Thermal management control method and system for CTP battery pack

Abstract

The invention provides a thermal management control method and system for a CTP battery pack, and the method comprises the following steps: constructing a temperature control structure model of the CTP battery pack, the temperature control structure model comprises a plurality of liquid cooling plates, each liquid cooling plate is internally provided with a flow blocking strip, and the flow blocking strips are used for changing the trend of a heat exchange medium; a flow channel in each liquid cooling plate forms reciprocating broken line type water jacket circulation, and the initial length of a flow blocking strip and the initial aperture of a water inlet and a water outlet of each liquid cooling plate are preset; acquiring parameter data of the CTP battery pack for triggering temperature control starting in a continuous overcharge state, simulating the temperature control structure model according to the parameter data, and acquiring a thermal simulation cloud picture of each liquid cooling plate area; according to the method, through a built temperature control structure model of the CTP battery pack, the length of a flow blocking strip and the aperture of an inlet and an outlet are adjusted according to simulation, the flowing path and flow of cooling liquid in a liquid cooling plate are optimized, temperature distribution of the battery pack is improved, the phenomenon of local overheating or supercooling is avoided, and the service life of the battery pack is prolonged. And a thermal management control strategy is formulated for the temperature control structure to ensure that the battery cell works in an optimal temperature interval, so that the thermal management performance of the battery pack is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of thermal management control of a CTP battery pack, and in particular to a thermal management control method and system for a CTP battery pack. Background Art

[0002] New energy power batteries are widely used in various electric vehicles due to their high efficiency and environmental protection. However, battery performance is easily affected by temperature changes. Too high or too low temperature may damage battery life. The application of thermal management devices and methods can effectively regulate battery temperature and ensure that it operates in a suitable working environment, thereby improving the efficiency and safety of the battery. In addition, thermal management devices can also reduce safety risks caused by battery overheating and prevent accidents caused by thermal runaway of batteries. Therefore, thermal management devices are an indispensable and important part of battery packs and play a key role in improving the overall performance and safety of electric vehicles.

[0003] A liquid cooling plate assembly, a battery assembly and a vehicle with publication number CN219226418U, the liquid cooling plate assembly comprising: a harmonica tube, comprising a plurality of cooling channels extending along the length direction of the harmonica tube, the two side walls of the harmonica tube in the thickness direction forming a first heat dissipation portion, the harmonica tube being arranged between two battery cells for dissipating the heat of the two battery cell side walls; and a cooling plate, being arranged on at least one side in the width direction of the harmonica tube, forming a second heat dissipation portion for dissipating the heat of a battery connecting piece connecting the two battery cells; the liquid cooling plate assembly utilizes the first heat dissipation portion to cool the large surfaces of the two side walls of the battery cell, and can also utilize the second heat dissipation portion to absorb the heat generated when current passes through the battery connecting piece, thereby cooling the battery connecting piece.

[0004] The existing liquid cooling plate assembly currently uses a large area of ​​liquid cooling plate between the sides of the battery cell as a heat exchange device to cooperate with the heat conductive layer between the battery cell and the liquid cooling plate to quickly exchange heat. When designing the structural model, it is impossible to optimize the flow channel structure to improve the temperature distribution of the battery pack, resulting in local overheating or overcooling, and it is impossible to generate a targeted temperature control strategy for battery pack thermal management, and thus it is impossible to ensure that the battery cell works in the most suitable temperature range, thereby reducing the thermal management performance of the battery pack. Summary of the invention

[0005] In view of this, the present invention proposes a thermal management control method and system for a CTP battery pack. By constructing a temperature control structure model of the CTP battery pack and adjusting the length of the baffle bar and the inlet and outlet apertures according to simulation, the flow path and flow rate of the coolant in the liquid cooling plate can be optimized, the temperature distribution of the battery pack can be improved, and local overheating or overcooling can be avoided. A thermal management control strategy is formulated for the temperature control structure to ensure that the battery cells work in the most suitable temperature range, thereby improving the thermal management performance of the battery pack.

[0006] The technical solution of the present invention is implemented as follows: The present invention provides a thermal management control method for a CTP battery pack, the method comprising the following steps:

[0007] S1, constructing a temperature control structure model of a CTP battery pack, the temperature control structure model includes a plurality of liquid cooling plates, each of which is provided with a flow-blocking bar, the flow-blocking bar is used to change the direction of the heat exchange medium, so that the flow channel in each liquid cooling plate forms a reciprocating zigzag water jacket circulation, and the initial length of the flow-blocking bar and the initial aperture of the water inlet and outlet of each liquid cooling plate are preset;

[0008] S2, obtaining parameter data of the CTP battery pack triggering the temperature control to start in the continuous overcharging state, simulating the temperature control structure model according to the parameter data, and obtaining the thermal simulation cloud map of each liquid cooling plate area;

[0009] S3, according to the thermal simulation cloud map of each liquid cooling plate, respectively adjust the length of the corresponding flow blocking bar to make the temperature distribution on each liquid cooling plate uniform, and determine the final flow blocking bar length of each liquid cooling plate;

[0010] S4, based on the adjusted temperature control structure model, simulating the temperature control structure model, adjusting the apertures of the water inlet and the water outlet of each liquid cooling plate, finding the optimal aperture combination to keep the temperature balanced, and obtaining the corresponding flow curve;

[0011] S5, forming a final temperature control structure model of the CTP battery pack according to the final baffle bar length and optimal aperture combination of each liquid cooling plate;

[0012] S6, based on the final temperature control structure model, sets the battery pack temperature control strategy under different working conditions to control the thermal management of the battery pack.

[0013] On the basis of the above technical solution, preferably, the temperature control structure further includes a total water inlet pipeline and a total water outlet pipeline, wherein:

[0014] Several liquid cooling plates are arranged in sequence along the width direction, and the battery cells are abutted between two adjacent liquid cooling plates. A water inlet and a water outlet are provided on each liquid cooling plate.

[0015] The water inlet of each liquid cooling plate is connected to the main water inlet pipeline for providing heat exchange medium to the liquid cooling plate, and the water outlet of each liquid cooling plate is connected to the main water outlet pipeline for circulation of heat exchange medium in the liquid cooling plate;

[0016] The water inlet end of the main water inlet pipeline and the water outlet end of the main water outlet pipeline are arranged on the same side.

[0017] On the basis of the above technical scheme, preferably, the temperature control structure also includes a plurality of composite material strips and a thermal conductive adhesive layer, wherein symmetrically arranged composite material strips are provided on both sides of each liquid cooling plate, a thermal conductive adhesive layer is provided between two corresponding composite material strips on the same side, the battery cell is abutted against the composite material strip through the thermal conductive adhesive layer, and the thermal conductive adhesive layer serves as a heat exchange and heat conductive medium for the battery cell.

[0018] On the basis of the above technical solution, preferably, the liquid cooling plate further includes a first harmonica tube, a second harmonica tube, a first current collector, a second current collector and a crushing bar, wherein:

[0019] The first harmonica pipe and the second harmonica pipe are respectively arranged on both sides of the crushing stop bar, and a plurality of parallel flow channels are arranged in the first harmonica pipe and the second harmonica pipe;

[0020] There are two flow-blocking bars, and the two flow-blocking bars are respectively arranged on both sides of the second harmonica tube and are centrally symmetrically arranged, so that the heat exchange medium forms a reciprocating zigzag flow in the parallel flow channels in the second harmonica tube;

[0021] The first current collector and the second current collector are respectively arranged on both sides of the first harmonica tube and the second harmonica tube, the water inlet and the water outlet are both opened on the first current collector, the water inlet is connected with the liquid inlet end of the first harmonica tube, the liquid outlet end of the first harmonica tube is connected with one end of the second current collector, the other end of the second current collector is connected with the liquid inlet end of the second harmonica tube, and the liquid outlet end of the second harmonica tube is connected with the water outlet, so as to make the flow channel in each liquid cooling plate form a reciprocating zigzag water jacket circulation.

