Temperature difference adjusting device and method of CTP battery pack

Abstract

The invention discloses a temperature difference adjusting device and method for a CTP battery pack. The device comprises an integrated frame, a plurality of integrated liquid cooling cross beams, a plurality of shunting sealing fixing bolts, a plurality of branch through-flow screw pipes, a plurality of connecting water pipes and a plurality of series water pipes, wherein each integrated liquid cooling cross beam corresponds to one branch of the CTP battery pack liquid cooling system; the branch through-flow solenoid is used for separating an integrated liquid cooling cross beam for temperature difference adjustment from the liquid cooling system; the series water pipe is used for connecting the branch through-flow screw pipes on the two adjacent integrated liquid cooling cross beams in the independent loop, and the independent loop comprises one or more independent integrated liquid cooling cross beams; and the connecting water pipe is used for connecting the branch through-flow screw pipes on the integrated liquid cooling cross beams on the two sides in the independent loop with external heat management equipment. According to the device, the specified temperature difference between the battery cells can be accurately and quickly produced, the temperature difference adjustment accuracy of the battery pack is improved, and the time cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of CTP battery parameter adjustment, and in particular to a temperature difference adjustment device and method for a CTP battery pack. Background Art

[0002] With the development of Cell to Pack (CTP) technology, CTP battery packs have been widely used in various fields such as electric vehicles. CTP battery packs are usually equipped with a liquid cooling system, and in order to ensure that the thermal management performance of the CTP battery pack can meet actual needs, the CTP battery pack needs to reach a specified temperature for thermal management performance testing.

[0003] In the related art, whether it is a single battery pack test or a vehicle integration test, the way to control each battery cell in the battery pack to reach the specified temperature is to leave the battery pack at the ambient temperature required for the test for a long time so that the battery cell temperature reaches the ambient temperature. However, the method in the above-mentioned related art requires a long standing time, and there will be a temperature difference between each battery cell. In some improved methods, the standing time is reduced by turning on additional heating or cooling functions, but the temperature difference still exists, and it is still necessary to continue standing after cooling or heating to reduce the temperature difference. Although the longer the standing time, the smaller the temperature difference, in actual applications, there is a limit to the standing time and it cannot be too long. Therefore, it is currently necessary to accept a certain degree of temperature difference when conducting tests.

[0004] However, in actual applications, temperature difference has a great impact on battery performance, so it is necessary to study the actual thermal management performance of CTP battery packs under a certain temperature difference. However, in the related technology, it is impossible to create a specified temperature difference between the cells of the battery pack. The temperature difference between the cells is random, which makes it impossible to perform thermal management performance tests under a specified temperature difference.

[0005] Therefore, how to accurately create a specified temperature difference between battery cells has become a problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of this application is to solve one of the above-mentioned technical problems at least to a certain extent.

[0007] To this end, the first purpose of this application is to propose a temperature difference adjustment device for a CTP battery pack. The device can accurately and quickly create a specified temperature difference between battery cells, improve the accuracy of temperature difference adjustment of the battery pack, reduce time cost, and is conducive to studying the actual thermal management performance of the battery pack under a specified temperature difference.

[0008] The second objective of the present application is to propose a temperature difference adjustment method for a CTP battery pack.

[0009] A third object of the present application is to provide a non-transitory computer-readable storage medium.

[0010] To achieve the above-mentioned purpose, the first embodiment of the present application proposes a temperature difference regulating device for a CTP battery pack, the device comprising: an integrated frame, a plurality of integrated liquid cooling beams, a plurality of shunt sealing fixing bolts, a plurality of branch flow through spiral tubes, a plurality of connecting water pipes and a plurality of series water pipes; wherein,

[0011] Each of the integrated liquid cooling beams corresponds to a branch of the liquid cooling system of the CTP battery pack, and the shunt sealing fixing bolts are used to fix the integrated liquid cooling beam that is not temperature-adjusted on the integrated frame to circulate the cooling liquid of the CTP battery pack itself;

[0012] The branch flow solenoid is used to independently separate the integrated liquid cooling beam for temperature difference regulation from the liquid cooling system;

[0013] The series water pipe is used to connect the branch flow spiral tubes on two adjacent integrated liquid cooling beams in an independent loop, wherein the independent loop includes one or more independent integrated liquid cooling beams;

[0014] The connecting water pipe is used to connect the branch flow spiral tubes on the integrated liquid cooling beams on both sides of the independent loop to the external thermal management equipment.

[0015] In addition, the temperature difference adjustment device of the CTP battery pack of the embodiment of the present application also has the following additional technical features:

[0016] Optionally, in some embodiments, the branch flow spiral tube includes: a first step, a first step thread, a second sealing ring, a third sealing ring, a second step, a fourth sealing ring, a bolt head, a spiral tube water inlet and outlet pipes, a first connecting channel and a second connecting channel; wherein, the first step thread is located at the front end of the first step, and the first step thread is used to thread and fix the branch flow spiral tube on the corresponding integrated liquid cooling beam; the second sealing ring is stuck in the groove of the rear section of the first step, the third sealing ring is located at the connection between the first step and the second step, and the fourth sealing ring is located at the connection between the second step and the bolt head; the first connecting channel runs through the spiral tube water inlet and outlet pipes, the second connecting channel runs through the bolt head, the second step and the first step, and the first connecting channel and the second connecting channel are connected.

[0017] Optionally, in some embodiments, the liquid cooling system includes one or more independent circuits, each of which is thermally controlled by the external thermal management device; the first connecting channel also includes: a rubber plug, which is used to block the coolant flowing out after the branch flow coil is installed.

[0018] To achieve the above object, a second embodiment of the present invention provides a temperature difference adjustment method for a CTP battery pack, which is applied to the temperature difference adjustment device for the CTP battery pack of the first aspect. The method comprises:

[0019] Place the CTP battery pack in the ambient temperature required for the thermal management performance test and obtain the current target temperature difference to be adjusted;

[0020] When the target temperature difference is zero, the temperature difference regulating device is used to perform temperature balancing on the CTP battery pack to adjust the temperature difference between the cells in the CTP battery pack to within a preset range;

[0021] When the target temperature difference is greater than zero, a temperature difference is created in the CTP battery pack by the temperature difference adjustment device, so as to adjust the difference between the highest battery cell temperature and the lowest battery cell temperature in the CTP battery pack to the target temperature difference;

[0022] Among them, in the process of performing the temperature equalization treatment and creating the temperature difference in the CTP battery pack, an independent circuit is constructed for the target battery cell that performs thermal management control separately through relevant components in the temperature difference adjustment device to accelerate the temperature rise or temperature drop of the target battery cell, or the integrated liquid cooling beam corresponding to the target battery cell is shielded to slow down the temperature rise or temperature drop of the target battery cell.

[0023] To achieve the above objectives, the third aspect of the present invention proposes a non-temporary computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the temperature difference adjustment method of the CTP battery pack as described in any one of the second aspect embodiments above is implemented.

[0024] The technical solution provided by the embodiments of the present application brings at least the following beneficial effects:

[0025] According to the actual temperature difference adjustment requirements, the present application can separate the relevant integrated liquid cooling beams of the CTP battery pack from the battery pack liquid cooling system through components such as branch flow solenoids, connecting water pipes and series water pipes, thereby accelerating or slowing down the temperature rise or temperature drop of the relevant battery cells, and creating a specified temperature difference between the various battery cells in the battery pack. Therefore, on the one hand, the present application can accelerate the temperature balance between the various battery cells and reduce the static time of the battery pack by accelerating or decelerating. On the other hand, it can also accelerate the creation of a fixed temperature difference between the various battery cells by accelerating or decelerating, thereby reducing the time required to create a specified temperature difference and reducing the time cost of battery pack testing. In addition, the present application can accurately create a specified temperature difference between the battery cells, reducing the deviation between the actual temperature difference between the battery cells and the specified temperature difference, so that test items related to the temperature difference can be added during the battery pack test, and the comprehensiveness of the battery pack test and the robustness of the thermal management performance can be improved. In addition, since the present application can create an accurate specified temperature difference, the accuracy of the battery pack test results can be improved, and the reliability of the test results can be ensured. Therefore, the present application improves the accuracy of battery pack temperature difference regulation, reduces time cost, and is conducive to studying the actual thermal management performance of the battery pack under a specified temperature difference.

