exchanger and a circulating pump; the inlet of the circulating pump is connected to the heat exchanger, and the outlet of the circulating pump is connected to the inlets of the first corrugated flow channel and the second corrugated flow channel; the circulating pump is used to deliver coolant to the cold plate assembly; the inlet of the heat exchanger is connected to the outlets of the first corrugated flow channel and the second corrugated flow channel, and the outlet of the heat exchanger is connected to the circulating pump; the heat exchanger is used to exchange heat with the coolant output from the cooling assembly.

[0007] In this application, the cooling system is equipped with a heat exchanger and a circulating pump. The circulating pump provides circulation power for the coolant, driving the coolant to flow continuously within the heat exchange loop. The heat exchanger efficiently absorbs and removes the heat generated by the battery cell assembly. The two work together to quickly achieve heat exchange, meeting the heat exchange regulation requirements of the battery cell under different temperature conditions, effectively suppressing the temperature rise of the battery cell, ensuring the stable operating temperature of the battery module, and improving the control reliability and safety of the thermal management system.

[0008] In some embodiments, the controller is also used to adjust the operating speed of the circulating pump and / or the heat exchange capacity of the heat exchanger based on the temperature of the cell assembly.

[0009] In this application, the controller is also used to adjust the operating speed of the circulating pump and / or the heat exchange capacity of the heat exchanger based on the temperature of the battery cell assembly. For example, when the temperature of the battery cell assembly is high, the operating speed of the circulating pump and / or the heat exchange capacity of the heat exchanger is increased; when the temperature of the battery cell assembly is low, the operating speed of the circulating pump and / or the heat exchange capacity of the heat exchanger is reduced, while taking into account both heat dissipation and energy consumption.

[0010] This application provides a control method applied to a cooling system in a vehicle. The method includes: identifying that the maximum temperature of the battery cell assembly exceeds a first threshold at a first moment, and increasing the opening of a first target valve corresponding to the location of the maximum temperature at the first moment by a first value; wherein the first target valve is a first valve or a second valve; identifying that the temperature of the battery cell assembly decreases at a second moment after the first moment, and based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly at the second moment, decreasing the opening of the first target valve by a second value at least once to control the temperature difference of the battery cell assembly to not exceed a preset threshold; the second value is less than the first value.

[0011] This application uses a two-stage adjustment method to distribute a large flow of coolant to the high-temperature area for rapid cooling, while simultaneously regulating the temperature during the cooling process. This reduces the temperature difference between the cells, improves the charging and discharging power limitations caused by large temperature differences between the cells, and can delay battery pack degradation and extend its service life.

[0012] In some embodiments, adjusting the opening of the first target valve to a second value at least once includes: gradually reducing the opening of the first target valve by the second value and re-acquiring the temperature difference between the maximum and minimum temperatures of the battery cell assembly after each adjustment, until the temperature difference is obtained to be no greater than a preset threshold and then the adjustment is stopped.

[0013] This application aims to control the temperature difference between the maximum and minimum temperatures of the battery cell assembly below a preset threshold. By slightly reducing the opening of the first target valve, the flow rate of the coolant in the corresponding flow channel can be gradually reduced. The adjustment process is gentle and smooth, without causing drastic fluctuations in cooling intensity, effectively reducing the overall temperature difference of the battery cell, improving the temperature uniformity and control accuracy of the battery cell, and achieving refined temperature control.

[0014] In some embodiments, increasing the opening of the first target valve corresponding to the location of the maximum temperature at the first moment by a first value includes: increasing the opening of the first target valve by a first value and decreasing the opening of the second target valve by a third value; the second target valve is a valve other than the first target valve among the first valve and the second valve; decreasing the opening of the first target valve by a second value at least once includes: decreasing the opening of the first target valve by a second value at least once and increasing the opening of the second target valve by a fourth value; the fourth value is less than the third value.

[0015] In order to quickly and efficiently reduce the temperature of local areas of the battery cell assembly, this application can not only increase the opening of the first target valve corresponding to the high temperature area, but also decrease the opening of the second target valve corresponding to the low temperature area, so that the coolant is concentratedly distributed to the pipeline corresponding to the high temperature area, significantly increasing the coolant flow rate of the pipeline and achieving rapid and substantial cooling.

[0016] In some embodiments, adjusting the opening of the first target valve to a second value at least once and adjusting the opening of the second target valve to a fourth value at least once includes: gradually decreasing the opening of the first target valve with the second value and gradually increasing the opening of the second target valve with the fourth value, and re-acquiring the temperature difference between the maximum and minimum temperatures of the battery cell assembly after each adjustment until the temperature difference is obtained is not greater than a preset threshold and the adjustment is stopped.

[0017] This application aims to control the temperature difference between the maximum and minimum temperatures of the battery cell assembly below a preset threshold. By slightly reducing the opening of the first target valve and increasing the opening of the second target valve, the flow rate of the coolant in the corresponding flow channel can be gradually reduced. The adjustment process is gentle and smooth, without causing drastic fluctuations in cooling intensity, effectively reducing the overall temperature difference of the battery cell, improving the temperature uniformity and control accuracy of the battery cell, and achieving refined temperature control.

[0018] In some embodiments, the first value and / or the third value correspond to the temperature range in which the maximum temperature is located; wherein, the higher the temperature range, the larger the corresponding first value and / or the third value.

[0019] This application sets the opening adjustment amount of the first target valve and / or the second target valve according to the temperature range in which the maximum temperature of the battery cell is located. A small opening is used in the low temperature range to avoid cooling redundancy and energy waste; a large opening is used in the high temperature range to quickly increase the cooling flow and efficiently reduce the temperature, so as to achieve a precise match between the valve opening adjustment amount and the actual heating conditions.

[0020] In some embodiments, the method further includes: controlling the operating speed of the circulating pump based on the temperature range in which the maximum temperature is located at the first moment; the operating speed corresponds to the temperature range in which the maximum temperature is located; wherein, a higher temperature range corresponds to a higher operating speed.

[0021] This application adaptively matches the operating speed of the circulating pump with the heat generation of the battery cell assembly, taking into account the heat dissipation response speed, energy economy and cell temperature uniformity, thereby improving the stability and service life of the battery thermal management system.

[0022] In some embodiments, the method further includes: controlling the heat exchange capacity of the heat exchanger based on the temperature range in which the maximum temperature is located at the first moment; the heat exchange capacity corresponds to the temperature range in which the maximum temperature is located; wherein, a high temperature range corresponds to a high heat exchange capacity.

[0023] This application can adaptively match the heat exchange intensity according to the temperature of the battery cell assembly. In the high-temperature stage, it can rapidly enhance heat exchange, remove accumulated heat in time, effectively curb the continuous rise in temperature, and reduce the risk of overheating. In the low-temperature stage, it can reduce the heat exchange load, avoid excessive cooling, reduce energy consumption, and at the same time help maintain the overall temperature uniformity of the battery cell assembly, and improve the adaptive regulation capability and operational reliability of the thermal management system. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of a cooling system provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a cooling component provided in an embodiment of this application; Figure 3 This is an exploded view of a cold plate provided in an embodiment of this application; Figure 4 This is a cross-sectional view of a cold plate provided in an embodiment of this application; Figure 5 This is a stacked schematic diagram of a battery cell assembly provided in an embodiment of this application; Figure 6 This is a stacking schematic diagram of another battery cell assembly provided in an embodiment of this application; Figure 7 This is a flowchart illustrating a control method provided in an embodiment of this application; Figure 8 This is a flowchart illustrating another control method provided in an embodiment of this application; Figure 9 This is a schematic diagram of the structure of a control device provided in an embodiment of this application; Figure 10 This is a schematic diagram of the structure of a control device provided in an embodiment of this application. Detailed Implementation

[0025] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0026] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0027] With the rapid development of the new energy vehicle industry, the capacity and charge / discharge rate of power batteries are also gradually increasing. The high heat generation and excessive temperature differences between cells caused by high-rate charging and discharging have become pain points in battery thermal management. If not properly controlled, this can lead to accelerated battery life degradation, limited power, and even fire. Cold plates are typically used to cool the cells. In conventional technology, cells are stacked on the cold plate, i.e., the cold plate is placed at the bottom of the cells. This arrangement is insufficient to meet heat dissipation requirements. Furthermore, conventional technology lacks precise control methods to effectively manage battery temperature.