[0022] On the basis of the above technical solution, preferably, the step S2 of obtaining parameter data for triggering temperature control to be turned on in a continuous overcharging state of a CTP battery pack, simulating the temperature control structure model according to the parameter data, and obtaining a thermal simulation cloud map of each liquid cooling plate area includes the following sub-steps:

[0023] Get the heat generation power of the CTP battery pack under continuous overcharge state, the expression is:

[0024] P=I 2 *R

[0025] In the formula, P is heating power, I is peak current, and R is the internal resistance of the battery cell;

[0026] Preset the supercharge cooling temperature threshold and the suitable working temperature of the battery pack, use the supercharge cooling temperature threshold as the inlet temperature of the temperature control structure, and use the suitable working temperature of the battery pack as the outlet temperature of the temperature control structure;

[0027] According to the preset supercharge cooling temperature threshold and the suitable operating temperature of the battery pack, the temperature difference between the inlet and outlet of the temperature control structure is calculated;

[0028] Select the heat exchange medium, and calculate the inlet flow rate of the temperature control structure according to the heat generation power, parameters of the heat exchange medium and temperature difference under the overcharge state. The expression is:

[0029] V q =P / (C*ρ*△T)

[0030] Where V q is the inlet flow rate of the temperature control structure, P is the heat generation power under supercharging state, C is the specific heat capacity of the heat exchange medium, △T is the inlet and outlet temperature difference of the temperature control structure, and ρ is the density of the heat exchange medium;

[0031] The heat generation power in the supercharging state, the inlet flow rate of the temperature control structure, the supercharging cooling temperature threshold and the suitable operating temperature of the battery pack are used as simulation input parameters. The simulation software is run to simulate the flow process of the heat exchange medium in the liquid cooling plate and the heat exchange process between the battery cell and the heat exchange medium, and a thermal simulation cloud map of each liquid cooling plate area is generated.

[0032] On the basis of the above technical solution, preferably, the step S3 further includes constructing a prediction equation for the length of the choke strip, which includes the following sub-steps:

[0033] Using simulation software to simulate the thermal simulation cloud map under different baffle bar lengths, and extracting the heat dissipation performance index of the liquid cooling plate from the thermal simulation cloud map, wherein the heat dissipation performance index includes temperature gradient and temperature uniformity;

[0034] The heat dissipation performance index under different choke bar lengths is used to construct a data set. The heat dissipation performance index and the choke bar length are fitted according to the data set to construct a choke bar length prediction equation, which is expressed as follows:

[0035] G=c1L 2 +c2L+c3;

[0036] Where G is the heat dissipation performance of the liquid cooling plate, c1, c2 and c3 are the fitting coefficients, and L is the length of different flow control bars.

[0037] On the basis of the above technical solution, preferably, the step S3, according to the thermal simulation cloud map of each liquid cooling plate, respectively adjusts the length of the corresponding flow blocking bar to make the temperature distribution on each liquid cooling plate uniform, and determines the final flow blocking bar length of each liquid cooling plate, including the following sub-steps:

[0038] According to the thermal simulation cloud map of each liquid cooling plate, the heat dissipation performance index of the corresponding liquid cooling plate is obtained respectively;

[0039] According to the prediction equation of the choke bar length and the heat dissipation performance index of the corresponding liquid cooling plate, the length of the choke bar in each liquid cooling plate is calculated and adjusted respectively to make the temperature distribution on each liquid cooling plate uniform and determine the final choke bar length of each liquid cooling plate.

[0040] On the basis of the above technical solution, preferably, the temperature control structure model is simulated based on the adjusted temperature control structure model in step S4, the apertures of the water inlet and the water outlet of each liquid cooling plate are adjusted, and the optimal aperture combination for keeping the temperature balanced is found to obtain the corresponding flow curve, which includes the following sub-steps:

[0041] Re-import the temperature control structure model after adjusting the length of the choke bar into the simulation software;

[0042] Preset the aperture range thresholds of the water inlet and outlet, define the pressure drop range of the temperature control structure, change the aperture sizes of the water inlet and outlet, and obtain the flow curves under different aperture sizes through simulation;

[0043] According to the influence of different aperture sizes on flow rate and the changing trend of flow rate with pressure drop, the optimal aperture combination to keep the temperature balanced is found, the aperture sizes of the water inlet and outlet of each liquid cooling plate are determined, and the corresponding flow curve is obtained.

[0044] On the basis of the above technical solution, preferably, in step S6, based on the final temperature control structure model, the battery pack temperature control strategy under different working conditions is set to control the thermal management of the battery pack, wherein the battery pack includes slow charging and driving cooling conditions, super charging cooling conditions, driving and slow charging heating conditions, super charging heating conditions, super charging uniform heating conditions and slow charging and driving uniform heating conditions;

[0045] Under slow charging and driving cooling conditions, the corresponding battery pack control strategy is:

[0046] When the cell's maximum temperature T max ≥35℃ and the average temperature of the battery cell is T avg When the temperature is ≥32.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0047] If the inlet water temperature is ≥25°C, the cooling mode is turned on, the inlet flow rate of the heat exchange medium is set to 15L / min, and the cooling water temperature is set to 20°C;

[0048] If the inlet water temperature is ≤15℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the cooling water temperature to the inlet temperature value;

[0049] If the inlet water temperature is between 15 and 25°C, if the current mode is closed, the circulation mode is turned on and the inlet flow rate of the heat exchange medium is set to 15L / min, otherwise the previous stage mode is maintained;

[0050] If the maximum temperature of the battery cell Tmax≤32℃ or Tavg≤29.5℃, select the shutdown mode, otherwise keep the previous mode;

[0051] Under supercharge cooling conditions, the corresponding battery pack control strategy is:

[0052] When Tmax≥30℃ and the average temperature of the battery cell Tavg≥27.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0053] If the inlet water temperature is ≥25℃, turn on the cooling mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to 18℃;

[0054] If the inlet water temperature is ≤15℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to the inlet temperature value;

[0055] If the inlet water temperature is between 15 and 25°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 20L / min, otherwise keep the previous stage mode;

[0056] If the maximum temperature of the battery cell is ≤25℃ or the average temperature of the battery cell is ≤22.5℃, select the shutdown mode, otherwise keep the previous mode;

[0057] Under driving and slow charging and heating conditions, the corresponding battery pack control strategy is:

[0058] When the minimum cell temperature T min ≤0℃ and the average temperature of the battery cell is T avg When the temperature is ≤-2.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0059] If the inlet water temperature is ≤40℃, turn on the heating mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the heating water temperature to 45℃;

[0060] If the inlet water temperature is between 35°C and 50°C, the circulation mode is turned on, the inlet flow rate of the heat exchange medium is set to 15L / min, and the water temperature is set to the inlet temperature value;

[0061] If the inlet water temperature is between 40 and 50°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 15L / min, otherwise keep the mode of the previous stage;

[0062] If the minimum cell temperature T min ≥5℃ or the average temperature of the battery cell T avg ≥7.5℃, select the shutdown mode, otherwise keep the previous mode;