[0026] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0028] Figure 1 A schematic diagram of the structure of a temperature difference adjustment device for a CTP battery pack proposed in an embodiment of the present application;

[0029] Figure 2 A schematic diagram of the structure of another temperature difference regulating device for a CTP battery pack proposed in an embodiment of the present application;

[0030] Figure 3 A cross-sectional schematic diagram of a flow splitter seal fixing bolt proposed in an embodiment of the present application;

[0031] Figure 4 A schematic diagram of the structure of a branch flow solenoid proposed in an embodiment of the present application;

[0032] Figure 5 A cross-sectional schematic diagram of a branch flow-through solenoid proposed in an embodiment of the present application;

[0033] Figure 6 A schematic diagram of a flow channel of an independent circuit proposed in an embodiment of the present application;

[0034] Figure 7 A schematic diagram of a flow channel of a shielded liquid cooling system proposed in an embodiment of the present application;

[0035] Figure 8 A schematic diagram of a liquid cooling system under an acceleration scheme proposed in an embodiment of the present application;

[0036] Fig. 9 Schematic diagram of a liquid cooling system under a deceleration scheme proposed in an embodiment of the present application

[0037] Fig.10 A flow chart of a temperature difference adjustment monitoring method for a CTP battery pack proposed in an embodiment of the present application;

[0038] Fig.11 A flow chart of a temperature equalization acceleration processing method based on an acceleration method proposed in an embodiment of the present application;

[0039] Fig.12 A flow chart of a temperature equalization acceleration processing method based on a deceleration method proposed in an embodiment of the present application;

[0040] Fig.13 A flow chart of a manufacturing method for a target temperature difference based on an acceleration method proposed in an embodiment of the present application;

[0041] Fig.14 This is a flow chart of a method for manufacturing a target temperature difference based on a deceleration method proposed in an embodiment of the present application. DETAILED DESCRIPTION

[0042] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0043] The temperature difference adjustment device and method of the CTP battery pack according to the embodiment of the present application will be described below with reference to the accompanying drawings.

[0044] Figure 1 This is a schematic diagram of the structure of a temperature difference adjustment device for a CTP battery pack proposed in an embodiment of the present application. Figure 2 This is a schematic diagram of the structure of another temperature difference adjustment device for a CTP battery pack proposed in an embodiment of the present application, such as Figure 1 and Figure 2 As shown, the device includes: an integrated frame 10, a plurality of integrated liquid cooling beams 20, a plurality of shunt sealing fixing bolts 30, a plurality of branch flow through spiral tubes 40, a plurality of connecting water pipes 50 and a plurality of series water pipes 60.

[0045] Among them, each integrated liquid-cooling beam 20 corresponds to a branch of the CTP battery liquid cooling system. On one side of the CTP battery pack, each integrated liquid-cooling beam 20 is equipped with a shunt sealing fixing bolt 30 or a branch flow screw 40 (determined according to whether the temperature difference of the branch is adjusted separately). The shunt sealing fixing bolt 30 and the branch flow screw 40 both have their own sealing structure, and the corresponding integrated liquid-cooling beam 20 and the integrated frame 10 are fixed together by screwing.

[0046] The shunt sealing fixing bolt 30 is used to fix the integrated liquid cooling beam 20 without temperature difference adjustment on the integrated frame 10 to circulate the cooling liquid of the CTP battery pack. The cooling liquid circulates in the channel formed by the integrated frame 10, the integrated liquid cooling beam 20 and the shunt sealing fixing bolt 30. The cooling liquid circulation of the CTP battery pack is the thermal management cycle of the battery pack itself, including its own liquid cooling cycle and liquid heat cycle.

[0047] For example, when the CTP battery pack circulates the coolant, the coolant first flows into the integrated frame 10 from the water inlet, then flows into the integrated liquid cooling beam 20 through the first shunt channel and the second shunt channel in the shunt sealing fixing bolt 30, and then flows into the integrated frame 10 on the other side through the first shunt channel and the second shunt channel in the shunt sealing fixing bolt 30 on the other side, and finally flows out from the water outlet.

[0048] The branch flow solenoid 40 is used to separate the integrated liquid cooling beam for temperature difference regulation from the liquid cooling system. The series water pipe 60 is used to connect the branch flow solenoid 40 on two adjacent integrated liquid cooling beams in an independent loop, wherein the independent loop includes one or more independent integrated liquid cooling beams 20. The connecting water pipe 50 is used to connect the branch flow solenoid 40 on the integrated liquid cooling beams on both sides of the independent loop to an external thermal management device.

[0049] Specifically, Figure 1 As shown, when separate thermal management control is required for several branches, the shunt sealing fixing bolts 30 on each integrated liquid-cooled beam 20 are removed, and the branch flow solenoids 40 are installed respectively. The installed branch flow solenoids 40 can separate the integrated liquid-cooled beam from the CTP battery pack liquid cooling system to set up an independent loop or shield the branch.

[0050] When setting up an independent loop, the series water pipe 60 is used to connect the two branch flow solenoids 40 to achieve the series connection of the corresponding two integrated liquid cooling beams. The two connecting water pipes 50 are respectively connected to the branch flow solenoids 40 at the water inlet and outlet in the independent loop, and the external thermal management device, which can be an external refrigerator or other thermal management control device that can heat or cool the independent loop separately. When constructing an independent loop, the connecting water pipe 50 and the series water pipe 60 can be fixed to the branch flow solenoids 40 by clamps.

[0051] The components in the temperature difference regulating device of the present application are described in detail below.

[0052] A possible implementation method is to divide the flow sealing fixing bolt 30 into a bolt head, a first step, a second step, a second sealing ring, a third sealing ring and a fourth sealing ring. Figure 3 As shown, the front end of the first step has a thread for connection and fixing. The second step is provided with a second diversion channel 12, and the first step and the second step are provided with a first diversion channel 11, and the first diversion channel 11 and the second diversion channel 12 are connected to each other.

[0053] The second sealing ring is stuck in the position without thread in the rear section of the first step, and a groove can be opened here to clamp the second sealing ring. The third sealing ring is located at the connection between the first step and the second step, and is generally pasted on the vertical end face on the left side of the second step diagram. The fourth sealing ring is located at the connection between the second step and the bolt head, and is generally pasted on the vertical end face on the left side of the bolt head diagram. The coolant can flow from the flow channel in the integrated frame into the second shunt channel, and then flow out to the integrated liquid cooling beam after passing through the first shunt channel, and vice versa.

[0054] In one embodiment of the present application, Figure 4 As shown, the branch flow spiral tube includes: a first step 41, a first step thread 42, a second sealing ring 43, a third sealing ring 44, a second step 45, a fourth sealing ring 46, a bolt head 47, and a spiral tube water inlet and outlet pipe 48.

[0055] Among them, the first step thread 42 is located at the front end of the first step 41, and the first step thread 41 is used to screw the branch flow solenoid to the corresponding integrated liquid cooling beam. The second sealing ring 43 is stuck in the groove of the rear section of the first step 41, the third sealing ring 44 is located at the connection between the first step 41 and the second step 42, and the fourth sealing ring 46 is located at the connection between the second step 45 and the bolt head 47. The setting method and function of each sealing ring in the branch flow solenoid 40 are consistent with the sealing ring in the shunt sealing fixing screw 30, which can achieve the sealing between the two connected components.

[0056] like Figure 5As shown, the interior of the branch flow spiral tube 40 also includes a first connecting channel 1 and a second connecting channel 2, wherein the first connecting channel 1 passes through the spiral tube water inlet and outlet pipes 48, and the second connecting channel 2 passes through the bolt head 47, the second step 45 and the first step 41, and the first connecting channel 1 and the second connecting channel 2 are connected.

[0057] The principle of using the temperature difference adjustment device of the present application to perform individual thermal management control on the relevant integrated liquid-cooled beam is described in detail below.

[0058] In one embodiment of the present application, one or more independent loops can be constructed in the liquid cooling system of the CTP battery pack, and each independent loop is thermally managed and controlled by an external thermal management device. Among them, each independent loop may include one or more integrated liquid cooling beams, and several integrated liquid cooling beams can be connected in series as a separate cooling loop according to actual adjustment needs. For example, at least one integrated liquid cooling beam is used as an independent loop, and at most all integrated liquid cooling beams are connected in series as an independent loop. Several integrated liquid cooling beams can also be connected in series to form multiple independent series loops, and the number of integrated liquid cooling beams included in each independent loop can be the same or different.

[0059] For example, Figure 6 As shown, three integrated liquid cooling beams can be connected in series to form an independent circuit, which includes two series water pipes and two connecting water pipes on both sides. Figure 6 After being connected in series in the manner shown, the three integrated liquid cooling beams in series will be independent of the battery pack liquid cooling system and will be independently thermally managed by an external refrigerator. Through independent thermal management control, such as heating or cooling, the temperature rise or drop of the battery cell corresponding to the independent circuit can be accelerated, thereby achieving temperature difference adjustment through the "acceleration" method of this application.

[0060] In one embodiment of the present application, Figure 7 As shown, when the branch flow solenoid is installed only on one side of the integrated liquid cooling beam, the integrated liquid cooling beam after the branch flow solenoid is installed will no longer have the coolant in the CTP battery pack liquid cooling system circulating in and out, thereby achieving the independence of the integrated liquid cooling beam from the CTP battery pack liquid cooling system, shielding the influence of the battery pack liquid cooling system on the integrated liquid cooling beam.