[0028] Therefore, embodiments of this application provide a cooling system and control method. The cooling system is used to cool battery cell components in a vehicle and consists of a cold plate, battery cell components, and a controller. The battery cell components are stacked alternately on the upper and lower plates of the cold plate, which includes two counter-flow channels to improve the heat exchange capacity of the cold plate.

[0029] In this embodiment, the controller can adjust the opening of the coolant inlet valve, such as the first valve or the second valve, in the cold plate based on the temperature of the battery cell assembly. Specifically, when the maximum temperature of the battery cell assembly exceeds the limit, the opening of the valve corresponding to the location of the maximum temperature, i.e., the first target valve, is significantly increased to quickly reduce the temperature and avoid overheating in local areas. After determining that the temperature of the battery cell assembly has dropped, the opening of the first target valve is gradually reduced based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly to control the temperature difference of the battery cell assembly within a preset range. Through this two-stage adjustment method, a large flow of coolant is allocated to the high-temperature area for rapid cooling, while temperature uniformity is adjusted during the temperature reduction process. This reduces the temperature difference between the battery cells, improves the charging and discharging power limitation caused by large temperature differences, delays battery pack degradation, and extends service life. The two-stage control method provided in this embodiment breaks through the conventional approach of adjusting the opening only based on a single point temperature in the prior art, taking into account both rapid cooling at high temperatures and uniform temperature across the entire area, overcoming the shortcomings of the prior art that are prone to local overcooling and excessive temperature differences.

[0030] The following describes a cooling system and control method provided by an embodiment of this application, with reference to the accompanying drawings and embodiments. Figure 1 This is a schematic diagram of a cooling system provided in an embodiment of this application. Figure 1 As shown, the cooling system 100 includes a cooling assembly 1, a cell assembly 2, and a controller 3. Optionally, the cooling system 100 may also include a circulation pump 4 and a heat exchanger 5. The cooling system 100 is placed horizontally within the vehicle's battery pack housing.

[0031] Figure 2 This is a schematic diagram of a cooling assembly provided in an embodiment of this application. (As shown...) Figure 2 As shown, the cooling assembly 1 includes a cold plate 11. Figure 2 The cooling assembly 1 shown includes three cold plates 11 arranged side by side.

[0032] like Figure 3 This is an exploded view of the cold plate provided in the embodiments of this application in the vertical direction, such as... Figure 3 As shown, the cold plate 11 includes an upper plate 111, a middle plate 112, and a lower plate 113. The cold plate 11 is formed by welding the upper plate 111, the middle plate 112, and the lower plate 113. In other words, the cold plate 11 consists of three layers: upper, middle, and lower. All three layers of the cold plate are made of aluminum sheet by stamping and then welded together to form the final cold plate.

[0033] In this embodiment, the upper plate 111 has a top liquid inlet 114 and a top liquid outlet 115 at both ends along its length. The lower plate 113 has a bottom liquid inlet 116 and a bottom liquid outlet 117 at both ends along its length. Figure 4 As shown in the cross-sectional view of the cold plate 11, a first corrugated flow channel 118 extending along the length of the cold plate 11 is provided between the upper plate 111 and the middle plate 112, and a second corrugated flow channel 119 extending along the length of the cold plate 11 is provided between the middle plate 112 and the lower plate 113. The corrugated flow channel refers to a flow channel that is wavy in the thickness direction (i.e., the direction of gravity) of the cold plate 11, and the entire flow channel extends along the length of the cold plate 11. The first corrugated flow channel 118 and the second corrugated flow channel 119 are staggered. Figure 4 As shown, the corrugated protrusions, crests and troughs of the first corrugated channel 118 and the second corrugated channel 119 are staggered vertically.

[0034] In this embodiment, the inlet of the first corrugated flow channel 118 is located at the first end of the upper plate 111 and communicates with the first valve 12, while the outlet is located at the second end of the upper plate 111. The inlet of the second corrugated flow channel 119 is located at the second end of the lower plate 113 and communicates with the second valve 13, while the outlet is located at the first end of the lower plate 113. Specifically, the top liquid inlet 114 on the cold plate 11 is the inlet of the first corrugated flow channel 118, and the top liquid outlet 115 is the outlet of the first corrugated flow channel 118. The bottom liquid inlet 116 on the cold plate 11 is the inlet of the second corrugated flow channel 119, and the bottom liquid outlet 117 is the outlet of the second corrugated flow channel 119. This allows for the formation of counter-flow channels.

[0035] The first valve 12 can be a top-inlet electronic expansion valve, and the second valve 13 can be a bottom-inlet electronic expansion valve. The first valve 12 is used to control the flow rate of coolant entering the first corrugated flow channel 118. The second valve 13 is used to control the flow rate of coolant entering the second corrugated flow channel 119.

[0036] like Figure 2As shown, the top inlet 114 is connected to the top inlet pipe 120, and the top outlet 115 is connected to the top outlet pipe 122. The top inlet pipe 120 is equipped with a first valve 12. The bottom inlet 116 is connected to the bottom inlet pipe 121, and the bottom outlet 117 is connected to the bottom outlet pipe 123. The bottom inlet pipe 121 is equipped with a second valve 13. The top inlet pipe 120 and the bottom inlet pipe 121 are connected to the inlet distribution chamber 124, through which the coolant flowing into the cooling assembly is distributed. The bottom outlet pipe 123 and the top outlet pipe 122 are connected to the outlet distribution chamber 125, through which the coolant flowing out of the cooling assembly is collected. Specifically, the coolant enters the liquid distribution chamber 124 from the inlet and flows to the top liquid inlet pipe 120 and the bottom liquid inlet pipe 121. After passing through the electronic expansion valves 12 and 13, it is connected to the quick connector through the parallel branch pipe. Finally, it is connected to the three cold plates 11 through the quick connector. It flows into the cold plate channels 119 and 118 from the top liquid inlet 114 and the bottom liquid inlet 116 respectively, and finally flows out from the top liquid outlet 115 and the bottom liquid outlet 117 of the cold plate, completing a complete flow closed loop, carrying away the cell temperature and achieving the cooling of the battery pack.

[0037] like Figure 5 As shown, the battery cell assembly 2 includes an upper row of battery cells 201 and a lower row of battery cells 202 stacked alternately. The upper row of battery cells 201 is located in a first arcuate groove on the upper plate 111, and the lower row of battery cells 202 is located in a second arcuate groove on the lower plate 113. The first and second arcuate grooves are staggered along the length direction. The radii of the first and second arcuate grooves are greater than 1 / 4 of the battery cell circle. The staggered arrangement can be understood as the grooves being misaligned and not overlapping. A row of battery cells includes at least one row of multiple cylindrical battery cells arranged horizontally along the length direction. Figure 6 As shown, the upper row of battery cells 201 and the lower row of battery cells 202 include three rows of cylindrical battery cells arranged horizontally along the length direction. Specifically, the battery cell assembly 2 is arranged vertically within the arc of the upper plate 111 and the lower plate 113 of the cold plate 11, and exchanges heat with the cold plate 11 through thermally conductive adhesive. For example, Figure 5 As shown, the cold plate is made of three layers of plates, upper, middle and lower, welded together. The battery cells are arranged on both sides of the upper and lower plates, and the coolant flows in layers.