[0063] Under the supercharging heating condition, the corresponding battery pack control strategy is:

[0064] When the minimum cell temperature T min≤15℃ and the average temperature of the battery cell T avg When the temperature is ≤17.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0065] If the inlet water temperature is ≤40℃, turn on the heating mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the heating water temperature to 45℃;

[0066] If the inlet water temperature is ≥50℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to the inlet temperature value;

[0067] If the inlet water temperature is between 40 and 50°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 20L / min, otherwise keep the mode of the previous stage;

[0068] If the minimum cell temperature T min ≥20℃ or the average temperature of the battery cell T avg ≥22.5℃, select the shutdown mode, otherwise keep the previous mode;

[0069] Under the supercharging and uniform heating conditions, the corresponding battery pack control strategy is:

[0070] When the cell's maximum temperature T max -Minimum cell temperature T min ≥8℃ and the maximum cell temperature T max ≤25℃ and the minimum cell temperature T min When the temperature is ≥15℃, start the circulation mode and set the inlet flow rate of the heat exchange medium to 15L / min;

[0071] When the cell's maximum temperature T max -Minimum cell temperature T min ≤3℃ or the minimum cell temperature T min <15℃ or the maximum temperature of the battery cell T max When the temperature is >25℃, exit the circulation mode;

[0072] Under slow charging and driving uniform heating conditions, the corresponding battery pack control strategy is:

[0073] When the cell's maximum temperature T max -Minimum cell temperature T min ≥5℃ and the maximum cell temperature T max ≤35℃ and the minimum cell temperature T min When the temperature is ≥0℃, the circulation mode is turned on and the inlet flow rate of the heat exchange medium is set to 15L / min;

[0074] When the cell's maximum temperature T max -Minimum cell temperature T min ≤3℃ or the minimum cell temperature Tmin <0℃ or the maximum temperature of the battery cell T max When the temperature is higher than 35℃, the circulation mode will be exited.

[0075] In a second aspect, the present invention further provides a thermal management control system for a CTP battery pack, the system comprising:

[0076] The initial model building module is used to build a temperature control structure model of the CTP battery pack. The temperature control structure model includes a number of liquid cooling plates. Each liquid cooling plate is provided with a flow-blocking bar. The flow-blocking bar is used to change the direction of the heat exchange medium so that the flow channel in each liquid cooling plate forms a reciprocating zigzag water jacket circulation. The initial length of the flow-blocking bar and the initial aperture of the water inlet and outlet of each liquid cooling plate are preset;

[0077] The simulation module is used to obtain the parameter data of the CTP battery pack that triggers the temperature control to start in the continuous overcharging state, simulate the temperature control structure model according to the parameter data, and obtain the thermal simulation cloud map of each liquid cooling plate area;

[0078] The first adjustment module is used to adjust the length of the corresponding flow blocking bar according to the thermal simulation cloud map of each liquid cooling plate, so that the temperature distribution on each liquid cooling plate is uniform, and the final flow blocking bar length of each liquid cooling plate is determined;

[0079] The second adjustment module is used to simulate the temperature control structure model based on the adjusted temperature control structure model, adjust the apertures of the water inlet and outlet of each liquid cooling plate, find the optimal aperture combination to keep the temperature balanced, and obtain the corresponding flow curve;

[0080] A model determination module is used to form a final temperature control structure model of the CTP battery pack according to the final baffle length and optimal aperture combination of each liquid cooling plate;

[0081] The temperature control strategy module is used to set the battery pack temperature control strategy under different working conditions based on the final temperature control structure model to control the thermal management of the battery pack.

[0082] The thermal management control method and system of the CTP battery pack of the present invention have the following beneficial effects compared with the prior art:

[0083] (1) By constructing the temperature control structure model of the CTP battery pack and its control strategy, the length of the flow-blocking bar and the inlet and outlet apertures can be adjusted according to the simulation, which can optimize the flow path and flow rate of the coolant in the liquid cooling plate, improve the temperature distribution of the battery pack, avoid the occurrence of local overheating or overcooling, and thus significantly improve the thermal management performance of the battery pack.

[0084] (2) By constructing a prediction equation for the length of the choke bar, the optimal length of the choke bar can be quickly determined, which greatly shortens the design cycle and improves the design efficiency. After adjusting the length of the choke bar, the heat dissipation performance of the liquid cooling plate can be significantly improved.

[0085] (3) By optimizing the aperture size of the water inlet and outlet of the liquid cooling plate, temperature balance and efficient heat dissipation performance can be achieved, thereby improving the stability and efficiency of the entire heat exchange system;

[0086] (4) The battery pack temperature control strategy set up realizes precise management of the battery pack temperature through precise temperature monitoring, reasonable temperature control mode selection, and effective heat exchange medium control, thereby optimizing battery performance, ensuring battery safety, and improving the energy efficiency of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0088] Figure 1 It is a flow chart of the thermal management control method of the CTP battery pack of the present invention;

[0089] Figure 2 A three-dimensional diagram of a temperature control structure model of a thermal management control method for a CTP battery pack of the present invention;

[0090] Figure 3 A three-dimensional diagram of a liquid cooling plate of a temperature control structure model of a thermal management control method for a CTP battery pack of the present invention;

[0091] Figure 4 A three-dimensional diagram of the connection structure of the liquid cooling plate, the composite material strip and the thermal conductive adhesive layer of the temperature control structure model of the thermal management control method of the CTP battery pack of the present invention;

[0092] Figure 5 A cross-sectional view of a liquid cooling plate of a temperature control structure model of a thermal management control method for a CTP battery pack of the present invention;

[0093] Figure 6 A flow distribution diagram of the thermal management control method of a CTP battery pack of the present invention;

[0094] Figure 7 This is a 5C supercharge performance test diagram of the thermal management control method of the CTP battery pack of the present invention;

[0095] Figure 8This is a 4C discharge performance test diagram of the thermal management control method of the CTP battery pack of the present invention. DETAILED DESCRIPTION

[0096] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0097] like Figure 1 As shown, a thermal management control method for a CTP battery pack of the present invention is characterized in that the method comprises the following steps:

[0098] S1, construct a temperature control structure model of the CTP battery pack, the temperature control structure model includes a plurality of liquid cooling plates 1, each of which is provided with a flow blocking bar 11, the flow blocking bar 11 is used to change the direction of the heat exchange medium so that the flow channel in each liquid cooling plate 1 forms a reciprocating zigzag water jacket circulation, and the initial length of the flow blocking bar 11 and the initial aperture of the water inlet 101 and the water outlet 102 of each liquid cooling plate 1 are preset.

[0099] It should be noted that during the design of the CTP battery pack, it is necessary to arrange a battery management system, temperature sensors, water inlets, water outlets, current collectors, water cooling plates, thermal conductive layers, etc.; when the temperature of the battery cell rises sharply during the charging and discharging process, the temperature sensor arranged on the top of the battery cell monitors the temperature of each battery cell in the whole pack in real time. When the highest temperature reaches the threshold set by the battery management system, the water pump system on the vehicle side responds by opening the water inlet and outlet to allow the coolant to flow in. Through the settings of different temperatures and different flow rates, the appropriate coolant flows from the current collector at the front end of the water cooling system to the water cooling plate with a special flow channel for flow distribution to heat or cool the battery cell, so that the battery cell and battery pack can enter the most suitable temperature range in time during operation.