[0061] During specific implementation, when performing the branch shielding operation, the branch flow spiral tube is generally installed on the integrated frame on the water inlet side, and can also be installed on the integrated frame on the water outlet side. In this embodiment, the first connecting channel also includes: a rubber plug, which is used to block the coolant flowing out after the branch flow spiral tube is installed. That is, if coolant still flows out of the corresponding integrated liquid cooling beam after the branch flow spiral tube is installed, a rubber plug can be plugged into the first connecting channel of the branch flow spiral tube to achieve a greater shielding effect and completely block the coolant circulation in the battery pack liquid cooling system.

[0062] Based on this facility mode, since the integrated liquid cooling beam no longer has the coolant circulation in the CTP battery pack liquid cooling system after the branch flow spiral is installed, the branch is not affected by the thermal management cycle of the battery pack itself. Therefore, the temperature rise or drop of the corresponding battery cell can be further slowed down, thereby realizing temperature difference regulation through the "deceleration" method of this application.

[0063] The following is a detailed description of the process of applying the above acceleration and deceleration schemes in a CTP battery pack liquid cooling system in actual applications.

[0064] As an example, Figure 8 As shown, when applying the above acceleration scheme for temperature difference adjustment, in order to save resources, a series water pipe can be used on two adjacent integrated liquid cooling beams in the CTP battery pack liquid cooling system to form a series loop, and the number of integrated liquid cooling beams in series is determined according to actual needs. Connecting water pipes are set on the integrated liquid cooling beams on the outside of both sides of the independent loop, which are connected to the external refrigerator through the connecting water pipes, and the circuit is independently thermally managed and controlled by the external refrigerator. The remaining branches in the liquid cooling system can execute the thermal management cycle of the CTP battery pack itself.

[0065] As another example, Fig. 9 As shown, when the above deceleration scheme is applied for temperature difference adjustment, a branch flow solenoid is installed on one side of the branch that needs additional separate temperature difference adjustment, and the number of integrated liquid cooling beams to be shielded is determined according to actual needs. The remaining branches in the liquid cooling system can perform the thermal management cycle of the CTP battery pack itself.

[0066] In summary, the temperature difference regulating device of the CTP battery pack of the embodiment of the present application can make the relevant integrated liquid cooling beam of the CTP battery pack independent of the battery pack liquid cooling system through components such as branch flow spiral tubes, connecting water pipes and series water pipes according to the actual temperature difference regulation requirements, thereby accelerating or slowing down the temperature rise or temperature drop of the relevant battery cells, and creating a specified temperature difference between the various battery cells in the battery pack. Therefore, on the one hand, the device can accelerate the temperature balance between the various battery cells and reduce the standing time of the battery pack by accelerating or decelerating, and on the other hand, it can also accelerate the creation of a fixed temperature difference between the various battery cells by accelerating or decelerating, thereby reducing the time required to create a specified temperature difference and reducing the time cost of battery pack testing. Therefore, the device improves the accuracy of the temperature difference regulation of the battery pack, reduces the time cost, and is conducive to studying the actual thermal management performance of the battery pack under a specified temperature difference.

[0067] In order to more clearly illustrate the specific implementation process of temperature difference regulation of the CTP battery pack by the temperature difference regulation device of the CTP battery pack, a temperature difference regulation method of the CTP battery pack proposed in the embodiment of the present application is described in detail below. The method is applied to the temperature difference regulation device of the CTP battery pack in the above embodiment, that is, the temperature difference regulation device in the above embodiment is used to perform separate thermal management control on the branches corresponding to the relevant cells in the CTP battery pack to implement the temperature difference regulation method of this embodiment. The monitoring device involved in the method includes various components as described in the above embodiment, which will not be repeated here.

[0068] Fig.10 This is a flow chart of a temperature difference adjustment monitoring method for a CTP battery pack proposed in an embodiment of the present application, such as Fig.10 As shown, the method comprises the following steps:

[0069] Step S101: placing the CTP battery pack in an environment temperature required for a thermal management performance test, and obtaining a target temperature difference to be adjusted.

[0070] Among them, the ambient temperature is the specified temperature required for the thermal management performance test of the CTP battery pack, and the target temperature difference is the specified temperature difference currently to be manufactured. The present application manufactures the specified target temperature difference in the CTP battery pack, thereby facilitating the subsequent thermal management performance test of the CTP battery pack under the condition of the target temperature difference.

[0071] Specifically, the CTP battery pack is placed in an ambient temperature and allowed to stand, and a target temperature difference determined according to the thermal management performance test requirements is obtained. The target temperature difference may be zero or a fixed value greater than zero.

[0072] Step S102: When the target temperature difference is zero, the temperature difference regulating device is used to perform temperature balancing on the CTP battery pack to adjust the temperature difference between the cells in the CTP battery pack to within a preset range.

[0073] Specifically, when the target temperature difference to be manufactured is zero, the temperatures of the cells in the CTP battery pack need to be adjusted to be consistent so that the temperature difference between the cells approaches zero. Therefore, the present application performs temperature balancing on the CTP battery pack through a temperature difference adjustment device.

[0074] Among them, in the process of temperature equalization of the battery pack, the acceleration scheme described in the above embodiment can be used for adjustment, that is, through the relevant components in the temperature difference adjustment device, an independent circuit is constructed for the target battery cell that is individually thermally managed to accelerate the temperature rise or temperature drop of the target battery cell. Alternatively, the deceleration scheme in the above embodiment can also be used for adjustment, that is, the integrated liquid cooling beam corresponding to the target battery cell is shielded to slow down the temperature rise or temperature drop of the target battery cell.

[0075] It should be noted that the acceleration scheme of the present application is applicable to scenarios where there are available thermal management devices externally, such as refrigerators. When there are external thermal management devices, this adjustment method can be used regardless of whether it is a battery pack test or a vehicle test. The deceleration scheme of the present application can be applicable to scenarios where there are no available thermal management devices externally, such as when testing under the vehicle's winter test standards and summer test standards. Of course, the deceleration scheme of the present application can also be used in scenarios where there are available refrigerators externally.

[0076] The following describes in detail the process of temperature equalization of the CTP battery pack using the acceleration scheme and the deceleration scheme adopted in this application.

[0077] In one embodiment of the present application, in a scenario where an acceleration solution is adopted, a temperature equalization process is performed on a CTP battery pack by a temperature difference adjustment device, including the following steps:

[0078] First, the temperature of each battery cell in the CTP battery pack is detected, and the temperature of each battery cell is compared with a preset target temperature, where the target temperature is determined based on the test requirements and the ambient temperature.

[0079] Specifically, after the CTP battery pack is placed in the ambient temperature required for the test and allowed to stand, the temperature of each battery cell in the battery pack is detected by a temperature detection device, and then each battery cell temperature is compared with the target temperature to determine the relationship between each battery cell temperature and the target temperature.

[0080] Among them, the target temperature is related to the requirements of thermal management performance testing, and there is a corresponding relationship between the target temperature and the ambient temperature. For example, when the ambient temperature is extremely low, the target temperature is also extremely low.

[0081] Then, according to the relationship between the temperature of each battery cell and the target temperature, the corresponding battery pack thermal management cycle (including the battery pack's own liquid heating cycle and liquid cooling cycle) is performed, and based on the target temperature difference to be adjusted, the target temperature and the temperature of each battery cell after the battery pack thermal management cycle, the target battery cell that needs to be separated from the CTP battery pack liquid cooling system is determined.

[0082] Then, the components of the corresponding temperature difference adjustment device are installed on the integrated liquid cooling beam corresponding to the target battery cell to form an independent loop, and a separate thermal management cycle is performed on the independent loop or the battery pack thermal management cycle is repeated until the battery cell temperature difference of the CTP battery pack meets the target temperature difference.

[0083] Among them, since the relationship between the temperature of each battery cell and the target temperature may exist in various situations, in order to more clearly explain the specific implementation process of temperature balancing in various situations, the following is combined with Fig.11 The specific method shown is described in detail.

[0084] As the first case, when all battery cell temperatures are greater than the target temperature, the battery pack is liquid-cooled in a cycle until the lowest battery cell temperature reaches the target temperature, and the battery cell whose difference between the current battery cell temperature and the lowest battery cell temperature is greater than a preset temperature threshold is used as the target battery cell.

[0085] Specifically, if Fig.11 As shown, the liquid cooling cycle of the battery pack's own liquid cooling system is started until the lowest cell temperature among all the cells in the battery pack drops to the target temperature. Then the liquid cooling cycle is stopped, and the real-time temperature of each cell is detected, and the difference between the real-time temperature of each cell and the lowest cell temperature is calculated, and the cells with a difference greater than 1°C are selected as target cells. There may be one or more target cells, and the temperature difference between the target cell and the target temperature does not meet the temperature balance requirement.