[0038] like Figure 4As shown, by changing the distances S1, S2, S3, and S4 between the middle plate 112 and the upper plate 111 and lower plate 113 of the cold plate at the cell location, the flow rate and flow state of the coolant at the cell location can be increased, thereby improving the heat exchange capacity of the coolant and enhancing the heat exchange capacity of the cold plate at the flow design level of the cooling system. For example, S4 is greater than S2, and S3 is greater than S1. That is, the vertical distance S1 from the contact point between the upper row of cells and the upper plate 111 to the middle plate 112 is less than the vertical distance S3 from the corresponding position on the lower plate 112 to the middle plate 112. Similarly, the vertical distance S2 from the contact point between the lower row of cells and the lower plate 113 to the middle plate 112 is less than the vertical distance S4 from the corresponding position on the upper plate 111 to the middle plate 112. This structural design results in smaller fluid spaces and more compact flow channel gaps on both the upper and lower battery cell sides, effectively increasing the flow velocity of the coolant around the battery cells. At the same time, the asymmetrical spacing layout can change the flow direction and flow field distribution of the cooling medium, optimize the fluid flow state, enhance fluid disturbance and turbulence, and strengthen convective heat transfer efficiency.

[0039] In some embodiments, the circulating pump 4 is used to deliver coolant to the cold plate assembly 1. The inlet of the circulating pump 4 is connected to the outlet of the heat exchanger 5 to receive the coolant output from the heat exchanger 5, and the outlet of the circulating pump 4 is connected to the inlets of the first corrugated flow channel 118 and the second corrugated flow channel 119 to deliver coolant to the first corrugated flow channel 118 and the second corrugated flow channel 119. For example, the outlet of the circulating pump 4 is connected to the first corrugated flow channel 118 through the top inlet pipe 120 and the first valve 12, and to the second corrugated flow channel 119 through the bottom inlet pipe 121 and the second valve 13.

[0040] In some embodiments, the heat exchanger 5 is used to exchange heat with the coolant output from the cooling assembly 1. Exemplarily, the inlet of the heat exchanger 5 is connected to the outlet of the first corrugated channel 118 and the outlet of the second corrugated channel 119, for receiving the coolant output from the cooling assembly 1. The outlet of the heat exchanger 5 is connected to the inlet of the circulating pump 4, for inputting the heat-exchanged coolant into the circulating pump 4.

[0041] In some embodiments, controller 3 may be, for example, a controller or control unit in a vehicle. Controller 3 is used to adjust the opening degree of the first valve and / or the second valve based on the temperature of the battery cell assembly. Controller 3 is also used to adjust the operating speed of the circulating pump and / or the heat exchange capacity of the heat exchanger based on the temperature of the battery cell assembly. Exemplarily, controller 3 is used to execute a control method provided in an embodiment of this application.

[0042] Figure 7 This is a flowchart illustrating a control method provided in an embodiment of this application. The method includes: S1, if the maximum temperature of the battery cell assembly exceeds the first threshold at the first moment, the opening of the first target valve corresponding to the location of the maximum temperature at the first moment will be increased by the first value.

[0043] In this embodiment of the application, when the controller detects that the maximum temperature of the battery cell assembly exceeds the standard at a certain moment, such as at the first moment, the controller can significantly open the valve corresponding to the location of the maximum temperature, such as the first target valve, to quickly cool down the battery cell assembly and prevent the temperature of a local area from exceeding the standard.

[0044] In some embodiments, the controller can acquire the temperature of the battery cell assembly, such as battery cell assembly 2, using temperature sensors. For example, multiple temperature sensors can be deployed in the battery cell assembly. For instance, multiple temperature sensors can be deployed on the upper surface of the upper row of battery cells 201, the lower surface of the lower row of battery cells 202, the top liquid inlet pipe 120, the bottom liquid inlet pipe 121, the bottom liquid outlet pipe 123, and the top liquid outlet pipe 122. The controller can periodically acquire multiple temperatures of the battery cell assembly collected by the multiple temperature sensors. The controller takes the maximum value among the multiple temperatures as the maximum temperature of the battery cell assembly at the current sampling time, and the minimum value among the multiple temperatures as the minimum temperature of the battery cell assembly at the current sampling time. After acquiring the maximum temperature at each sampling time, the controller can compare the maximum temperature with a first threshold. If the maximum temperature of the battery cell assembly at a certain sampling time exceeds the first threshold, the controller determines that the maximum temperature of the battery cell assembly at that sampling time, i.e., the first time, exceeds the first threshold.

[0045] In some embodiments, the first threshold is a preset maximum allowable temperature. A maximum temperature exceeding the first threshold indicates that the temperature in a localized area of ​​the battery cell assembly is excessive. In this case, the controller can significantly increase the opening of the first target valve corresponding to the location of the maximum temperature. This can be understood as the first target valve controlling the flow rate of coolant at the location of the maximum temperature. For example, the first target valve is either a first valve or a second valve. For instance, if the maximum temperature at a first moment occurs at the upper row of battery cells, the first target valve is the first valve 12. Or, for another example, if the maximum temperature at a first moment occurs at the lower row of battery cells, the first target valve is the second valve 13.

[0046] In some embodiments, the controller increases the opening of the first target valve. Specifically, the controller increases the opening of the first target valve by a first value, such as a percentage, like 10% or 20%. For example, if the initial opening of the first target valve is 50%, the controller adjusts the opening of the first target valve to 60%, 70%, or 80%. After increasing the opening of the first target valve, the flow rate of coolant entering the flow channel corresponding to the maximum temperature increases rapidly, achieving rapid cooling. Specifically, if the maximum temperature at the first moment occurs at the upper row of battery cells, the flow channel corresponding to the maximum temperature is the first corrugated flow channel 118; if the maximum temperature at the first moment occurs at the lower row of battery cells, the flow channel corresponding to the maximum temperature is the second corrugated flow channel 119.

[0047] In some embodiments, the first value is related to the temperature range in which the maximum temperature at the first moment falls. For example, the higher the temperature range in which the maximum temperature at the first moment falls, the larger the first value. For example, the temperature range may include a first temperature range, a second temperature range, and a third temperature range. The first temperature range is greater than or equal to a first threshold and less than a second threshold. The second temperature range is greater than or equal to the second threshold and less than a third threshold. The third temperature range is greater than or equal to the third threshold. Wherein, the first threshold is less than the second threshold, and the second threshold is less than the third threshold. For example, the first threshold is 40°C, the second threshold is 50°C, and the third threshold is 60°C. The first value corresponding to the first temperature range may be, for example, 10%, the second value corresponding to the second temperature range may be, for example, 15%, and the third value corresponding to the third temperature range may be, for example, 20%. That is, the higher the maximum temperature at the first moment, the larger the opening adjustment amount of the first target valve, i.e., the first value. When the maximum temperature is in the low-temperature range, the opening adjustment amount of the first target valve is smaller, and when the maximum temperature is in the high-temperature range, the opening adjustment amount of the first target valve is larger. This application sets the opening adjustment of the first target valve according to the temperature range in which the maximum temperature of the battery cell is located. A small opening is used in the low-temperature range to avoid cooling redundancy and energy waste; a large opening is used in the high-temperature range to quickly increase the cooling flow and achieve efficient cooling. This achieves a precise match between the opening adjustment of the first target valve and the actual heating conditions. By adopting a gradient control method, it takes into account both energy consumption control under low-temperature conditions and heat dissipation response speed under high-temperature conditions. This not only prevents the expansion of the battery cell temperature difference caused by overcooling, but also effectively avoids the risk of local overheating, improving the overall temperature control stability and operational safety of the battery cell assembly.