[0100] like Figure 2 As shown, the temperature control structure in this embodiment also includes a total water inlet pipeline 2 and a total water outlet pipeline 3, wherein a plurality of liquid cooling plates 1 are arranged in sequence along the width direction, and the battery cells are abutted between two adjacent liquid cooling plates 1, and each liquid cooling plate 1 is provided with a water inlet 101 and a water outlet 102; the water inlet 101 of each liquid cooling plate 1 is connected to the total water inlet pipeline 2, and is used to provide heat exchange medium to the liquid cooling plate 1, and the water outlet 102 of each liquid cooling plate 1 is connected to the total water outlet pipeline 3, and is used for the circulation of heat exchange medium in the liquid cooling plate 1; the water inlet end of the total water inlet pipeline 2 and the water outlet end of the total water outlet pipeline 3 are arranged on the same side.

[0101] It should be noted that the entire temperature control structure adopts a full parallel design from the front to the back liquid cooling plate. The total water inlet pipe 2 and the total water outlet pipe 3 are both on a single side of the liquid cooling plate, so that the assembly pipeline area is all on a single collector of the liquid cooling plate. The single collector is processed by an integrated machine with high precision, which solves the problem of high difficulty requirements for pipe crimping process due to entry and exit from both sides. At the same time, it is conducive to optimizing the internal spatial layout of the battery pack, reducing the space occupied by pipelines, and improving the energy density of the battery pack, so that when maintenance and overhaul are required, the total water inlet pipe 2 and the total water outlet pipe 3 can be more conveniently approached and operated, reducing maintenance costs and time.

[0102] like Figure 4 As shown, in addition, the temperature control structure in this embodiment also includes a plurality of composite material strips 4 and a thermal conductive adhesive layer 5, wherein symmetrically arranged composite material strips 4 are provided on both sides of each liquid cooling plate 1, and a thermal conductive adhesive layer 5 is provided between two corresponding composite material strips 4 on the same side, and the battery cell is abutted against the composite material strip 4 through the thermal conductive adhesive layer 5, and the thermal conductive adhesive layer 5 serves as a heat exchange and heat conductive medium for the battery cell.

[0103] It should be noted that during the process of directly gluing the bottom of the CTP battery cell side cooling structure to the bottom of the box body, the battery cell expansion cannot be effectively absorbed due to the lack of end plates to fix the battery cell sides and limited space. Especially at the end of the battery cell life, the battery cell expansion can reach 2% or more, and the expansion force can reach more than 60000N, which has a significant impact on the safety and performance of the battery pack and the entire vehicle. In this embodiment, the composite material strip 4 is formed by superimposing PC strips and PU foam. During the battery cell stacking process, the PC strips can ensure the minimum glue pressing amount while ensuring the consistency of the Block stacking size. In addition, the PU foam can effectively absorb the expansion of the battery cell during the battery cell expansion process.

[0104] like Figure 3 and Figure 5As shown, in addition, the liquid cooling plate 1 in this embodiment also includes a first harmonica tube 12, a second harmonica tube 13, a first current collector 14, a second current collector 15 and a crushing bar 16, wherein the first harmonica tube 12 and the second harmonica tube 13 are respectively arranged on both sides of the crushing bar 16, and a plurality of parallel flow channels are arranged in the first harmonica tube 12 and the second harmonica tube 13; the number of the blocking bar 11 is two, and the two blocking bars 11 are respectively arranged on both sides of the second harmonica tube 13, and are arranged in a central symmetrical manner, so that the parallel flow channels of the heat exchange medium in the second harmonica tube 13 form a reciprocating zigzag shape. flow; the first current collector 14 and the second current collector 15 are respectively arranged on both sides of the first harmonica tube 12 and the second harmonica tube 13, the water inlet 101 and the water outlet 102 are both opened on the first current collector 14, the water inlet 101 is connected with the liquid inlet end of the first harmonica tube 12, the liquid outlet end of the first harmonica tube 12 is connected with one end of the second current collector 15, the other end of the second current collector 15 is connected with the liquid inlet end of the second harmonica tube 13, the liquid outlet end of the second harmonica tube 13 is connected with the water outlet 102, so as to make the flow channel in each liquid cooling plate 1 form a reciprocating zigzag water jacket circulation.

[0105] It should be noted that a crushing stop bar 16 is provided between the first harmonica tube 12 and the second harmonica tube 13. Both the DC channel and the bending channel are parallelograms. When the parallelogram channel is squeezed by the expansion force of the battery cell, the flow channel will be deformed. When the deformed area reaches the crushing stop bar 16, since the crushing stop bar 16 is solid, when the battery cell expands to this point, the first harmonica tube 12 and the second harmonica tube 13 will not be further crushed, thereby preventing the liquid cooling plate from being crushed due to the expansion of the battery cell at the end of its life, thereby improving the stability of the cooling structure.

[0106] Specifically, the material of the crushing stop bar 16 in this embodiment is preferably aluminum, and the solid structure of the crushing stop bar 16 is the same as the material of the liquid cooling plate body, and the crushing stop bar 16 and the first harmonica tube 12 and the second harmonica tube 13 are an integrally processed structure.

[0107] Among them, a number of parallel flow channels are provided in the first harmonica tube 12 and the second harmonica tube 13, which is conducive to reducing the resistance to fluid flow. Compared with vertical or horizontal partitions, inclined partitions can better guide the flow direction of the fluid and reduce eddy and turbulent phenomena in the flow process of the fluid, which is conducive to reducing the flow resistance of the fluid and improving the efficiency of the entire liquid cooling system.

[0108] The flow-blocking bar 11 in this embodiment is used to change the direction of the heat exchange medium, so that the flow channel in each liquid cooling plate 1 forms a reciprocating zigzag water jacket circulation, and the inner cavity of the second harmonica tube 13 is divided into a reciprocating zigzag flow channel, which not only increases the flow path length of the fluid in the tube, but also allows the fluid to change direction multiple times during the flow process. In addition, combined with the second current collector 15 and the first harmonica tube 12, the coating formed on the flow channel in the second harmonica tube 13 forms a reciprocating zigzag water jacket circulation, thereby enhancing the heat exchange effect between the fluid and the tube wall.

[0109] This embodiment adopts adjacent cold and hot flow channels. The liquid inlet flow channel of the second current collector 15 is the coldest area of ​​the flow channel in the cold plate, and the outlet flow channel of the first current collector 14 is the hottest area. The coldest area and the hottest area are arranged adjacent to each other, and thus will affect each other. The comprehensive temperature prevents the battery cell from being overcooled or overheated, and the temperature difference performance is better, thereby improving the heat exchange effect.

[0110] It can be understood that the width of the flow-blocking bar 11 matches the width of the second harmonica pipe 2, which effectively ensures the closed flow channel and prevents leakage of the fluid in the flow channel.

[0111] S2, obtaining parameter data of the CTP battery pack triggering the temperature control to be turned on in the continuous overcharging state, simulating the temperature control structure model according to the parameter data, and obtaining the thermal simulation cloud map of each liquid cooling plate area.