[0086] Furthermore, a plurality of integrated liquid-cooling beams corresponding to each target battery cell are formed into an independent loop through a temperature difference regulating device, and a liquid cooling cycle is performed on the independent loop through an external thermal management device until the lowest battery cell temperature in the area corresponding to the independent loop reaches the target temperature.

[0087] Specifically, the position of the integrated liquid cooling beam corresponding to the target battery cell is determined, wherein one integrated liquid cooling beam may correspond to multiple battery cells. Then the corresponding integrated liquid cooling beam and the two beams connected to the beam are arranged according to Figure 6 The scheme shown constructs an independent loop, and starts an external refrigerator connected to the independent loop to perform an additional liquid cooling cycle on the independent loop until the lowest cell temperature in each cell in the area corresponding to the independent loop is equal to the target temperature.

[0088] In this way, the temperature of each battery cell in the area corresponding to the independent circuit can be basically adjusted to within 1°C from the target temperature, thereby achieving the goal of adjusting the temperature of each battery cell in the battery pack to within 1°C from the target temperature, thus meeting the temperature balance requirements of the battery pack in practical applications.

[0089] As the second case, when all cell temperatures are lower than the target temperature, the battery pack liquid is thermally cycled until the highest cell temperature reaches the target temperature, and the cell whose difference between the current cell temperature and the highest cell temperature is greater than the temperature threshold is taken as the target cell.

[0090] Specifically, continue Fig.11 In the example shown, the liquid heat cycle of the battery pack's own liquid cooling system is started until the highest cell temperature among all the cells in the battery pack reaches the target temperature. Then the liquid heat cycle is stopped, and the real-time temperature of each cell is detected, and the difference between the real-time temperature of each cell and the highest cell temperature is calculated, and the cells with a difference greater than 1°C are selected as target cells.

[0091] Furthermore, a plurality of integrated liquid-cooling beams corresponding to each target battery cell are combined into an independent loop through a temperature difference regulating device, and a liquid-heat circulation is performed on the independent loop through an external thermal management device until the highest battery cell temperature in the area corresponding to the independent loop reaches the target temperature.

[0092] Specifically, determine the position of the integrated liquid cooling beam corresponding to each target battery cell, also according to Figure 6 The scheme shown constructs an independent loop, and starts an external refrigerator connected to the independent loop to perform additional liquid heat circulation on the independent loop until the highest cell temperature in each cell in the area corresponding to the independent loop is equal to the target temperature.

[0093] Thus, the temperature of each battery cell in the area corresponding to the independent circuit can be basically adjusted to within 1°C from the target temperature, thereby achieving the goal of adjusting the temperature of each battery cell in the battery pack to within 1°C from the target temperature.

[0094] As the third case, when the target temperature is a non-threshold temperature, the highest cell temperature among all the cell temperatures is compared with the preset differentiation temperature, and the corresponding battery pack thermal management cycle is performed according to the comparison result, and the target cell and the thermal management control method of the target cell are determined according to the battery pack thermal management cycle result.

[0095] Specifically, in addition to the first and second cases mentioned above, that is, when some battery cells have temperatures greater than the target temperature and some battery cells have temperatures less than the target temperature, the highest battery cell temperature among all battery cell temperatures is compared with the separation temperature. Fig.11In the example shown, 20° C. is used as the differentiation temperature, and the differentiation temperature can be determined based on the thermal management performance of the thermal management cycle system of the battery pack itself.

[0096] When the maximum cell temperature is greater than the distinguishing temperature, the battery pack's own liquid cooling cycle is started, and when the maximum cell temperature drops to the target temperature, the second case is returned to determine the target cell and perform separate thermal management control on the target cell. When the maximum cell temperature is less than or equal to the distinguishing temperature, the battery pack's own liquid thermal cycle is started, and when the maximum cell temperature rises to the target temperature, the first case is returned to determine the target cell and perform separate thermal management control on the target cell.

[0097] Therefore, this embodiment can adjust the difference between the temperature of each battery cell in the battery pack and the target temperature to within 1°C under various conditions. For individual battery cells that are not adjusted to within 1°C or whose temperature changes over time, they can be readjusted by circulating within the battery pack itself or leaving it to stand.

[0098] In one embodiment of the present application, in a scenario where a deceleration scheme is adopted, a temperature equalization process is performed on a CTP battery pack by a temperature difference adjustment device, including the following steps:

[0099] First, this embodiment also detects the temperature of each battery cell in the CTP battery pack and compares the temperature of each battery cell with the preset target temperature. Since there may be many situations in which the size relationship between the temperature of each battery cell and the target temperature exists, in order to more clearly explain the specific implementation process of temperature balancing processing by the deceleration scheme in various situations, the following is combined with Fig.12 The specific method shown is described in detail.

[0100] As the first case, when the temperature of all cells is greater than the target temperature, the battery pack liquid cooling cycle is performed until the lowest cell temperature among the temperatures of all cells in the battery pack drops to the target temperature, and the cell whose difference between the current cell temperature and the lowest cell temperature is less than or equal to the temperature threshold (i.e., 1°C) is used as the target cell. In this embodiment, the temperature difference between the target cell and the target temperature meets the requirement of temperature balance.

[0101] Furthermore, a branch flow solenoid is installed on one side of the multiple integrated liquid-cooling beams corresponding to the target battery cells, and the battery pack liquid cooling cycle and target battery cell selection are cyclically performed until the number of cycles is reached or the temperature difference of all battery cells is less than or equal to the temperature threshold.

[0102] Specifically, determine the position of the integrated liquid cooling beam corresponding to the target battery cell, and then place the corresponding integrated liquid cooling beam and the two beams connected to the beam in front and behind according to Figure 7The solution shown is to set up branch flow solenoids to shield the three integrated liquid cooling beams. Then, the battery pack itself is liquid cooled for the cells other than the target cells. During the cycle, it is continuously monitored whether there are new target cells that meet the requirements in this round, and branch flow solenoids are installed for the new target cells in this round until the temperature difference of all cells is less than or equal to 1°C or the limit of the number of cycles is reached.

[0103] As the second case, continue Fig.12 In the example shown, when all the cell temperatures are lower than the target temperature, the battery pack itself is subjected to liquid thermal circulation until the highest cell temperature among all the cell temperatures in the battery pack reaches the target temperature, and the cell whose difference between the current cell temperature and the highest cell temperature is less than or equal to the temperature threshold is taken as the target cell.

[0104] Furthermore, a branch flow solenoid is installed on one side of the multiple integrated liquid cooling beams corresponding to the target battery cells, and the battery pack liquid heat cycle and target battery cell selection are cyclically performed until the number of cycles is reached or the temperature difference of all battery cells is less than or equal to the temperature threshold. The process of installing the branch flow solenoid for the target battery cell and repeating the cycle can refer to the implementation method of the first case above, which will not be repeated here.

[0105] As the third case, when the target temperature is a non-threshold temperature, the highest cell temperature among all the cell temperatures is compared with the preset differentiation temperature, and the corresponding battery pack thermal management cycle is performed according to the comparison result, and the target cell and the thermal management control method of the target cell are determined according to the battery pack thermal management cycle result.

[0106] Among them, in the temperature equalization processing process based on the deceleration method of this embodiment, the processing method in the third case is the same as the processing process in the above-mentioned temperature equalization processing embodiment based on the acceleration method. The specific implementation method can be found in Fig.12 The relevant descriptions in the above embodiments will not be repeated here.

[0107] Therefore, this embodiment can adjust the difference between the temperature of each battery cell in the battery pack and the target temperature to within 1°C under various conditions. For battery cells whose temperature difference with the target temperature is still greater than 1°C after exceeding the limit of the battery pack's own thermal management cycle times, they can be adjusted through the battery pack's own internal circulation until the temperature difference of all battery cells with the target temperature is within 1°C.

[0108] It should be noted that in the above-mentioned embodiments of temperature equalization processing based on the acceleration method and the deceleration method, parameters such as the preset temperature value, the number of cycles and the number of components of the temperature difference adjustment device set can be adjusted according to actual needs, and this application does not impose any restrictions on this.

[0109] In one embodiment of the present application, the heat preservation of the battery cells that have reached the target temperature in subsequent operations is also considered during the above-mentioned temperature equalization process. If the temperature difference between the target temperature and the ambient temperature is too large, the target temperature can be appropriately increased or decreased to facilitate temperature compensation for subsequent operations, thereby avoiding the need for repeated temperature equalization operations, reducing the number of operations, and improving regulation efficiency.

[0110] For example, when the ambient temperature is lower than the target temperature, the target temperature is increased, and when the ambient temperature is higher than the target temperature, the target temperature is decreased.