[0048] In this embodiment, before adjusting the opening of the first target valve, the controller can first determine a suitable first value based on the maximum temperature at a first moment. For example, the controller determines the suitable first value based on a pre-stored first mapping relationship. This first mapping relationship characterizes the one-to-one correspondence between multiple temperature ranges and multiple first values. For example, the first mapping relationship could be that the first value corresponding to the first temperature range is 10%, the second value corresponding to the second temperature range is 15%, and the third value corresponding to the third temperature range is 20%.

[0049] It should be understood that in this embodiment of the application, the controller continuously monitors the temperature of the battery cell assembly. After executing S1, the controller will continue to acquire the temperature of the battery cell assembly and determine whether the temperature of the battery cell assembly has dropped based on the acquired temperature. If it is determined that the temperature of the battery cell assembly has dropped, the controller can execute S2.

[0050] S2, after the first moment, a temperature drop in the battery cell assembly is detected in the second moment. Based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly in the second moment, the opening of the first target valve is reduced by a second value at least once to control the temperature difference of the battery cell assembly to not exceed a preset threshold.

[0051] In this embodiment, the controller detects a temperature drop in the battery cell assembly at a second time point after the first time point, and determines to enter the temperature equalization control stage. The second time point could be, for example, the 5th second after the first time point, or the 10th second after the first time point, which will not be elaborated further. For example, after executing S1, the controller determines whether the temperature of the battery cell assembly has dropped based on the maximum temperature of the battery cell assembly at the 5th second after the first time point. If the maximum temperature at the 5th second is not less than the maximum temperature at the first time point, the controller determines that the temperature of the battery cell assembly has not dropped. Then, the controller can determine whether the temperature of the battery cell assembly has dropped based on the maximum temperature at the 10th second, until a temperature drop in the battery cell assembly is detected. Alternatively, if the maximum temperature at the 5th second is less than the maximum temperature at the first time point, the controller detects a temperature drop in the battery cell assembly. In other words, the second time point is the time point at which the temperature drop of the battery cell assembly is detected after a significant increase in the opening of the first target valve, and the second time point is after the first time point.

[0052] In some embodiments, the temperature equalization control stage may involve the controller adjusting the opening of a first target valve based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly, until the temperature difference between the battery cell assemblies is controlled within a preset range. For example, based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly at a second time, the controller may at least once reduce the opening of the first target valve by a second value to control the temperature difference between the battery cell assemblies to be no greater than a preset threshold. The second value is less than the first value, such as 1%, 2%, or 5%. The preset threshold is a pre-set average temperature value used to control the temperature equalization of the battery cell assembly. The preset threshold may be, for example, 3°C, 5°C, or 6°C. It should be understood that the specific values ​​of the second value and the preset threshold can be designed as needed.

[0053] For example, the controller gradually reduces the opening of the first target valve according to the second value, and after each reduction, it re-acquires the temperature difference between the maximum and minimum temperatures of the battery cell assembly until a temperature difference not exceeding a preset threshold is obtained, at which point the adjustment stops. Taking a second value of 5%, and after executing S1, the opening of the first target valve is adjusted to 70%, for example, the controller reduces the opening of the first target valve by 5%, e.g., to 65%. After a preset time from the adjustment time, it re-acquires the temperature difference between the maximum and minimum temperatures of the battery cell assembly and determines whether this temperature difference is less than the preset threshold. If the temperature difference is less than the preset threshold, the adjustment stops. If the temperature difference is not less than the preset threshold, the controller again reduces the opening of the first target valve by 5%, e.g., to 60%. Then, after a preset time from the second adjustment time, it re-acquires the temperature difference between the maximum and minimum temperatures of the battery cell assembly and determines whether this temperature difference is less than the preset threshold. If the temperature difference is less than the preset threshold, the adjustment stops. If the temperature difference is not less than the preset threshold, the controller reduces the opening of the first target valve by 5%, such as to 55%. Then, the controller determines whether the temperature difference between the battery cell components is less than the preset threshold, and so on, until the temperature difference between the maximum and minimum temperatures of the battery cell components is controlled below the preset threshold. The preset duration can be, for example, 5 seconds, 10 seconds, 15 seconds, or 20 seconds, and its value can be designed as needed.

[0054] As can be seen, the control method provided in this application embodiment, when the local temperature of the battery cell assembly exceeds the standard, significantly increases the opening of the corresponding valve to allow more coolant to flow in and quickly reduce the temperature of the local area. Then, after determining that the temperature of the local area has dropped, the opening of the corresponding valve is gradually reduced in small increments with the goal of controlling the temperature difference of the battery cell assembly, so as to control the temperature of the battery cell assembly within a preset range.

[0055] In the example shown above, when the local temperature of the battery cell assembly exceeds the limit, simply increasing the opening of the first target valve can increase the flow rate of the coolant in the channel corresponding to the high-temperature area. However, since the two inlet pipes are connected in parallel, increasing the opening of only one valve does not change the flow resistance of the other inlet pipe, which continues to divert coolant. Therefore, it can only slightly increase the flow rate of the coolant in the corresponding inlet pipe. To address this, in some embodiments, a linkage adjustment method can be used, such as increasing the opening of the valve corresponding to the high-temperature area while decreasing the opening of the valve corresponding to the low-temperature area. By changing the flow resistance of the pipes on both sides, the coolant is concentrated in the pipe corresponding to the high-temperature area, significantly increasing the coolant flow rate and achieving rapid and substantial cooling.

[0056] For example, S1 can be replaced by: recognizing that the maximum temperature of the battery cell assembly exceeds a first threshold at a first moment, increasing the opening of the first target valve corresponding to the location of the maximum temperature at the first moment by a first value, and decreasing the opening of the second target valve by a third value. Specifically, the controller recognizes that the maximum temperature of the battery cell assembly exceeds the first threshold at a first moment, and can increase the opening of the first target valve by a first value and decrease the opening of the second target valve by a third value. Here, the second target valve is the valve other than the first target valve among the first and second valves. If the first target valve is the first valve, then the second target valve is the second valve. If the first target valve is the second valve, then the second target valve is the first valve.

[0057] The third value can be a percentage, such as 10% or 20%. For example, if the initial opening of the first and second target valves is 50%, the controller can adjust the opening of the first target valve to 60%, 70%, or 80%, and the opening of the second target valve to 40%, 30%, or 20%. The purpose of this is to reduce the flow rate of coolant entering the flow channel corresponding to the low-temperature region and increase the flow rate of coolant entering the flow channel corresponding to the high-temperature region, thereby achieving rapid cooling.