[0112] Step S2 includes the following sub-steps:

[0113] Get the heat generation power of the CTP battery pack under continuous overcharge state, the expression is:

[0114] P=I 2 *R

[0115] In the formula, P is heating power, I is peak current, and R is the internal resistance of the battery cell;

[0116] Preset the supercharge cooling temperature threshold and the suitable working temperature of the battery pack, use the supercharge cooling temperature threshold as the inlet temperature of the temperature control structure, and use the suitable working temperature of the battery pack as the outlet temperature of the temperature control structure;

[0117] According to the preset supercharge cooling temperature threshold and the suitable operating temperature of the battery pack, the temperature difference between the inlet and outlet of the temperature control structure is calculated;

[0118] Select the heat exchange medium, and calculate the inlet flow rate of the temperature control structure according to the heat generation power, parameters of the heat exchange medium and temperature difference under the overcharge state. The expression is:

[0119] V q =P / (C*ρ*△T)

[0120] Where V qis the inlet flow rate of the temperature control structure, P is the heat generation power under supercharging state, C is the specific heat capacity of the heat exchange medium, △T is the inlet and outlet temperature difference of the temperature control structure, and ρ is the density of the heat exchange medium;

[0121] The heat generation power in the supercharging state, the inlet flow rate of the temperature control structure, the supercharging cooling temperature threshold and the suitable operating temperature of the battery pack are used as simulation input parameters. The simulation software is run to simulate the flow process of the heat exchange medium in the liquid cooling plate 1 and the heat exchange process between the battery cell and the heat exchange medium, and a thermal simulation cloud map of each liquid cooling plate 1 is generated.

[0122] It should be noted that based on the principles of thermodynamics and fluid mechanics, the heat generation power of the CTP battery pack under continuous overcharging is calculated, and the overcharging cooling temperature threshold and the appropriate operating temperature of the battery pack are preset to determine the inlet and outlet temperature difference and inlet flow rate of the temperature control structure. Then, the simulation software is used to simulate the flow process of the heat exchange medium in the liquid cooling plate and the heat exchange process between the battery cell and the heat exchange medium, and the thermal simulation cloud map of each liquid cooling plate is generated.

[0123] The step S3 also includes constructing a prediction equation for the length of the spoiler strip 11, which includes the following sub-steps:

[0124] The thermal simulation cloud map under different lengths of the flow-blocking bar 11 is simulated by simulation software, and the heat dissipation performance index of the liquid cooling plate 1 is extracted from the thermal simulation cloud map, wherein the heat dissipation performance index includes temperature gradient and temperature uniformity;

[0125] A data set is constructed by using the heat dissipation performance index under different lengths of the choke bar 11. The heat dissipation performance index and the length of the choke bar 11 are fitted according to the data set to construct a prediction equation for the length of the choke bar 11. The expression is:

[0126] G=c1L 2 +c2L+c3;

[0127] Wherein, G is the heat dissipation performance of the liquid cooling plate, c1, c2 and c3 are the coefficients obtained by fitting, and L is the length of different baffle bars 11.

[0128] It should be noted that thermal simulation software is used to simulate the thermal simulation cloud map of the liquid cooling plate under different choke bar lengths, and key heat dissipation performance indicators are extracted from the thermal simulation cloud map. These indicators should be able to fully reflect the heat dissipation effect of the liquid cooling plate. The heat dissipation performance indicators include temperature gradient and temperature uniformity. The temperature gradient indicates how fast the temperature changes on the liquid cooling plate, while the temperature uniformity reflects the degree of proximity of the temperatures of various points on the liquid cooling plate. The heat dissipation performance indicators simulated under different choke bar lengths are combined with the corresponding choke bar lengths to construct a data set. The heat dissipation performance indicators and the choke bar length are fitted according to the data set to obtain the relationship between the heat dissipation performance indicators and the choke bar length, that is, the choke bar 11 length prediction equation.

[0129] S3, according to the thermal simulation cloud map of each liquid cooling plate, respectively adjust the length of the corresponding flow blocking bar 11 to make the temperature distribution on each liquid cooling plate 1 uniform, and determine the final flow blocking bar length of each liquid cooling plate 1.

[0130] Step S3 includes the following sub-steps:

[0131] According to the thermal simulation cloud map of each liquid cooling plate 1, the heat dissipation performance index of the corresponding liquid cooling plate 1 is obtained respectively;

[0132] According to the prediction equation of the length of the baffle bar 11 and the heat dissipation performance index of the corresponding liquid cooling plate, the length of the baffle bar 11 in each liquid cooling plate is calculated and adjusted respectively to make the temperature distribution on each liquid cooling plate 1 uniform, and determine the final length of the baffle bar 11 of each liquid cooling plate 1.

[0133] It should be noted that thermal simulation software is used to perform thermal simulation analysis on each liquid cooling plate, and the thermal simulation cloud map is observed to identify the high-temperature and low-temperature areas on the liquid cooling plate. According to the thermal simulation results, the key heat dissipation performance indicators are extracted, and the preliminary choke bar length is calculated based on the choke bar length prediction equation and the current liquid cooling plate's heat dissipation performance indicators. This length should be able to improve the temperature distribution of the liquid cooling plate and make its temperature distribution more uniform.

[0134] It is understandable that the adjusted spoiler bar length is simulated and verified using thermal simulation software, and the simulation results are observed. If the simulation results do not meet the requirements, the spoiler bar length is further adjusted according to the simulation results, and the simulation verification and iterative adjustment process is repeated until the optimal spoiler bar length is found.

[0135] According to this embodiment, the length of the flow-blocking bars in the liquid cooling plate can be optimized, thereby improving the heat dissipation performance of the liquid cooling plate and ensuring a more uniform temperature distribution of each liquid cooling plate.

[0136] according to Figure 6 As shown, S4, based on the adjusted temperature control structure model, the temperature control structure model is simulated, the apertures of the water inlet 101 and the water outlet 102 of each liquid cooling plate 1 are adjusted, the optimal aperture combination for maintaining a balanced temperature is found, and the corresponding flow curve is obtained.

[0137] Step S4 includes the following sub-steps:

[0138] The temperature control structure model after adjusting the length of the baffle bar 11 is re-imported into the simulation software;

[0139] Preset the aperture range thresholds of the water inlet 101 and the water outlet 102, define the pressure drop range of the temperature control structure, change the aperture sizes of the water inlet 101 and the water outlet 102, and obtain the flow curves under different aperture sizes through simulation;

[0140] According to the influence of different aperture sizes on flow rate and the variation trend of flow rate with pressure drop, the optimal aperture combination to keep the temperature balanced is found, the aperture sizes of the water inlet 101 and the water outlet 102 of each liquid cooling plate are determined, and the corresponding flow curve is obtained.

[0141] It should be noted that the size of the aperture directly determines the flow rate of the coolant. A larger aperture can provide a larger flow rate, but it may also cause an increase in pressure drop. Although a smaller aperture can reduce the pressure drop, it may limit the flow rate and affect the heat dissipation effect. In order to achieve temperature balance, it is necessary to ensure that the coolant is evenly distributed in the liquid cooling plate and takes away enough heat. Therefore, by optimizing the aperture size of the water inlet and outlet, the optimal aperture combination that keeps the temperature balanced can be found. In this embodiment, the simulation software is used to model and simulate the liquid cooling plate, which can simulate the flow curve and temperature distribution under different aperture sizes. Through comparative analysis, the optimal aperture combination can be found to achieve temperature balance and efficient heat dissipation performance.

[0142] In this embodiment, by optimizing the aperture sizes of the water inlet and outlet of the liquid cooling plate, temperature balance and efficient heat dissipation performance can be achieved, thereby improving the stability and efficiency of the entire heat exchange system.

[0143] S5, forming a final temperature control structure model of the CTP battery pack according to the determined final length of the flow blocking bar 11 and the optimal aperture combination of each liquid cooling plate 1.

[0144] S6, based on the final temperature control structure model, sets the battery pack temperature control strategy under different working conditions to control the thermal management of the battery pack.