[0111] Based on the above embodiments, it should also be noted that since the temperature equalization process requires the use of the battery pack's own thermal management circulation system or external thermal management equipment, and in actual applications the refrigeration equipment may not be able to meet the minimum refrigeration requirements required for the target temperature, this application also proposes a processing method to accelerate temperature equalization in extreme cases.

[0112] Among them, since the cooling and heating capabilities of the external refrigeration equipment or the vehicle thermal management system (i.e., the battery pack thermal management circulation system when the vehicle is tested) are limited, when the target temperature is an extreme temperature, the temperature equalization method in the above embodiment needs to be adjusted. However, since the current heating capabilities of the external thermal management equipment and the vehicle thermal management system can cover the high temperature conditions of the battery, only the extremely low temperature conditions need to be considered under this condition. That is, when the target temperature is extremely low and the refrigeration equipment cannot meet the refrigeration needs, it is necessary to adopt the temperature equalization method for extreme conditions proposed in this embodiment. It can be seen from the above description that based on the correlation between the target temperature and the ambient temperature, the ambient temperature is usually also extremely low at this time.

[0113] In this embodiment, when the target temperature is extremely low temperature, the temperature equalization treatment of the CTP battery pack is performed by a temperature difference adjustment device, including the following steps: first, whether the cooling capacity of the external thermal management device and the battery pack thermal management system is suitable for the target temperature; if it is not suitable for the target temperature, the maximum cell temperature is adjusted to the target temperature by leaving the CTP battery pack at ambient temperature; then, the cell whose difference between the current cell temperature and the maximum cell temperature is greater than the temperature threshold is taken as the target cell, and an independent circuit is constructed for each target cell for heating until the difference between the temperature of each target cell and the target temperature is less than the temperature threshold, or, the cell whose difference between the current cell temperature and the maximum cell temperature is less than or equal to the temperature threshold is taken as the target cell, a branch flow coil is installed on one side of multiple integrated liquid cooling beams corresponding to each target cell, and the battery pack liquid heat cycle is circulated until the difference between the temperature of all cells and the target temperature is less than the temperature threshold.

[0114] Specifically, in this embodiment, there are also two types of temperature balancing processing methods under extreme temperatures: a temperature balancing processing method under extreme temperatures based on an acceleration method, and a temperature balancing processing method under extreme temperatures based on a deceleration method.

[0115] For the temperature equalization treatment method under extreme temperature based on the acceleration method, the battery pack or vehicle is first placed in a low temperature environment. When the highest cell temperature reaches the target temperature, the integrated liquid cooling beam and the two front and rear beams where the cells with a temperature lower than the target temperature -1°C are located are individually connected in series as a loop for heating. When the temperature of a cell involved in the cycle equals the target temperature during the cycle, the cycle of the branch is stopped. This is done until the temperature of all cells involved in the cycle is ≥ the target temperature -1°C and ≤ the target temperature +1°C.

[0116] For example, assuming the ambient temperature is -15°C, the minimum water temperature of the refrigeration equipment is 5°C, and the target battery cell temperature is -10°C, the refrigeration equipment does not meet the demand. In this embodiment, the battery pack is first placed in an ambient temperature of -15°C until the maximum battery cell temperature = -10°C. The integrated liquid cooling beam and the two front and rear beams where the battery cells with a temperature of <-11°C are located are heated by a separate series circuit. When the temperature of a battery cell participating in the circulation is -10°C during the circulation process, the circulation of the branch is stopped until the temperature of all battery cells participating in the circulation is within -10±1°C.

[0117] For the temperature equalization treatment method under extreme temperature based on the deceleration method, the battery pack or vehicle is also placed in a low temperature environment first. When the highest battery cell temperature reaches the target temperature, for all battery cells except those with a temperature lower than the target temperature -1°C, the integrated liquid cooling beam and the two front and rear beams are equipped with branch flow solenoids. Start the battery pack's own liquid thermal cycle. When the temperature of a battery cell participating in the cycle is equal to the target temperature during the cycle, the corresponding integrated liquid cooling beam and the two front and rear beams are equipped with branch flow solenoids until the temperature of all battery cells participating in the cycle is ≥ the target temperature -1°C and ≤ the target temperature +1°C.

[0118] For example, assuming the ambient temperature is -15°C, the minimum water temperature of the vehicle thermal management is 5°C, and the target battery cell temperature is -10°C, the thermal management of the vehicle does not meet the requirements. In this embodiment, the vehicle is first placed in an ambient temperature of -15°C until the maximum battery cell temperature = -10°C. For the battery cells other than the battery cells with a temperature <-11°C, the integrated liquid cooling beam and the two front and rear beams are equipped with branch flow solenoids. Start the liquid-heat cycle of the vehicle thermal management system. During the cycle, when the temperature of the battery cells involved in the cycle = -10°C, the corresponding integrated liquid cooling beam and the two front and rear beams are equipped with branch flow solenoids until the temperature of all battery cells involved in the cycle is within -10±1°C.

[0119] In this embodiment, it is also necessary to consider the heat preservation of the battery cell that has reached the target temperature in subsequent operations. If the temperature difference with the ambient temperature is too large, the target temperature can be appropriately increased or decreased for temperature compensation in subsequent operations to avoid the need to repeat the temperature equalization operation. For example, if the ambient temperature is lower than the target temperature, the target temperature is increased, and if the ambient temperature is higher than the target temperature, the target temperature is decreased.

[0120] Step S103: when the target temperature difference is greater than zero, a temperature difference is created in the CTP battery pack by a temperature difference adjustment device, so as to adjust the difference between the highest cell temperature and the lowest cell temperature in the CTP battery pack to be the target temperature difference.

[0121] Specifically, when the target temperature difference to be manufactured is a fixed value greater than zero, the difference between the highest cell temperature and the lowest cell temperature among the temperatures of the cells in the CTP battery pack needs to be adjusted to the target temperature difference, so as to ensure that the temperature difference between the cells in the battery pack is within the range of the target temperature difference. To this end, the present application manufactures the target temperature difference in the CTP battery pack through a temperature difference adjustment device.

[0122] In the process of creating the target temperature difference in the battery pack, the acceleration scheme described in the above embodiment can also be used for adjustment, that is, through the relevant components in the temperature difference adjustment device, an independent circuit is constructed for the target battery cell that is individually thermally managed to accelerate the temperature rise or temperature drop of the target battery cell. Alternatively, the deceleration scheme in the above embodiment can also be used for adjustment, that is, the integrated liquid cooling beam corresponding to the target battery cell is shielded to slow down the temperature rise or temperature drop of the target battery cell.

[0123] It should be noted that, similar to the temperature equalization process in the previous step, in the process of manufacturing the target temperature difference, the acceleration scheme of the present application is also applicable to the scenario where there is an available thermal management device externally, such as a refrigerator. When there is an external thermal management device, this adjustment method can be used regardless of whether it is a battery pack test or a vehicle test. The deceleration scheme of the present application can be applied to scenarios where there is no available thermal management device externally, such as when testing under the vehicle's winter test standards and summer test standards. Of course, the deceleration scheme of the present application can also be used in scenarios where there is an available refrigerator externally.

[0124] The following describes in detail the process of creating a target temperature difference in a CTP battery pack using an acceleration scheme and a deceleration scheme in the present application.

[0125] In one embodiment of the present application, in a scenario where an acceleration scheme is adopted, a process of manufacturing a target temperature difference in a CTP battery pack by a temperature difference regulating device includes the following steps:

[0126] First, the temperature of each battery cell in the CTP battery pack is detected, and the temperature of each battery cell is compared with the preset minimum target temperature, where the target temperature difference is equal to the maximum target temperature minus the minimum target temperature.

[0127] Specifically, after the CTP battery pack is placed in the ambient temperature required for the test and allowed to stand, the temperature of each battery cell in the battery pack is detected by a temperature detection device, and then each battery cell temperature is compared with the minimum target temperature to determine the relationship between each battery cell temperature and the minimum target temperature.

[0128] Among them, the target temperature difference to be adjusted is equal to the highest target temperature minus the lowest target temperature. The lowest target temperature is similar to the setting method of the target temperature in the previous step, and is also related to the requirements of the thermal management performance test. There is a corresponding relationship between the lowest target temperature and the ambient temperature. For example, when the ambient temperature is extremely low, the lowest target temperature is also extremely low.

[0129] Then, according to the relationship between the temperature of each battery cell and the minimum target temperature, the corresponding battery pack thermal management cycle (including the battery pack's own liquid heating cycle and liquid cooling cycle) is performed, and based on the target temperature difference to be adjusted, the maximum target temperature, the minimum target temperature and the temperature of each battery cell after the battery pack thermal management cycle, the target battery cell that needs to be separated from the CTP battery pack liquid cooling system is determined.