[0058] In some embodiments, the third value is related to the temperature range in which the maximum temperature at the first moment falls. For example, the higher the temperature range in which the maximum temperature at the first moment falls, the larger the third value. For example, the temperature range may include a first temperature range, a second temperature range, and a third temperature range. The first temperature range is greater than or equal to a first threshold and less than a second threshold. The second temperature range is greater than or equal to the second threshold and less than a third threshold. The third temperature range is greater than or equal to the third threshold. Wherein, the first threshold is less than the second threshold, and the second threshold is less than the third threshold. For example, the first threshold is 40°C, the second threshold is 50°C, and the third threshold is 60°C. The third value corresponding to the first temperature range may be, for example, 10%, the second value corresponding to the second temperature range may be, for example, 15%, and the third value corresponding to the third temperature range may be, for example, 20%. That is, the higher the maximum temperature at the first moment, the larger the opening adjustment of the second target valve. When the maximum temperature is in a low temperature range, the opening adjustment of the second target valve is smaller, and when the maximum temperature is in a high temperature range, the opening adjustment of the second target valve is larger. This application sets the opening adjustment amount of the second target valve according to the temperature range where the maximum temperature of the battery cell is located. A small opening is used in the low temperature range to avoid excessive flow in the flow channel corresponding to the high temperature range, which would cause cooling redundancy and energy waste. A large opening is used in the high temperature range to increase the flow in the flow channel corresponding to the high temperature range, thereby achieving efficient cooling. This approach can balance energy consumption control under low temperature conditions and heat dissipation response speed under high temperature conditions. It can prevent the expansion of the temperature difference of the battery cell caused by overcooling and effectively avoid the risk of local overheating, thereby improving the overall temperature control stability and operational safety of the battery cell assembly.

[0059] In this embodiment, before adjusting the valve opening, the controller can first determine suitable first and third values ​​based on the maximum temperature at a first moment. For example, the controller determines the suitable first value based on a pre-stored first mapping relationship, which is as described above and will not be repeated. The controller determines the suitable third value based on a pre-stored second mapping relationship. This second mapping relationship is used to characterize the one-to-one correspondence between multiple temperature ranges and multiple third values. For example, the first mapping relationship could be that the third value corresponding to the first temperature range is 10%, the second value corresponding to the second temperature range is 15%, and the third value corresponding to the third temperature range is 20%.

[0060] For example, S2 can be replaced by: recognizing a temperature drop in the cell assembly at a second time after the first time, and based on the temperature difference between the maximum and minimum temperatures of the cell assembly at the second time, at least once decreasing the opening of the first target valve by a second value and increasing the opening of the second target valve by a fourth value.

[0061] For example, based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly at a second time, the controller at least once reduces the opening of the first target valve by a second value and increases the opening of the second target valve by a fourth value to control the temperature difference of the battery cell assembly to not exceed a preset threshold. The fourth value is less than the third value, such as 1%, 2%, or 5%.

[0062] For example, the controller gradually decreases the opening of the first target valve according to the second value and gradually increases the opening of the second target valve according to the fourth value. After each adjustment, the controller re-acquires the temperature difference between the maximum and minimum temperatures of the battery cell assembly until the temperature difference is no greater than a preset threshold, at which point the adjustment stops. For instance, if the second and fourth values ​​are 5%, and after executing S1 the opening of the first target valve is adjusted to 70% and the second target valve to 30%, the controller first decreases the opening of the first target valve by 5%, e.g., to 65%, and increases the opening of the second target valve by 5%, e.g., to 35%. After a preset time from the adjustment time, the controller again acquires the temperature difference between the maximum and minimum temperatures of the battery cell assembly and determines whether this temperature difference is less than a preset threshold. If the temperature difference is less than the preset threshold, the adjustment stops. If the temperature difference is not less than the preset threshold, the controller again reduces the opening of the first target valve by 5%, for example, to 60%, and increases the opening of the second target valve by 5%, for example, to 40%. Then, after a preset time from the second adjustment, the temperature difference between the maximum and minimum temperatures of the battery cell assembly is acquired again, and the controller determines whether this temperature difference is less than the preset threshold. If the temperature difference is less than the preset threshold, the adjustment stops. If the temperature difference is not less than the preset threshold, the controller again reduces the opening of the first target valve by 5%, for example, to 55%, and increases the opening of the second target valve by 5%, for example, to 45%. Then the controller determines whether the temperature difference between the battery cell assemblies is less than the preset threshold, and so on, until the temperature difference between the maximum and minimum temperatures of the battery cell assembly is controlled below the preset threshold, and the adjustment stops. The preset time can be, for example, 5 seconds, 10 seconds, 15 seconds, or 20 seconds, and its value can be designed as needed.

[0063] In some embodiments, the controller can also adjust the operating speed of the circulation pump based on the temperature range containing the maximum temperature at the first moment. For example, the operating speed of the circulation pump is related to the temperature range containing the maximum temperature at the first moment. For instance, the higher the temperature range containing the maximum temperature at the first moment, the higher the operating speed of the circulation pump. For example, the temperature range may include temperature range 1, temperature range 2, temperature range 3, and temperature range 4. Temperature range 2 is less than a first threshold. Temperature range 2 is greater than or equal to the first threshold and less than a second threshold. Temperature range 3 is greater than or equal to the second threshold and less than a third threshold. Temperature range 4 is greater than or equal to the third threshold. The first threshold is less than the second threshold, and the second threshold is less than the third threshold. In this embodiment, the operating speed corresponding to temperature range 1 may be, for example, P1; the operating speed corresponding to temperature range 2 may be, for example, P2; the operating speed corresponding to temperature range 3 may be, for example, P3; and the operating speed corresponding to temperature range 4 may be, for example, P4. P1, P2, P3, and P4 increase sequentially. That is, the higher the maximum temperature at the first moment, the higher the operating speed of the circulation pump. Increasing the operating speed of the circulation pump under high-temperature conditions can significantly accelerate the coolant circulation rate, enhance the heat exchange efficiency of the cooling components, quickly suppress the temperature rise of the battery cells, and reduce the risk of localized overheating and thermal runaway. Under low-temperature conditions, it operates at a lower speed to reduce unnecessary power consumption and equipment wear, and avoid excessive cooling that could lead to increased temperature differences between the cells. This method adaptively matches the operating speed of the circulation pump with the heat generation of the battery cells, balancing heat dissipation response speed, energy economy, and cell temperature uniformity, thereby improving the stability and lifespan of the battery thermal management system.

[0064] In some embodiments, the controller can also adjust the heat exchanger's heat exchange capacity based on the temperature range containing the maximum temperature at the first moment. For example, the heat exchanger's heat exchange capacity is related to the temperature range containing the maximum temperature at the first moment. For instance, the higher the temperature range containing the maximum temperature at the first moment, the higher the heat exchanger's heat exchange capacity. For example, the temperature range may include temperature range 1, temperature range 2, temperature range 3, and temperature range 4, as detailed above. In this embodiment, the heat exchange capacity corresponding to temperature range 1 may be, for example, D1; the heat exchange capacity corresponding to temperature range 2 may be, for example, D2; the heat exchange capacity corresponding to temperature range 3 may be, for example, D3; and the heat exchange capacity corresponding to temperature range 4 may be, for example, D4. D1, D2, D3, and D4 increase sequentially. That is, the higher the maximum temperature at the first moment, the higher the heat exchanger's heat exchange capacity. The embodiments of this application can adaptively match the heat exchange intensity according to the temperature of the battery cell assembly. In the high-temperature stage, heat exchange is rapidly enhanced to remove accumulated heat in time, effectively curb the continuous rise in temperature, and reduce the risk of overheating. In the low-temperature stage, the heat exchange load is reduced to avoid excessive cooling and reduce energy consumption. At the same time, it helps to maintain the overall temperature uniformity of the battery cell assembly and improve the adaptive regulation capability and operational reliability of the thermal management system.