[0145] Among them, the battery pack includes slow charging and driving cooling conditions, super charging cooling conditions, driving and slow charging heating conditions, super charging heating conditions, super charging uniform heating conditions and slow charging and driving uniform heating conditions;

[0146] Under slow charging and driving cooling conditions, the corresponding battery pack control strategy is:

[0147] When the cell's maximum temperature T max ≥35℃ and the average temperature of the battery cell is T avg When the temperature is ≥32.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0148] If the inlet water temperature is ≥25°C, the cooling mode is turned on, the inlet flow rate of the heat exchange medium is set to 15L / min, and the cooling water temperature is set to 20°C;

[0149] If the inlet water temperature is ≤15℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the cooling water temperature to the inlet temperature value;

[0150] If the inlet water temperature is between 15 and 25°C, if the current mode is closed, the circulation mode is turned on and the inlet flow rate of the heat exchange medium is set to 15L / min, otherwise the previous stage mode is maintained;

[0151] If the maximum temperature of the battery cell Tmax≤32℃ or Tavg≤29.5℃, select the shutdown mode, otherwise keep the previous mode;

[0152] Under supercharge cooling conditions, the corresponding battery pack control strategy is:

[0153] When Tmax≥30℃ and the average temperature of the battery cell Tavg≥27.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0154] If the inlet water temperature is ≥25℃, turn on the cooling mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to 18℃;

[0155] If the inlet water temperature is ≤15℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to the inlet temperature value;

[0156] If the inlet water temperature is between 15 and 25°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 20L / min, otherwise keep the previous stage mode;

[0157] If the maximum temperature of the battery cell is ≤25℃ or the average temperature of the battery cell is ≤22.5℃, select the shutdown mode, otherwise keep the previous mode;

[0158] Under driving and slow charging and heating conditions, the corresponding battery pack control strategy is:

[0159] When the minimum cell temperature T min ≤0℃ and the average temperature of the battery cell is T avg When the temperature is ≤-2.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0160] If the inlet water temperature is ≤40℃, turn on the heating mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the heating water temperature to 45℃;

[0161] If the inlet water temperature is between 35°C and 50°C, the circulation mode is turned on, the inlet flow rate of the heat exchange medium is set to 15L / min, and the water temperature is set to the inlet temperature value;

[0162] If the inlet water temperature is between 40 and 50°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 15L / min, otherwise keep the mode of the previous stage;

[0163] If the minimum cell temperature Tmin ≥5℃ or the average temperature of the battery cell T avg ≥7.5℃, select the shutdown mode, otherwise keep the previous mode;

[0164] Under the supercharging heating condition, the corresponding battery pack control strategy is:

[0165] When the minimum cell temperature T min ≤15℃ and the average temperature of the battery cell T avg When the temperature is ≤17.5℃, the temperature control strategy thermal management is triggered to perform thermal management control;

[0166] If the inlet water temperature is ≤40℃, turn on the heating mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the heating water temperature to 45℃;

[0167] If the inlet water temperature is ≥50℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to the inlet temperature value;

[0168] If the inlet water temperature is between 40 and 50°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 20L / min, otherwise keep the mode of the previous stage;

[0169] If the minimum cell temperature T min ≥20℃ or the average temperature of the battery cell T avg ≥22.5℃, select the shutdown mode, otherwise keep the previous mode;

[0170] Under the supercharging and uniform heating conditions, the corresponding battery pack control strategy is:

[0171] When the cell's maximum temperature T max -Minimum cell temperature T min ≥8℃ and the maximum cell temperature T max ≤25℃ and the minimum cell temperature T min When the temperature is ≥15℃, start the circulation mode and set the inlet flow rate of the heat exchange medium to 15L / min;

[0172] When the cell's maximum temperature T max -Minimum cell temperature T min ≤3℃ or the minimum cell temperature T min <15℃ or the maximum temperature of the battery cell T max When the temperature is >25℃, exit the circulation mode;

[0173] Under slow charging and driving uniform heating conditions, the corresponding battery pack control strategy is:

[0174] When the cell's maximum temperature T max -Minimum cell temperature T min≥5℃ and the maximum cell temperature T max ≤35℃ and the minimum cell temperature T min When the temperature is ≥0℃, the circulation mode is turned on and the inlet flow rate of the heat exchange medium is set to 15L / min;

[0175] When the cell's maximum temperature T max -Minimum cell temperature T min ≤3℃ or the minimum cell temperature T min <0℃ or the maximum temperature of the battery cell T max When the temperature is higher than 35℃, the circulation mode will be exited.

[0176] It should be noted that the battery pack temperature control strategy achieves precise management of the battery pack temperature through precise temperature monitoring, reasonable temperature control mode selection, and effective heat exchange medium control, thereby optimizing battery performance, ensuring battery safety, and improving the energy efficiency of the system.

[0177] according to Figure 7 and Figure 8 As shown, the supercharge test results of the CTP battery pack at room temperature 25℃±2 are as follows: 0%~100% peak current 5C-625A peak power 445kW average current 3.2C-400A average power 286kW, battery cell Tmax=35℃, temperature difference 4℃; 100%~0% peak 5C peak current 4C-515A peak power 320kW average current 3.5C 441A average power 265kW; battery cell Tmax=31℃, temperature difference 3℃

[0178] In a second aspect, the present invention further provides a thermal management control system for a CTP battery pack, the system comprising:

[0179] An initial model building module is used to build a temperature control structure model of a CTP battery pack. The temperature control structure model includes a plurality of liquid cooling plates 1. Each liquid cooling plate 1 is provided with a flow blocking bar 11. The flow blocking bar 11 is used to change the direction of the heat exchange medium so that the flow channel in each liquid cooling plate 1 forms a reciprocating zigzag water jacket circulation. The initial length of the flow blocking bar 11 and the initial aperture of the water inlet 101 and the water outlet 102 of each liquid cooling plate 1 are preset;

[0180] The simulation module is used to obtain the parameter data of the CTP battery pack that triggers the temperature control to start in the continuous overcharging state, simulate the temperature control structure model according to the parameter data, and obtain the thermal simulation cloud map of each liquid cooling plate area;

[0181] The first adjustment module is used to adjust the length of the corresponding flow blocking bar according to the thermal simulation cloud map of each liquid cooling plate, so that the temperature distribution on each liquid cooling plate 1 is uniform, and determine the final flow blocking bar length of each liquid cooling plate 1;

[0182] The second adjustment module is used to simulate the temperature control structure model based on the adjusted temperature control structure model, adjust the apertures of the water inlet 101 and the water outlet 102 of each liquid cooling plate 1, find the optimal aperture combination to keep the temperature balanced, and obtain the corresponding flow curve;

[0183] A model determination module, used to form a final temperature control structure model of the CTP battery pack according to the final length of the flow blocking bar 11 and the optimal aperture combination of each liquid cooling plate 1 determined;

[0184] The temperature control strategy module is used to set the battery pack temperature control strategy under different working conditions based on the final temperature control structure model to control the thermal management of the battery pack.