[0130] Then, the components of the corresponding temperature difference adjustment device are installed on the integrated liquid cooling beam corresponding to the target battery cell to form an independent loop, and a separate thermal management cycle is performed on the independent loop until the difference between the highest battery cell temperature and the lowest battery cell temperature of the CTP battery pack is the target temperature difference.

[0131] Among them, since the relationship between the temperature of each battery cell and the minimum target temperature may exist in various situations, in order to more clearly explain the specific implementation process of creating the target temperature difference in various situations, the following is combined with Fig.13 The specific method shown is described in detail.

[0132] As the first case, when all the battery cell temperatures are greater than the minimum target temperature, the battery pack liquid cooling cycle is performed until the highest battery cell temperature among all the battery cells is the minimum target temperature plus the target temperature difference, and the lowest battery cell temperature is the minimum target temperature.

[0133] Specifically, if Fig.13 As shown, the liquid cooling cycle of the battery pack's own liquid cooling system is started until the highest cell temperature among all the cell temperatures in the battery pack first drops to the lowest target temperature plus the target temperature difference, and a branch flow solenoid is installed on the integrated liquid cooling beam corresponding to the cell with the highest cell temperature, and then the lowest cell temperature drops to the target temperature.

[0134] Then, stop the liquid cooling cycle, take the battery cell that needs to be heated up as the target battery cell, and use the temperature difference adjustment device to form an independent loop with multiple integrated liquid cooling beams corresponding to each target battery cell. Use external thermal management equipment to perform liquid heat circulation on the independent loop until the highest battery cell temperature in the corresponding area of ​​the independent loop is greater than or equal to the lowest target temperature plus the target temperature.

[0135] Specifically, the battery cell that needs to be heated can be a battery cell specified according to the test requirements, or a battery cell with a higher temperature after the above liquid cooling cycle is completed. After the above liquid cooling cycle until the lowest battery cell temperature drops to the target temperature, the highest battery cell temperature that first reaches the lowest target temperature plus the target temperature difference may change. Therefore, this embodiment selects the battery cell that needs to be heated as the target battery cell, and the target battery cell can be one or more.

[0136] Then, an independent loop is set for each target battery cell, and an additional liquid thermal cycle is performed on the target battery cell separately through an external thermal management device connected to the independent loop until the highest battery cell temperature in the corresponding area of ​​the independent loop is greater than or equal to the lowest target temperature plus the target temperature.

[0137] As a result, the difference between the highest cell temperature and the lowest cell temperature among the temperatures of all the cells in the battery pack is made greater than or equal to the target temperature difference, thereby creating a specified target temperature difference in the battery pack.

[0138] As the second case, continue to refer to Fig.13 In the example shown, when there is a cell temperature that is stably less than or equal to the target temperature, the battery pack liquid is thermally cycled until the highest cell temperature of all cells is the lowest target temperature plus the target temperature difference, and the lowest cell temperature is the lowest target temperature.

[0139] Furthermore, the battery cells that need to be heated are taken as target battery cells, and the multiple integrated liquid-cooling beams corresponding to each target battery cell are formed into an independent loop through a temperature difference adjustment device, and the independent loop is subjected to liquid heat circulation through an external thermal management device until the highest battery cell temperature in the area corresponding to the independent loop is greater than or equal to the lowest target temperature plus the target temperature.

[0140] It should be noted that the implementation method of the liquid heat circulation for the independent loop in the second case of this embodiment is the same as that in the first case, and will not be repeated here.

[0141] Therefore, this embodiment can adjust the difference between the highest cell temperature and the lowest cell temperature in the battery pack to the target temperature difference under various conditions, thereby achieving a specified target temperature difference in the battery pack.

[0142] In one embodiment of the present application, in a scenario where a deceleration scheme is adopted, a process of creating a target temperature difference in a CTP battery pack by a temperature difference adjustment device includes the following steps:

[0143] First, this embodiment also detects the temperature of each battery cell in the CTP battery pack and compares the temperature of each battery cell with the preset minimum target temperature. Since there may be many situations in which the magnitude relationship between the temperature of each battery cell and the minimum target temperature exists, in order to more clearly explain the specific implementation process of creating a target temperature difference in the battery pack with the deceleration scheme in various situations, the following is combined with Fig.14 The specific method shown is described in detail.

[0144] As the first case, when all the battery cell temperatures are greater than the minimum target temperature, the battery pack liquid cooling cycle is performed until the highest battery cell temperature among all the battery cells is the minimum target temperature plus the target temperature difference, or the lowest battery cell temperature is the minimum target temperature.

[0145] Furthermore, the liquid cooling cycle is stopped, and the cell corresponding to the highest cell temperature or the lowest cell temperature that meets the judgment condition in the previous step is taken as the target cell, and a branch flow solenoid is installed on one side of the multiple integrated liquid cooling beams corresponding to the target cell, and the battery pack liquid cooling cycle is cyclically performed. During each cycle, it is detected in real time whether a new target cell that meets the judgment condition in the previous step has appeared, and a branch flow solenoid is installed for the new target cell that meets the judgment condition, until the highest cell temperature among all cells is the lowest target temperature plus the target temperature difference, and the lowest cell temperature is the lowest target temperature.

[0146] As the second case, continue to refer to Fig.14 In the example shown, when all the cell temperatures are lower than the minimum target temperature, the battery pack liquid is thermally cycled until the highest cell temperature of all the cells is the minimum target temperature plus the target temperature difference, or the lowest cell temperature is the minimum target temperature;

[0147] Furthermore, the liquid thermal cycle is stopped, and the cell corresponding to the highest cell temperature or the lowest cell temperature that meets the judgment conditions in the previous step is taken as the target cell, and a branch flow solenoid is installed on one side of the multiple integrated liquid cooling beams corresponding to the target cell, and the battery pack liquid thermal cycle and target cell selection are cyclically performed. During each round of battery pack liquid thermal cycle, it is also detected in real time whether a new target cell that meets the judgment conditions in the previous step has appeared, and a branch flow solenoid is installed for the new target cell that meets the judgment conditions, until the highest cell temperature among all the cells is the lowest target temperature plus the target temperature difference, and the lowest cell temperature is the lowest target temperature.

[0148] As the third case, when the lowest target temperature is a non-threshold temperature, a battery pack liquid cooling cycle is performed until the highest cell temperature among all the battery cells is the lowest target temperature plus the target temperature difference, and the lowest cell temperature among all the current cell temperatures is compared with the lowest target temperature, and the corresponding battery pack thermal management cycle is performed according to the comparison result.

[0149] For details, please refer to Fig.14 In the example shown, in addition to the first and second cases mentioned above, that is, when the temperature of some battery cells is greater than the minimum target temperature and the temperature of some battery cells is less than the minimum target temperature, the battery pack itself is liquid-cooled in a cycle until the highest battery cell temperature among all the battery cells is the minimum target temperature plus the target temperature difference.

[0150] Then, stop the liquid cooling cycle, take the cell corresponding to the highest cell temperature as the target cell, and record the position of the integrated liquid cooling beam corresponding to the target cell. Then compare the lowest cell temperature among all current cell temperatures with the lowest target temperature. If the lowest cell temperature is lower than the lowest target temperature, return to the second case mentioned above, first install the branch flow solenoid on the integrated liquid cooling beam corresponding to the currently determined target cell, and cycle the liquid heat cycle of the battery pack itself and the selection of the target cell. If the lowest cell temperature is higher than the lowest target temperature, return to the first case mentioned above, first install the branch flow solenoid on the integrated liquid cooling beam corresponding to the currently determined target cell, and cycle the liquid cooling cycle of the battery pack itself and the selection of the target cell.

[0151] Therefore, this embodiment can adjust the difference between the highest cell temperature and the lowest cell temperature in the battery pack to the target temperature difference under various conditions, thereby achieving a specified target temperature difference in the battery pack.

[0152] It should be noted that in the above-mentioned embodiments of manufacturing the target temperature difference based on the acceleration method and the deceleration method, parameters such as the preset temperature value, the number of cycles, and the number of components of the temperature difference regulating device to be set can also be adjusted according to actual needs, and this application does not impose any restrictions on this. In this embodiment, the corresponding integrated liquid-cooled crossbeam is installed with a branch flow-through solenoid and an independent circuit is set. The setting method in the above-mentioned embodiment can be referred to, and the implementation process is the same. Moreover, in this embodiment, in the process of manufacturing the temperature difference, the insulation of the battery cell that has reached the target temperature in subsequent operations is considered, and the method of increasing or decreasing the target temperature can refer to the description in the relevant embodiments of the above-mentioned temperature equalization process. The implementation process is the same and will not be repeated here.

[0153] Based on the above embodiments, it is also necessary to explain that since the battery pack's own thermal management circulation system or external thermal management equipment is also needed in the above-mentioned manufacturing target temperature difference processing process, and in actual applications the refrigeration equipment may not be able to meet the minimum refrigeration requirements required for the target temperature, this application also proposes a manufacturing target temperature difference processing method under extreme circumstances.