[0065] In this embodiment, the heat exchanger's heat exchange capacity can be dynamically adjusted by modifying its effective heat exchange area, the number of internal flow channels, and the cross-sectional area of ​​the refrigerant flow. Existing technologies are readily available and will not be elaborated upon further. In some embodiments, adjusting the heat exchanger's heat exchange capacity can specifically involve adjusting its subcooling. Subcooling refers to the temperature difference between the refrigerant's condensation into a saturated liquid in the heat exchanger and the temperature below the saturation temperature at the current pressure. Subcooling = Saturated condensation temperature - Actual liquid temperature. For example, the controller can adjust the subcooling by adjusting the cooling fan speed and / or the refrigerant temperature. Existing technologies are readily available and will not be elaborated upon further. The higher the temperature range containing the maximum temperature at the first moment, the higher the cooling capacity of the heat exchanger.

[0066] The following section introduces this solution in the context of specific application scenarios.

[0067] This application relates to a thermal management system for new energy vehicles, power batteries, or energy storage batteries, specifically to a cooling system and its control logic consisting of a circulating pump, a cold plate, a battery cooler, an electronic expansion valve, a battery management system (BMS) controller, a thermal management system (TMS), a compressor, a condenser, pipelines, etc.

[0068] With the continuous development of battery technology, the high heat generation and excessive temperature difference between cells caused by high-rate charging and discharging have become pain points in battery heat pipes. If not properly controlled, this can lead to accelerated battery life degradation, limited power, and even fire. Traditional liquid cooling plate solutions, placed at the bottom of the cell, are increasingly unable to meet the requirements. Some researchers have proposed large-area cooling and phase change cooling, but none of these solutions offer a simple and low-cost solution at the system flow level. Therefore, developing a cooling system with good cooling performance, simple process, and low cost remains an urgent problem to be solved in battery thermal management.

[0069] Related technology 1 proposes an integrated power battery cooling system, cooling control method, and electric vehicle. This invention designs a system scheme for integrated control of an air conditioning system and a power battery cooling system. It mainly adjusts the compressor speed and the superheat target of the electronic expansion valve based on the inlet and outlet temperatures of the cooler and data obtained from a third temperature sensor to achieve integrated control of the two systems. However, it does not optimize the cooling performance of the battery pack or the temperature uniformity between cells; it is merely an integration method for the two systems.

[0070] Related technology 2 proposes a liquid cooling plate, battery pack and vehicle. The cooling plate structure is divided into three parts: upper, middle and lower. The middle layer of the cooling plate has through holes in the flow channel area. The entire flow channel is a traditional U-shaped structure. The only difference is that an intermediate plate is added between the ordinary cooling plates, and the intermediate plate is designed with through holes. The main purpose is to solve the problem of thermal deformation of the battery cell.

[0071] Related technology 3 proposes a battery, power device and energy storage device, and designs a concave heat exchange plate. The battery cell is placed in the concave structure, and the two ends are liquid chambers. The coolant can enter and exit from opposite sides or from the same side, which increases the contact area between the battery cell and the cold plate, thereby enhancing the heat exchange capacity of the cold plate, but does not improve the temperature uniformity of the battery cell.

[0072] Related technology four proposes a heat dissipation plate and battery system, which adopts a three-layer plate to improve the heat exchange capacity of the battery pack and avoid local high temperature. The structure from the cell to the cold plate is as follows: flat plate: contacting the cell; blown plate: enclosed refrigerant for phase change heat exchange; liquid cooling plate: heat is exchanged through the flow of coolant. This patent only optimizes the heat exchange form of the cold plate and improves the heat exchange performance of the cold plate, but does not explain the process feasibility, cost and system control.

[0073] Related technology five proposes a liquid cooling system and battery pack. The key point of this invention patent is the design of a bottom-cooled cold plate structure, which is specifically divided into a liquid cooling plate and a liquid cooling pipe. The liquid cooling plate is used to undergo phase change and conduct heat from the battery cell. The liquid cooling pipe is used to exchange heat from the liquid cooling plate and transfer it to the outside through the coolant. This patent is still limited to improving the performance of the cold plate in a single aspect.

[0074] In summary, current efforts by researchers to improve battery pack cooling performance and cell temperature uniformity mainly focus on enhancing the heat exchange area and form of the cold plate, lacking system-level design capabilities such as internal flow within the cold plate, circulation pump control of heat exchanger performance, and electronic expansion valves and their opening.

[0075] This application designs a system control method for the inlet flow distribution ratio, the operating speed of the circulating pump, and the heat exchange capacity of the heat exchanger. By monitoring the real-time temperature range of the battery cells through a BMS, the method controls the electronic expansion valve, circulating pump, and heat exchanger to cool the battery pack. Simultaneously, it intelligently adjusts the opening ratio and switching time of the electronic expansion valve based on whether the cooling phase is underway and whether the temperature difference meets a preset threshold. Further, a sequential logic is designed. The first principle is to rapidly cool the battery by distributing a large proportion of the flow rate through the maximum temperature range. Specifically, the first principle flow rate is calculated and the operating speed of the circulating pump is selected based on the temperature difference between the minimum and maximum temperatures of the battery cells. Simultaneously, the flow rate ratio is selected based on the maximum battery cell temperature. When the temperature relationship between the first and fifth seconds is established, it is determined that the temperature is in the cooling phase. The second principle is then activated, finely adjusting the flow rate ratio and switching time until the temperature difference between the battery cells is less than the preset threshold, maintaining the flow rate distribution. The minimum battery cell temperature can be characterized by the coolant inlet temperature.

[0076] Figure 8 This is a schematic diagram of a control method provided in an embodiment of this application, such as... Figure 7 As shown, the method includes: S801, obtains the maximum temperature of the battery cell assembly at the first moment.

[0077] S802 determines whether the maximum temperature at the first moment is in the first temperature range, the second temperature range, or the third temperature range.

[0078] S803, if the maximum temperature at the first moment is in the first temperature range, the second temperature range, or the third temperature range, determine the first value, the second value, the target operating speed of the circulating pump, and the target heat exchange capacity of the heat exchanger.

[0079] For example, if the first threshold T1 ≤ the maximum temperature Tmax at the first moment < the second threshold T2, or the second threshold T2 ≤ the maximum temperature Tmax at the first moment < the third threshold T3, or the third threshold T3 ≤ the maximum temperature Tmax at the first moment, then based on a preset mapping relationship, the first value, the third value, the target operating speed, and the target heat exchange capacity are determined. For instance, if the first threshold T1 ≤ the maximum temperature Tmax at the first moment < the second threshold T2, then the first value and the third value are determined to be 10%, the target operating speed is P2, and the target heat exchange capacity is D2. If the second threshold T2 ≤ the maximum temperature Tmax at the first moment < the third threshold T3, then the first value and the third value are determined to be 15%, the target operating speed is P3, and the target heat exchange capacity is D3. If the third threshold T3 ≤ the maximum temperature Tmax at the first moment, then the first value and the third value are determined to be 20%, the target operating speed is P4, and the target heat exchange capacity is D4.

[0080] S804, increase the opening of the first target valve by a first value, decrease the opening of the second valve by a second value, control the operating speed of the circulating pump to the target operating speed, and control the heat exchanger's heat exchange capacity to the target heat exchange capacity.