[0185] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A thermal management control method for a CTP battery pack, characterized in that: The method comprises the following steps: S1, constructing a temperature control structure model of a CTP battery pack, the temperature control structure model comprising a plurality of liquid cooling plates (1), each liquid cooling plate (1) being provided with a flow blocking bar (11), the flow blocking bar (11) being used to change the direction of a heat exchange medium so that a flow channel in each liquid cooling plate (1) forms a reciprocating zigzag water jacket circulation, and the initial length of the flow blocking bar (11) and the initial aperture of the water inlet (101) and the water outlet (102) of each liquid cooling plate (1) are preset; S2, obtaining parameter data of the CTP battery pack triggering the temperature control to start in the continuous overcharging state, simulating the temperature control structure model according to the parameter data, and obtaining the thermal simulation cloud map of each liquid cooling plate area; S3, according to the thermal simulation cloud map of each liquid cooling plate, respectively adjusting the length of the corresponding flow blocking bar (11) to make the temperature distribution on each liquid cooling plate (1) uniform, and determining the final flow blocking bar length of each liquid cooling plate (1); S4, based on the adjusted temperature control structure model, simulating the temperature control structure model, adjusting the apertures of the water inlet (101) and the water outlet (102) of each liquid cooling plate (1), finding the optimal aperture combination for maintaining a balanced temperature, and obtaining a corresponding flow curve; S5, forming a final temperature control structure model of the CTP battery pack according to the final length of the flow blocking bar (11) and the optimal aperture combination of each liquid cooling plate (1) determined; S6, based on the final temperature control structure model, sets the battery pack temperature control strategy under different working conditions to control the thermal management of the battery pack.

2. The thermal management control method of a CTP battery pack according to claim 1, characterized in that: The temperature control structure further comprises a main water inlet pipeline (2) and a main water outlet pipeline (3), wherein: A plurality of liquid cooling plates (1) are arranged in sequence and spaced apart along the width direction thereof, the battery cells are abutted between two adjacent liquid cooling plates (1), and each liquid cooling plate (1) is provided with a water inlet (101) and a water outlet (102); The water inlet (101) of each liquid cooling plate (1) is connected to the main water inlet pipeline (2) for supplying heat exchange medium into the liquid cooling plate (1), and the water outlet (102) of each liquid cooling plate (1) is connected to the main water outlet pipeline (3) for circulation of heat exchange medium in the liquid cooling plate (1); The water inlet end of the main water inlet pipeline (2) and the water outlet end of the main water outlet pipeline (3) are arranged on the same side.

3. The thermal management control method of a CTP battery pack according to claim 2, characterized in that: The temperature control structure further comprises a plurality of composite material strips (4) and a thermally conductive adhesive layer (5), wherein both sides of each liquid cooling plate (1) are provided with symmetrically arranged composite material strips (4), a thermally conductive adhesive layer (5) is arranged between two corresponding composite material strips (4) on the same side, the battery core is in contact with the composite material strips (4) via the thermally conductive adhesive layer (5), and the thermally conductive adhesive layer (5) serves as a heat exchange heat conduction medium for the battery core.

4. The thermal management control method of a CTP battery pack according to claim 3, characterized in that: The liquid cooling plate (1) further comprises a first harmonica tube (12), a second harmonica tube (13), a first current collector (14), a second current collector (15) and a crushing stop bar (16), wherein: The first harmonica pipe (12) and the second harmonica pipe (13) are respectively arranged on both sides of the crushing stop bar (16), and a plurality of parallel flow channels are arranged in the first harmonica pipe (12) and the second harmonica pipe (13); The number of the flow-blocking bars (11) is two, and the two flow-blocking bars (11) are respectively arranged on both sides of the second harmonica tube (13) and are arranged symmetrically to the center, so that the heat exchange medium forms a reciprocating zigzag flow in the parallel flow channels in the second harmonica tube (13); The first current collector (14) and the second current collector (15) are respectively arranged on both sides of the first harmonica tube (12) and the second harmonica tube (13); the water inlet (101) and the water outlet (102) are both provided on the first current collector (14); the water inlet (101) is connected to the liquid inlet end of the first harmonica tube (12); the liquid outlet end of the first harmonica tube (12) is connected to one end of the second current collector (15); the other end of the second current collector (15) is connected to the liquid inlet end of the second harmonica tube (13); the liquid outlet end of the second harmonica tube (13) is connected to the water outlet (102), so as to enable the flow channel in each liquid cooling plate (1) to form a reciprocating zigzag water jacket circulation.

5. The thermal management control method of a CTP battery pack according to claim 4, characterized in that: The step S2 includes obtaining parameter data for triggering temperature control of the CTP battery pack under continuous overcharging, simulating the temperature control structure model according to the parameter data, and obtaining a thermal simulation cloud map of each liquid cooling plate area, including the following sub-steps: Get the heat generation power of the CTP battery pack under continuous overcharge state, the expression is: P=I 2 *R In the formula, P is heating power, I is peak current, and R is the internal resistance of the battery cell; Preset the supercharge cooling temperature threshold and the suitable working temperature of the battery pack, use the supercharge cooling temperature threshold as the inlet temperature of the temperature control structure, and use the suitable working temperature of the battery pack as the outlet temperature of the temperature control structure; According to the preset supercharge cooling temperature threshold and the suitable operating temperature of the battery pack, the temperature difference between the inlet and outlet of the temperature control structure is calculated; Select the heat exchange medium, and calculate the inlet flow rate of the temperature control structure according to the heat generation power, parameters of the heat exchange medium and temperature difference under the overcharge state. The expression is: V q NP / (C*ρ*△T) Where V q is the inlet flow rate of the temperature control structure, P is the heat generation power under supercharging state, C is the specific heat capacity of the heat exchange medium, △T is the inlet and outlet temperature difference of the temperature control structure, and ρ is the density of the heat exchange medium; The heat generation power in the supercharging state, the inlet flow rate of the temperature control structure, the supercharging cooling temperature threshold and the suitable operating temperature of the battery pack are used as simulation input parameters, and the simulation software is run to simulate the flow process of the heat exchange medium in the liquid cooling plate (1) and the heat exchange process between the battery cell and the heat exchange medium, thereby generating a thermal simulation cloud map of each liquid cooling plate (1).

6. The thermal management control method of a CTP battery pack according to claim 5, characterized in that: The step S3 also includes constructing a prediction equation for the length of the choke strip (11), which includes the following sub-steps: Using simulation software to simulate thermal simulation cloud maps under different lengths of the flow-blocking strip (11), and extracting heat dissipation performance indicators of the liquid cooling plate (1) from the thermal simulation cloud map, wherein the heat dissipation performance indicators include temperature gradient and temperature uniformity; A data set is constructed by using heat dissipation performance indicators under different lengths of the choke bar (11). The heat dissipation performance indicators and the length of the choke bar (11) are fitted according to the data set to construct a prediction equation for the length of the choke bar (11). The expression is: G=c1L 2 +c2L+c3; Where G is the heat dissipation performance of the liquid cooling plate, c1, c2 and c3 are the coefficients obtained by fitting, and L is the length of different baffle bars (11).

7. The thermal management control method of a CTP battery pack according to claim 6, characterized in that: In step S3, according to the thermal simulation cloud map of each liquid cooling plate (1), the length of the corresponding flow blocking bar (11) is adjusted respectively to make the temperature distribution on each liquid cooling plate (1) uniform, and the final length of the flow blocking bar (11) of each liquid cooling plate (1) is determined, which includes the following sub-steps: According to the thermal simulation cloud map of each liquid cooling plate (1), the heat dissipation performance index of the corresponding liquid cooling plate (1) is obtained respectively; According to the prediction equation of the length of the flow-blocking bar (11) and the heat dissipation performance index of the corresponding liquid cooling plate, the length of the flow-blocking bar (11) in each liquid cooling plate is calculated and adjusted respectively, so that the temperature distribution on each liquid cooling plate (1) is uniform, and the final length of the flow-blocking bar (11) of each liquid cooling plate (1) is determined.