[0154] Among them, the target temperature difference manufacturing method under extreme conditions of this embodiment also only considers the extremely low temperature condition. That is, when the lowest target temperature is extremely low temperature and the refrigeration equipment cannot meet the refrigeration requirements, the target temperature difference manufacturing method under extreme conditions proposed in this embodiment needs to be adopted. From the above description, it can be seen that based on the correlation between the lowest target temperature and the ambient temperature, the ambient temperature is usually also extremely low temperature at this time.

[0155] In this embodiment, when the minimum target temperature is an extremely low temperature, a temperature difference is created in the CTP battery pack by a temperature difference adjustment device, including the following: first, detecting whether the cooling capacity of the external thermal management device and the battery pack thermal management system is suitable for the minimum target temperature; if it is not suitable for the minimum target temperature, adjusting the maximum battery cell temperature to the maximum target temperature by leaving the CTP battery pack at ambient temperature; then, taking the battery cell whose current battery cell temperature is lower than the minimum target temperature as the target battery cell, constructing an independent circuit for each target battery cell for heating until the temperature of each target battery cell is within the interval formed by the maximum target temperature and the minimum target temperature, or taking the battery cell whose current battery cell temperature is greater than or equal to the minimum target temperature as the target battery cell, installing a branch flow coil on one side of multiple integrated liquid cooling beams corresponding to each target battery cell, and cyclically performing the battery pack liquid heat cycle until the temperature of all batteries is within the interval.

[0156] Specifically, in this embodiment, there are also two types of manufacturing methods for achieving a target temperature difference at an extreme temperature based on an acceleration method and a manufacturing method for achieving a target temperature difference at an extreme temperature based on a deceleration method.

[0157] For the manufacturing method of the target temperature difference under extreme temperature based on the acceleration method, the battery pack or vehicle is first placed in a low temperature environment. When the highest cell temperature reaches the highest target temperature, the integrated liquid cooling beam and the two front and rear beams where the cells with a temperature lower than the lowest target temperature are located are separately connected in series with a loop for heating. When the temperature of a cell involved in the cycle equals the lowest target temperature during the cycle, the cycle of the branch is stopped. This is done until the temperature of all cells involved in the cycle is ≥ the lowest target temperature and ≤ the highest target temperature.

[0158] For example, assuming the ambient temperature is -15°C, the minimum water temperature of the refrigeration equipment is 5°C, the minimum target cell temperature is -10°C, and the maximum target cell temperature is 0°C, the refrigeration equipment does not meet the demand. In this embodiment, the battery pack is first placed in an ambient temperature of -15°C until the maximum cell temperature = 0°C. The integrated liquid cooling beam and the two front and rear beams where the cells with a temperature <-10°C are located are individually connected in series with a loop for heating. When the temperature of a cell participating in the cycle = -10°C during the cycle, the circulation of the branch is stopped until the temperature of all cells participating in the cycle is within the range of -5±5°C.

[0159] For the manufacturing method of the target temperature difference under extreme temperature based on the deceleration method, the battery pack or vehicle is first placed in a low temperature environment. When the highest cell temperature reaches the highest target temperature, the integrated liquid cooling beam and the two front and rear beams are installed with branch flow solenoids for the cells except for the cells whose temperature is lower than the lowest target temperature. The battery pack's own liquid thermal cycle is started. When the temperature of the cell involved in the cycle is equal to the lowest target temperature during the cycle, the corresponding integrated liquid cooling beam and the two front and rear beams are installed with branch flow solenoids until the temperature of all cells involved in the cycle is ≥ the lowest target temperature and ≤ the highest target temperature.

[0160] For example, assuming the ambient temperature is -15°C, the minimum water temperature of the vehicle thermal management is 5°C, the minimum target battery cell temperature is -10°C, and the maximum target battery cell temperature is 0°C, the thermal management of the vehicle does not meet the requirements. In this embodiment, the vehicle is first placed in an ambient temperature of -15°C until the maximum battery cell temperature = 0°C, and the integrated liquid cooling beam and the front and rear beams where the battery cells other than the battery cells with a temperature <-10°C are located are equipped with branch flow solenoids. Start the battery pack's own liquid thermal cycle. During the cycle, when the temperature of the battery cells involved in the cycle = -10°C, the corresponding integrated liquid cooling beam and the front and rear beams are equipped with branch flow solenoids until the temperature of all battery cells involved in the cycle = -5±5°C.

[0161] In this embodiment, it is also necessary to consider the heat preservation of the battery cell that has reached the target temperature in subsequent operations. If the temperature difference with the ambient temperature is too large, the target temperature can be appropriately increased or decreased for temperature compensation in subsequent operations to avoid the need to repeat the temperature equalization operation. For example, if the ambient temperature is lower than the target temperature, the target temperature is increased, and if the ambient temperature is higher than the target temperature, the target temperature is decreased.

[0162] In summary, the temperature difference adjustment method of the CTP battery pack of the embodiment of the present application can, on the one hand, accelerate the temperature balance between each battery cell and reduce the static time of the battery pack by accelerating or decelerating. On the other hand, it can also accelerate or decelerate to speed up the creation of a fixed temperature difference between each battery cell, thereby reducing the time required to create a specified temperature difference and reducing the time cost of the battery pack test. In addition, the method can accurately create a specified temperature difference between the battery cells, reducing the deviation between the actual temperature difference between the battery cells and the specified temperature difference, so that test items related to the temperature difference can be added during the battery pack test, and the comprehensiveness of the battery pack test and the robustness of the thermal management performance can be improved. In addition, since the method can create an accurate specified temperature difference, the accuracy of the battery pack test results can be improved, and the reliability of the test results can be ensured. Therefore, the method improves the accuracy of the battery pack temperature difference adjustment, reduces the time cost, and is conducive to studying the actual thermal management performance of the battery pack under the specified temperature difference.

[0163] In order to implement the above-mentioned embodiment, the present application also proposes a non-temporary computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the temperature difference adjustment method of the CTP battery pack proposed in the second aspect embodiment of the present application is implemented.

[0164] It should be noted that it should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0165] In addition, in the description of the present application, the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0166] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0167] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0168] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0169] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A temperature difference regulating device for a CTP battery pack, characterized in that: include: An integrated frame, multiple integrated liquid cooling beams, multiple split flow sealing fixing bolts, multiple branch flow spiral tubes, multiple connecting water pipes and multiple series water pipes; wherein, Each of the integrated liquid cooling beams corresponds to a branch of the liquid cooling system of the CTP battery pack, and the shunt sealing fixing bolts are used to fix the integrated liquid cooling beam that is not temperature-adjusted on the integrated frame to circulate the cooling liquid of the CTP battery pack itself; The branch flow solenoid is used to independently separate the integrated liquid cooling beam for temperature difference regulation from the liquid cooling system; The series water pipe is used to connect the branch flow spiral tubes on two adjacent integrated liquid cooling beams in an independent loop, wherein the independent loop includes one or more independent integrated liquid cooling beams; The connecting water pipe is used to connect the branch flow spiral tubes on the integrated liquid cooling beams on both sides of the independent loop to the external thermal management equipment.

2. The temperature difference regulating device of the CTP battery pack according to claim 1, characterized in that: The branch flow spiral tube comprises: a first step, a first step thread, a second sealing ring, a third sealing ring, a second step, a fourth sealing ring, a bolt head, a spiral tube water inlet and outlet pipes, a first connecting channel and a second connecting channel; wherein, The first step thread is located at the front end of the first step, and the first step thread is used to thread and fix the branch flow spiral tube on the corresponding integrated liquid cooling beam; The second sealing ring is clamped in the groove of the rear section of the first step, the third sealing ring is located at the connection between the first step and the second step, and the fourth sealing ring is located at the connection between the second step and the bolt head; The first connecting channel passes through the spiral water inlet and outlet pipes, and the second connecting channel passes through the bolt head, the second step and the first step, and the first connecting channel and the second connecting channel are connected.

3. The temperature difference regulating device of the CTP battery pack according to claim 2, characterized in that: The liquid cooling system comprises one or more independent circuits, each of which is thermally managed and controlled by the external thermal management device; The first connecting channel also includes a rubber plug, which is used to block the coolant flowing out after the branch flow spiral tube is installed.