[0081] For example, if the first threshold T1 ≤ the maximum temperature Tmax at the first moment < the second threshold T2, then the opening of the first target valve is increased by 10%, the opening of the second target valve is decreased by 10%, the operating speed of the circulating pump is controlled at P2, and the heat exchanger's heat exchange capacity is controlled at D2. As another example, if the second threshold T2 ≤ the maximum temperature Tmax at the first moment < the third threshold T3, then the opening of the first target valve is increased by 15%, the opening of the second target valve is decreased by 15%, the operating speed of the circulating pump is controlled at P3, and the heat exchanger's heat exchange capacity is controlled at D3. As yet another example, if the third threshold T3 ≤ the maximum temperature Tmax at the first moment, then the opening of the first target valve is increased by 20%, the opening of the second target valve is decreased by 20%, the operating speed of the circulating pump is controlled at P4, and the heat exchanger's heat exchange capacity is controlled at D4. Optionally, if the third threshold T3 is less than or equal to the maximum temperature Tmax at the first moment, the controller can also make a comprehensive judgment based on the preset power calibration table, the real-time battery thermal calculation results, and the ambient temperature parameters. Based on the judgment result, it can issue a vehicle power limiting command to limit the battery charging and discharging power and the vehicle's power output, ensuring safe battery operation. In other words, the third threshold T3 is the power limiting trigger temperature. If Tmax at the first moment is greater than or equal to the third threshold T3, the power limiting rapid cooling logic is entered, and cooling is performed at maximum capacity. Otherwise, the normal heat dissipation logic is entered, selecting the operating speed of the circulating pump and the heat exchanger's heat exchange capacity based on the range of Tmax at the first moment.

[0082] S805 determines whether the temperature of the battery cell assembly has dropped.

[0083] S806, if the temperature of the battery cell assembly drops, the opening of the first target valve is reduced by a second value, and the opening of the second target valve is increased by a third value.

[0084] For example, if a temperature drop in the battery cell assembly is detected, the controller will decrease the opening of the first target valve by 5% and increase the opening of the second target valve by 5%.

[0085] S807, determine whether the temperature difference ΔT is greater than the preset threshold.

[0086] After a preset time following the execution of S806, the controller again acquires the temperature difference ΔT between the maximum and minimum temperatures of the battery cell assembly. This temperature difference ΔT is then compared to a preset threshold. If the temperature difference ΔT is not greater than the preset threshold, adjustment stops. If the temperature difference ΔT is greater than the preset threshold, S806 is executed again until the temperature difference ΔT is no greater than the preset threshold, at which point adjustment stops. The opening degrees of the first target valve and the second target valve at the point of stopping adjustment are used as the final target opening degrees for the first and second target valves.

[0087] In this embodiment, after the BMS controller identifies the range and location of the maximum temperature, it adjusts the opening ratio of the electronic expansion valve through the TMS. First, it enters a large-ratio distribution stage for rapid cooling. Then, it determines whether Tmax is greater than or equal to Tmax-5 after 5 seconds. If the temperature relationship between Tmax and Tmax-5 after 5 seconds is valid, it enters the temperature difference adjustment stage. Otherwise, it determines whether Tmax is greater than or equal to Tmax-10 after 10 seconds. If the temperature relationship between Tmax and Tmax-10 after 10 seconds is valid, it enters the temperature difference adjustment stage. In the temperature difference adjustment stage, guided by controlling the temperature difference ΔT to be less than a preset threshold, the opening of the first target valve is gradually reduced by a small amount while the opening of the second target valve is increased until ΔT is less than the preset threshold, at which point the opening ratio of the electronic expansion valve is fixed.

[0088] S808, if the maximum temperature at the first moment is not in the first temperature range, the second temperature range, or the third temperature range, determine the target operating speed of the circulating pump and the target thermal capacity of the heat exchanger.

[0089] For example, if the maximum temperature Tmax at the first moment is less than the first threshold T1, the controller determines the target operating speed as P1 and the target heat exchange capacity as D1.

[0090] S809 controls the operating speed of the circulating pump to the target operating speed and the heat exchanger's heat exchange capacity to the target heat exchange capacity.

[0091] For example, if the maximum temperature Tmax at the first moment is less than the first threshold T1, then the operating speed of the circulating pump is controlled to P1, and the heat exchanger's heat exchange capacity is controlled to D1. In this embodiment, the opening degree of the first target valve and the opening degree of the second target valve can also be adjusted to a preset opening degree, such as 50%. That is, when the maximum temperature is less than the first threshold, the controller controls the opening degree of the first target valve and the opening degree of the second target valve to a preset opening degree, such as 50%, controls the operating speed of the circulating pump to P1, and controls the heat exchanger's heat exchange capacity to D1.

[0092] In other embodiments, the first threshold T1 is the cooling start temperature. When the maximum temperature is lower than the first threshold, the cooling system is not activated. For example, the first target valve and the second target valve are closed to cut off the cooling medium flow loop. At the same time, the circulating pump is shut down, and the heat exchanger stops working, thus exiting the cooling heat exchange mode. No heat dissipation is required under low-temperature conditions, so shutting down the cooling system avoids ineffective heat exchange, reduces energy consumption, and minimizes losses from frequent device start-stop cycles.

[0093] The following describes an embodiment of the device provided in this application with reference to the accompanying drawings. Figure 9 This is a schematic diagram of the structure of a control device provided in this application, such as... Figure 9 As shown, the control device 900 includes a first control unit 901 and a second control unit 902.

[0094] The first control unit 901 is used to identify that the maximum temperature of the battery cell assembly at a first moment exceeds a first threshold, and to increase the opening of the first target valve corresponding to the location of the maximum temperature at the first moment by a first value; wherein, the first target valve is a first valve or a second valve; The second control unit 902 is used to detect a temperature drop in the battery cell assembly at a second time after the first time. Based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly at the second time, the opening of the first target valve is reduced by a second value at least once to control the temperature difference of the battery cell assembly to be no greater than a preset threshold; the second value is less than the first value.

[0095] In some embodiments, the second control unit 902 is further configured to gradually reduce the opening of the first target valve with a second value and reacquire the temperature difference between the maximum and minimum temperatures of the battery cell assembly after each adjustment until the temperature difference is obtained is not greater than a preset threshold and the adjustment is stopped.

[0096] In some embodiments, the first control unit 901 further uses voice to increase the opening of the first target valve by a first value and decrease the opening of the second target valve by a third value; the second target valve is a valve other than the first target valve among the first valve and the second valve; the second control unit 902 is further configured to decrease the opening of the first target valve by a second value and increase the opening of the second target valve by a fourth value at least once; the fourth value is less than the third value.

[0097] In some embodiments, the second control unit 902 is further configured to gradually decrease the opening of the first target valve with a second value and gradually increase the opening of the second target valve with a fourth value, and reacquire the temperature difference between the maximum and minimum temperatures of the battery cell assembly after each adjustment until the temperature difference is obtained is not greater than a preset threshold and the adjustment is stopped.

[0098] In some embodiments, the control device 900 may further include a third control unit and a fourth control unit.

[0099] The third control unit is used to control the operating speed of the circulating pump based on the temperature range where the maximum temperature is located at the first moment; the operating speed corresponds to the temperature range where the maximum temperature is located; wherein, the higher temperature range corresponds to the higher operating speed.

[0100] The fourth control unit is used to control the heat exchanger's heat exchange capacity based on the temperature range where the maximum temperature is located at the first moment; the heat exchange capacity corresponds to the temperature range where the maximum temperature is located; wherein, the higher temperature range corresponds to the higher heat exchange capacity.

[0101] Figure 10 This is a schematic diagram of the structure of a control device provided in an embodiment of this application, such as... Figure 10 As shown, the control device 1000 includes one or more processors 1010 and one or more memories 1020.

[0102] The processor 1010 can support the control device 1000 in implementing the methods described in the preceding method embodiments.

[0103] The memory 1020 stores a program that can be executed by the processor 1010, causing the processor 1010 to perform the methods described in the preceding method embodiments. The memory 1020 may be independent of the processor 1010 or integrated into the processor 1010.

[0104] Optionally, the control device 1000 may also include a transceiver 1030. The processor 1010 can communicate with other devices or chips through the transceiver 1030. For example, the processor 1010 can send and receive data with other devices or chips through the transceiver 1030.