8. The thermal management control method of a CTP battery pack according to claim 7, characterized in that: The step S4 is based on the adjusted temperature control structure model, simulating the temperature control structure model, adjusting the apertures of the water inlet (101) and the water outlet (102) of each liquid cooling plate (1), finding the optimal aperture combination for maintaining a balanced temperature, and obtaining a corresponding flow curve, including the following sub-steps: Re-importing the temperature control structure model after adjusting the length of the flow-blocking bar (11) into the simulation software; Preset the aperture range thresholds of the water inlet (101) and the water outlet (102), define the pressure drop range of the temperature control structure, change the aperture sizes of the water inlet (101) and the water outlet (102), and obtain flow curves under different aperture sizes through simulation; According to the influence of different aperture sizes on flow rate and the variation trend of flow rate with pressure drop, the optimal aperture combination for maintaining temperature balance is found, the aperture sizes of the water inlet (101) and the water outlet (102) of each liquid cooling plate are determined, and the corresponding flow curve is obtained.

9. The thermal management control method of a CTP battery pack according to claim 8, characterized in that: In step S6, based on the final temperature control structure model, the battery pack temperature control strategy under different working conditions is set to control the thermal management of the battery pack, wherein the battery pack includes slow charging and driving cooling conditions, super charging cooling conditions, driving and slow charging heating conditions, super charging heating conditions, super charging uniform heating conditions, and slow charging and driving uniform heating conditions; Under slow charging and driving cooling conditions, the corresponding battery pack control strategy is: When the cell's maximum temperature T max ≥35℃ and the average temperature of the battery cell is T avg When the temperature is ≥32.5℃, the temperature control strategy thermal management is triggered to perform thermal management control; If the inlet water temperature is ≥25℃, the cooling mode is turned on, the inlet flow rate of the heat exchange medium is set to 15L / min, and the cooling water temperature is set to 20℃; If the inlet water temperature is ≤15℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the cooling water temperature to the inlet temperature value; If the inlet water temperature is between 15 and 25°C, if the current mode is closed, the circulation mode is turned on and the inlet flow rate of the heat exchange medium is set to 15L / min, otherwise the previous stage mode is maintained; If the maximum temperature of the battery cell Tmax≤32℃ or Tavg≤29.5℃, select the shutdown mode, otherwise keep the previous mode; Under supercharge cooling conditions, the corresponding battery pack control strategy is: When Tmax≥30℃ and the average temperature of the battery cell Tavg≥27.5℃, the temperature control strategy thermal management is triggered to perform thermal management control; If the inlet water temperature is ≥25℃, turn on the cooling mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to 18℃; If the inlet water temperature is ≤15℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to the inlet temperature value; If the inlet water temperature is between 15 and 25°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 20L / min, otherwise keep the previous stage mode; If the maximum temperature of the battery cell is ≤25℃ or the average temperature of the battery cell is ≤22.5℃, select the shutdown mode, otherwise keep the previous mode; Under driving and slow charging and heating conditions, the corresponding battery pack control strategy is: When the minimum cell temperature T min ≤0℃ and the average temperature of the battery cell is T avg When the temperature is ≤-2.5℃, the temperature control strategy thermal management is triggered to perform thermal management control; If the inlet water temperature is ≤40℃, turn on the heating mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the heating water temperature to 45℃; If the inlet water temperature is between 35°C and 50°C, the circulation mode is turned on, the inlet flow rate of the heat exchange medium is set to 15L / min, and the water temperature is set to the inlet temperature value; If the inlet water temperature is between 40 and 50°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 15L / min, otherwise keep the mode of the previous stage; If the minimum cell temperature T min ≥5℃ or the average temperature of the battery cell T avg ≥7.5℃, select the shutdown mode, otherwise keep the previous mode; Under the supercharging heating condition, the corresponding battery pack control strategy is: When the minimum cell temperature T min ≤15℃ and the average temperature of the battery cell T avg When the temperature is ≤17.5℃, the temperature control strategy thermal management is triggered to perform thermal management control; If the inlet water temperature is ≤40℃, turn on the heating mode, set the inlet flow rate of the heat exchange medium to 15L / min, and the heating water temperature to 45℃; If the inlet water temperature is ≥50℃, start the circulation mode, set the inlet flow rate of the heat exchange medium to 20L / min, and the cooling water temperature to the inlet temperature value; If the inlet water temperature is between 40 and 50°C, if the current mode is closed, turn on the circulation mode and set the inlet flow rate of the heat exchange medium to 20L / min, otherwise keep the mode of the previous stage; If the minimum cell temperature T min ≥20℃ or the average temperature of the battery cell T avg ≥22.5℃, select the shutdown mode, otherwise keep the previous mode; Under the supercharging and uniform heating conditions, the corresponding battery pack control strategy is: When the cell's maximum temperature T max -Minimum cell temperature T min ≥8℃ and the maximum cell temperature T max ≤25℃ and the minimum cell temperature T min When the temperature is ≥15℃, start the circulation mode and set the inlet flow rate of the heat exchange medium to 15L / min; When the cell's maximum temperature T max -Minimum cell temperature T min ≤3℃ or the minimum cell temperature T min <15℃ or the maximum temperature of the battery cell T max When the temperature is >25℃, exit the circulation mode; Under slow charging and driving uniform heating conditions, the corresponding battery pack control strategy is: When the cell's maximum temperature T max -Minimum cell temperature T min ≥5℃ and the maximum cell temperature T max ≤35℃ and the minimum cell temperature T min When the temperature is ≥0℃, the circulation mode is turned on and the inlet flow rate of the heat exchange medium is set to 15L / min; When the cell's maximum temperature T max -Minimum cell temperature T min ≤3℃ or the minimum cell temperature T min <0℃ or the maximum temperature of the battery cell T max When the temperature is higher than 35℃, the circulation mode will be exited.

10. A thermal management control system for a CTP battery pack, characterized in that: The system comprises: An initial model construction module is used to construct a temperature control structure model of a CTP battery pack, the temperature control structure model comprising a plurality of liquid cooling plates (1), each liquid cooling plate (1) being provided with a flow blocking bar (11), the flow blocking bar (11) being used to change the direction of a heat exchange medium so that a flow channel in each liquid cooling plate (1) forms a reciprocating zigzag water jacket circulation, and the initial length of the flow blocking bar (11) and the initial aperture of the water inlet (101) and the water outlet (102) of each liquid cooling plate (1) are preset; The simulation module is used to obtain the parameter data of the CTP battery pack that triggers the temperature control to start in the continuous overcharging state, simulate the temperature control structure model according to the parameter data, and obtain the thermal simulation cloud map of each liquid cooling plate area; A first adjustment module is used to adjust the length of the corresponding flow blocking bar according to the thermal simulation cloud map of each liquid cooling plate, so that the temperature distribution on each liquid cooling plate (1) is uniform, and the final flow blocking bar length of each liquid cooling plate (1) is determined; A second adjustment module is used to simulate the temperature control structure model based on the adjusted temperature control structure model, adjust the apertures of the water inlet (101) and the water outlet (102) of each liquid cooling plate (1), find the optimal aperture combination for maintaining a balanced temperature, and obtain a corresponding flow curve; A model determination module, used to form a final temperature control structure model of the CTP battery pack according to the final length of the flow blocking bar (11) and the optimal aperture combination determined for each liquid cooling plate (1); The temperature control strategy module is used to set the battery pack temperature control strategy under different working conditions based on the final temperature control structure model to control the thermal management of the battery pack.

Images