4. A temperature difference adjustment method for a CTP battery pack, characterized in that: The temperature difference adjustment device for a CTP battery pack according to any one of claims 1 to 3, wherein the temperature difference adjustment method comprises the following steps: Place the CTP battery pack in the ambient temperature required for the thermal management performance test and obtain the current target temperature difference to be adjusted; When the target temperature difference is zero, the temperature difference regulating device is used to perform temperature balancing on the CTP battery pack to adjust the temperature difference between the cells in the CTP battery pack to within a preset range; When the target temperature difference is greater than zero, a temperature difference is created in the CTP battery pack by the temperature difference adjustment device, so as to adjust the difference between the highest battery cell temperature and the lowest battery cell temperature in the CTP battery pack to the target temperature difference; Among them, in the process of performing the temperature equalization treatment and creating the temperature difference in the CTP battery pack, an independent circuit is constructed for the target battery cell that performs thermal management control separately through relevant components in the temperature difference adjustment device to accelerate the temperature rise or temperature drop of the target battery cell, or the integrated liquid cooling beam corresponding to the target battery cell is shielded to slow down the temperature rise or temperature drop of the target battery cell.

5. The temperature difference adjustment method of the CTP battery pack according to claim 4, characterized in that: The temperature equalization process of the CTP battery pack is performed by the temperature difference adjustment device, including: Detecting the temperature of each battery cell in the CTP battery pack, and comparing the temperature of each battery cell with a preset target temperature, wherein the target temperature is determined based on the test requirements and the ambient temperature; When all the battery cell temperatures are greater than the target temperature, a battery pack liquid cooling cycle is performed until the lowest battery cell temperature reaches the target temperature, and a battery cell whose difference between the current battery cell temperature and the lowest battery cell temperature is greater than a preset temperature threshold is used as a target battery cell; The multiple integrated liquid-cooling beams corresponding to each of the target battery cells are combined into the independent loop through the temperature difference adjustment device, and the independent loop is liquid-cooled by an external thermal management device until the lowest battery cell temperature in the area corresponding to the independent loop reaches the target temperature; When all the battery cell temperatures are lower than the target temperature, thermal cycle the battery pack liquid until the highest battery cell temperature reaches the target temperature, and use the battery cell whose difference between the current battery cell temperature and the highest battery cell temperature is greater than the temperature threshold as the target battery cell; The multiple integrated liquid cooling beams corresponding to each of the target battery cells are combined into the independent loop through the temperature difference adjustment device, and the independent loop is subjected to liquid heat circulation through an external thermal management device until the highest battery cell temperature in the area corresponding to the independent loop reaches the target temperature; When the target temperature is a non-threshold temperature, the highest battery cell temperature among all battery cell temperatures is compared with the preset differentiation temperature, and the corresponding battery pack thermal management cycle is performed according to the comparison result, and the target battery cell and the thermal management control method of the target battery cell are determined according to the battery pack thermal management cycle result.

6. The temperature difference adjustment method of the CTP battery pack according to claim 5, characterized in that: The temperature equalization process of the CTP battery pack by the temperature difference adjustment device also includes: When all the battery cell temperatures are greater than the target temperature, a battery pack liquid cooling cycle is performed until the lowest battery cell temperature reaches the target temperature, and a battery cell whose difference between the current battery cell temperature and the lowest battery cell temperature is less than or equal to the temperature threshold is used as a target battery cell; Installing a branch flow solenoid on one side of the multiple integrated liquid cooling beams corresponding to the target battery cells, and cyclically performing battery pack liquid cooling and target battery cell selection until the number of cycles is reached or the temperature difference of all battery cells is less than or equal to the temperature threshold; When all the battery cell temperatures are lower than the target temperature, thermal cycle the battery pack liquid until the highest battery cell temperature reaches the target temperature, and use the battery cell whose difference between the current battery cell temperature and the highest battery cell temperature is lower than or equal to the temperature threshold as the target battery cell; A branch flow solenoid is installed on one side of the multiple integrated liquid cooling beams corresponding to the target battery cells, and the battery pack liquid thermal cycle and target battery cell selection are cyclically performed until the number of cycles is reached or the temperature difference of all battery cells is less than or equal to the temperature threshold.

7. The temperature difference adjustment method of the CTP battery pack according to claim 5, characterized in that: When the target temperature is an extremely low temperature, the temperature equalization process of the CTP battery pack is performed by the temperature difference adjustment device, and further includes: Detecting whether the cooling capacity of the external thermal management device and the battery pack thermal management system is suitable for the target temperature; In the case where the target temperature is not applicable, adjusting the maximum cell temperature to the target temperature by leaving the CTP battery pack at rest in the ambient temperature; The battery cell whose difference between the current battery cell temperature and the highest battery cell temperature is greater than the temperature threshold is taken as the target battery cell, and an independent circuit is constructed for each target battery cell to heat the battery cell until the difference between the temperature of each target battery cell and the target temperature is less than the temperature threshold; or, The battery cell whose difference between the current battery cell temperature and the maximum battery cell temperature is less than or equal to the temperature threshold is taken as the target battery cell, a branch flow coil is installed on one side of the multiple integrated liquid-cooled beams corresponding to each target battery cell, and the battery pack liquid thermal cycle is circulated until the difference between the temperature of all battery cells and the target temperature is less than the temperature threshold.

8. The temperature difference adjustment method of the CTP battery pack according to claim 4, characterized in that: The step of creating a temperature difference in the CTP battery pack by using the temperature difference regulating device comprises: Detecting the temperature of each battery cell in the CTP battery pack, and comparing the temperature of each battery cell with a preset minimum target temperature, wherein the target temperature difference is equal to the maximum target temperature minus the minimum target temperature; When all the battery cell temperatures are greater than the minimum target temperature, a battery pack liquid cooling cycle is performed until the highest battery cell temperature among all the battery cells is the minimum target temperature plus the target temperature difference, and the lowest battery cell temperature is the minimum target temperature; In the case where there is a battery cell that is stably less than or equal to the minimum target temperature, thermally cycle the battery pack liquid until the highest battery cell temperature of all battery cells is the minimum target temperature plus the target temperature difference, and the lowest battery cell temperature is the minimum target temperature; The battery cell that needs to be heated is taken as the target battery cell, and the multiple integrated liquid-cooling beams corresponding to each of the target battery cells are formed into the independent loop through the temperature difference adjustment device, and the independent loop is subjected to liquid heat circulation through an external thermal management device until the highest battery cell temperature in the area corresponding to the independent loop is greater than or equal to the lowest target temperature plus the target temperature.

9. The temperature difference adjustment method of the CTP battery pack according to claim 8, characterized in that: The step of creating a temperature difference in the CTP battery pack by the temperature difference regulating device further includes: When the temperatures of all the battery cells are greater than the minimum target temperature, a battery pack liquid cooling cycle is performed until the highest battery cell temperature of all the battery cells is the minimum target temperature plus the target temperature difference, or the lowest battery cell temperature is the minimum target temperature; The battery cell corresponding to the highest battery cell temperature or the lowest battery cell temperature is taken as the target battery cell, a branch flow solenoid is installed on one side of the multiple integrated liquid cooling beams corresponding to the target battery cell, and the battery pack liquid cooling cycle and the target battery cell selection are cyclically performed until the highest battery cell temperature among all the battery cells is the lowest target temperature plus the target temperature difference, and the lowest battery cell temperature is the lowest target temperature; When all the battery cell temperatures are lower than the minimum target temperature, thermally cycle the battery pack liquid until the highest battery cell temperature among all the battery cells is the minimum target temperature plus the target temperature difference, or the lowest battery cell temperature is the minimum target temperature; The cell corresponding to the highest cell temperature or the lowest cell temperature is taken as the target cell, a branch flow solenoid is installed on one side of the multiple integrated liquid cooling beams corresponding to the target cell, and the battery pack liquid thermal cycle and the target cell selection are cyclically performed until the highest cell temperature of all the cells is the lowest target temperature plus the target temperature difference, and the lowest cell temperature is the lowest target temperature; When the minimum target temperature is a non-threshold temperature, a battery pack liquid cooling cycle is performed until the highest battery cell temperature among all battery cells is the minimum target temperature plus the target temperature difference, and the lowest battery cell temperature among all current battery cell temperatures is compared with the minimum target temperature, and a corresponding battery pack thermal management cycle is performed based on the comparison result.

10. The temperature difference adjustment method of the CTP battery pack according to claim 8, characterized in that: The step of creating a temperature difference in the CTP battery pack by the temperature difference regulating device further includes: Detecting whether the cooling capacity of the external thermal management device and the battery pack thermal management system is suitable for the minimum target temperature; In the case where the minimum target temperature is not applicable, adjusting the maximum cell temperature to the maximum target temperature by leaving the CTP battery pack at rest in the ambient temperature; The battery cells whose current battery cells are lower than the minimum target temperature are taken as target battery cells, and an independent circuit is constructed for each of the target battery cells to perform heating until the temperature of each of the target battery cells is within the range formed by the maximum target temperature and the minimum target temperature; or, The battery cell whose current battery cell temperature is greater than or equal to the minimum target temperature is taken as the target battery cell, a branch flow coil is installed on one side of the multiple integrated liquid cooling beams corresponding to each of the target battery cells, and the battery pack liquid heat cycle is circulated until the temperature of all the battery cells is within the said range.

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