[0105] This application provides a computer storage medium that stores one or more programs that can be executed by one or more processors to implement the steps of the methods described in any of the above embodiments.

[0106] It should be noted that the descriptions of the storage medium and device embodiments above are similar to those of the method embodiments above, and have similar beneficial effects. For technical details not disclosed in the storage medium and device embodiments of this application, please refer to the descriptions of the method embodiments of this application for understanding.

[0107] The aforementioned processor can be at least one of the following: application-specific integrated circuit (ASIC), digital signal processor (DSP), digital signal processing device (DSPD), programmable logic device (PLD), field-programmable gate array (FPGA), central processing unit (CPU), control module, microcontroller module, and microprocessor. It is understood that other electronic devices can also implement the functions of the aforementioned processor, and this application does not specifically limit the specific implementation.

[0108] The aforementioned computer storage media / memory can be read-only memory, programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), ferromagnetic random access memory (FRAM), flash memory, magnetic surface memory, optical disc, or compact disc read-only memory (CD ROM), etc.

[0109] This application provides a computer program including computer-readable code. When the computer-readable code runs in an electronic device, the processor in the electronic device executes some or all of the steps in the above-described method.

[0110] This application provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program. When the computer program is read and executed by a computer, it implements some or all of the steps in the above-described method. This computer program product can be implemented specifically through hardware, software, or a combination thereof. In some embodiments, the computer program product is specifically embodied as a computer storage medium; in other embodiments, the computer program product is specifically embodied as a software product, such as a software development kit (SDK), etc.

[0111] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It should be understood that in the various embodiments of this application, the sequence numbers of the above steps / processes do not imply a sequential order of execution; the execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application. The sequence numbers of the above embodiments of this application are merely descriptive and do not represent the superiority or inferiority of the embodiments.

[0112] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0113] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0114] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units. They may be located in one place or distributed across multiple network units. Some or all of the units may be selected to achieve the purpose of this embodiment according to actual needs.

[0115] In addition, each functional unit in the various embodiments of this application can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0116] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media that can store program code, such as mobile storage devices, read-only memory (ROM), magnetic disks, or optical disks.

[0117] Alternatively, if the integrated units described above are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence or the part that contributes to related technologies, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause an in-vehicle terminal (which may be a personal computer, server, or network device, etc.) to execute all or part of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROM, magnetic disks, or optical disks.

[0118] The above are merely embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

[0119] The above embodiments are merely preferred embodiments provided to fully illustrate this application, and the scope of protection of this application is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on this application are all within the scope of protection of this application.

Claims

1. A cooling system, characterized in that, Applied to vehicles, including: A cooling assembly includes a cold plate, a first valve, and a second valve. The cold plate is welded from an upper plate, a middle plate, and a lower plate. A first corrugated flow channel extending along the length of the cold plate is provided between the upper plate and the middle plate, and a second corrugated flow channel extending along the length of the cold plate is provided between the lower plate and the middle plate. The inlet of the first corrugated flow channel is located at a first end of the upper plate and connects to the first valve, and the outlet is located at a second end of the upper plate opposite to the first end. The inlet of the second corrugated flow channel is located at a second end of the lower plate and connects to the second valve, and the outlet is located at a first end of the lower plate opposite to the second end. The battery cell assembly includes an upper row of battery cells and a lower row of battery cells stacked alternately on the upper and lower sides of a cold plate; the upper row of battery cells is located in a first arcuate groove on the upper plate, and the lower row of battery cells is located in a second arcuate groove on the lower plate; in the length direction, the first arcuate groove and the second arcuate groove are arranged alternately; wherein, a row of battery cells includes at least one row of multiple cylindrical battery cells arranged horizontally along the length direction; The controller is configured to, upon detecting that the maximum temperature of the battery cell assembly exceeds a first threshold at a first moment, increase the opening of a first target valve corresponding to the location of the maximum temperature at the first moment by a first value; wherein the first target valve is either the first valve or the second valve; upon detecting that the temperature of the battery cell assembly decreases at a second moment after the first moment, based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly at the second moment, decrease the opening of the first target valve by a second value at least once to control the temperature difference of the battery cell assembly to be no greater than a preset threshold; wherein the second value is less than the first value.

2. The system according to claim 1, characterized in that, The system also includes a heat exchanger and a circulating pump; The inlet of the circulating pump is connected to the heat exchanger, and the outlet of the circulating pump is connected to the inlet of the first corrugated flow channel and the second corrugated flow channel; the circulating pump is used to deliver coolant to the cold plate assembly. The inlet of the heat exchanger is connected to the outlets of the first corrugated flow channel and the second corrugated flow channel, and the outlet of the heat exchanger is connected to the circulating pump; the heat exchanger is used to exchange heat with the coolant output by the cooling assembly.

3. The system according to claim 2, characterized in that, The controller is also used to adjust the operating speed of the circulating pump and / or the heat exchange capacity of the heat exchanger based on the temperature of the battery cell assembly.

4. A control method, characterized in that, The method, applied to a cooling system in a vehicle, includes: If the maximum temperature of the battery cell assembly exceeds a first threshold at a first moment, the opening of the first target valve corresponding to the location of the maximum temperature at the first moment will be increased by a first value; wherein, the first target valve is either a first valve or a second valve; If a temperature drop in the battery cell assembly is detected at a second time after the first time, and based on the temperature difference between the maximum and minimum temperatures of the battery cell assembly at the second time, the opening of the first target valve is reduced by a second value at least once to control the temperature difference of the battery cell assembly to be no greater than a preset threshold; the second value is less than the first value.

5. The method according to claim 4, characterized in that, The step of reducing the opening of the first target valve by a second value at least once includes: The opening of the first target valve is gradually reduced using the second value, and the temperature difference between the maximum and minimum temperatures of the battery cell assembly is re-acquired after each adjustment until the temperature difference is no greater than the preset threshold, at which point the adjustment is stopped.

6. The method according to claim 4, characterized in that, The step of increasing the opening of the first target valve corresponding to the location of the maximum temperature at the first moment by a first value includes: increasing the opening of the first target valve by a first value and decreasing the opening of the second target valve by a third value; the second target valve is the valve other than the first target valve among the first valve and the second valve. The step of reducing the opening of the first target valve by a second value at least once includes: reducing the opening of the first target valve by a second value at least once and increasing the opening of the second target valve by a fourth value; wherein the fourth value is less than the third value.

7. The method according to claim 6, characterized in that, The step of at least once decreasing the opening of the first target valve by a second value and at least once increasing the opening of the second target valve by a fourth value includes: The opening of the first target valve is gradually reduced with the second value, and the opening of the second target valve is gradually increased with the fourth value. After each adjustment, the temperature difference between the maximum and minimum temperatures of the battery cell assembly is re-acquired until the temperature difference is no greater than the preset threshold, at which point the adjustment stops.

8. The method according to claim 6 or 7, characterized in that, The first value and / or the third value correspond to the temperature range in which the maximum temperature is located; wherein, the higher the temperature range, the larger the corresponding first value and / or the third value.

9. The method according to any one of claims 4-7, characterized in that, The method further includes: The operating speed of the circulating pump is controlled based on the temperature range in which the maximum temperature is located at the first moment; the operating speed corresponds to the temperature range in which the maximum temperature is located; wherein, a higher temperature range corresponds to a higher operating speed.

10. The method according to any one of claims 4-7, characterized in that, The method further includes: The heat exchanger's heat exchange capacity is controlled based on the temperature range where the maximum temperature is located at the first moment; the heat exchange capacity corresponds to the temperature range where the maximum temperature is located; wherein, a higher temperature range corresponds to a higher heat exchange capacity.

Images