Battery module and temperature control method thereof

Abstract

The application discloses a battery module and a temperature control method, the battery module comprises a shell, a battery cell assembly and a cooling circulation system; a containing cavity is formed in the shell, a partition is arranged in the containing cavity, the containing cavity is divided into a first sub-cavity and a second sub-cavity; the battery cell assembly is arranged in the containing cavity, the battery cell assembly comprises a plurality of battery cells, the plurality of battery cells are distributed in the first sub-cavity and the second sub-cavity; the cooling circulation system comprises a liquid cooling circuit and an air cooling circuit, the liquid cooling circuit is provided with a liquid inlet and a liquid outlet, the liquid inlet is formed in the first sub-cavity, the liquid outlet is formed in the second sub-cavity, the air cooling circuit is provided with an air inlet and an air outlet, the air inlet is formed in the second sub-cavity, and the air outlet is formed in the first sub-cavity. The application aims at solving the problem that the existing cooling system is not uniform in cooling the battery module.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more specifically to a battery module and its temperature control method. Background Technology

[0002] Temperature is a crucial factor affecting battery performance and lifespan. During charging and discharging, battery modules inevitably generate heat. Therefore, in the battery industry, liquid cooling plates are typically installed within the battery module to improve heat dissipation efficiency. A battery module usually contains multiple cell groups, each composed of multiple cells. Current technology primarily uses liquid cooling units to control the temperature of the cell groups. The typical supply water temperature of these liquid cooling units is 15-120℃, resulting in a low inlet temperature. During operation, the cells are generally set to 30℃ for intelligent temperature control. The problem is that the temperature difference between the coolant inlet and outlet of the cells leads to a greater temperature difference between the cells, affecting the consistency of cell performance and ultimately impacting cell lifespan. Summary of the Invention

[0003] The main objective of this invention is to propose a battery module and a temperature control method, which aims to solve the problem of uneven cooling of the battery module by existing cooling systems.

[0004] To achieve the above objectives, the present invention provides a battery module comprising:

[0005] A housing having a receiving cavity formed therein, the receiving cavity being provided with a partition that divides the receiving cavity into a first sub-cavity and a second sub-cavity;

[0006] A battery cell assembly, disposed within the receiving cavity, the battery cell assembly comprising a plurality of battery cells distributed in the first sub-cavity and the second sub-cavity; and

[0007] The cooling circulation system includes a liquid cooling circuit and an air cooling circuit. The liquid cooling circuit is provided with a liquid inlet and a liquid outlet. The liquid inlet is formed in a first compartment, and the liquid outlet is formed in a second compartment. The air cooling circuit is provided with an air inlet and an air outlet. The air inlet is formed in the second compartment, and the air outlet is formed in the first compartment.

[0008] Optionally, a liquid cooling plate is provided inside the housing, the liquid cooling plate is located between the housing and the cell assembly, and two channels are formed inside the liquid cooling plate. One end of the two channels is connected, the other end of one channel corresponds to the first sub-cavity, and the other end of the other channel corresponds to the second sub-cavity. The liquid inlet and the liquid outlet are respectively formed at the ends of the two channels that are not connected.

[0009] The liquid cooling circuit includes two channels.

[0010] Optionally, thermally conductive adhesive is also provided between the liquid cooling plate and the battery cell assembly.

[0011] Optionally, an insulating plate is also provided between the thermally conductive adhesive and the battery cell assembly.

[0012] Optionally, a cooling water tank and a circulating water pump are also provided in the liquid cooling circuit;

[0013] The cooling water tank is used to contain coolant, and the cooling water tank has an inlet and an outlet, with the outlet connected to the liquid outlet.

[0014] The circulating water pump includes an inlet end and an outlet end, the inlet end being connected to the outlet end and the outlet end being connected to the inlet end.

[0015] Optionally, the air-cooling circuit includes an air-cooling channel, which includes a first channel and a second channel. The first channel is connected to the second channel, and the first channel is located within the second compartment. The second channel is located within the first compartment. The air inlet is formed on the first channel, and the air outlet is formed on the second channel; and / or,

[0016] A cooling fan is provided on the air-cooled circuit. The cooling fan is located inside the receiving cavity and on the partition. The air outlet of the cooling fan is oriented towards the second compartment.

[0017] Optionally, the battery module further includes:

[0018] A control module, disposed on the housing, is used to electrically connect the cooling fan and the battery cell assembly; and,

[0019] A temperature sensor, located inside the housing, is used to monitor the temperature of the battery cell assembly. The temperature sensor is electrically connected to the control module.

[0020] Optionally, the battery module further includes an auxiliary heat dissipation device, which includes multiple heat dissipation fins spaced apart outside the housing.

[0021] In addition, the present invention also proposes a temperature control method based on the above-mentioned battery module, wherein a cooling fan is provided on the air cooling circuit, the cooling fan is located in the receiving cavity and on the partition, and the air outlet of the cooling fan is arranged facing the second sub-cavity.

[0022] The temperature control method includes the following steps:

[0023] Obtain the actual temperature of the battery cell assembly;

[0024] Calculate the temperature difference between the actual temperature and the preset temperature;

[0025] The cooling fan control strategy is determined based on the temperature difference.

[0026] Optionally, the step of determining the cooling fan control strategy based on the temperature difference includes:

[0027] When the temperature difference is higher than the preset difference, the cooling fan is turned on;

[0028] When the temperature difference is lower than a preset difference, the cooling fan is turned off.

[0029] In this invention, the partition divides the receiving cavity into a first compartment and a second compartment. This is to allow for different cooling methods for the battery cells in the first and second compartments. During normal cooling, the cooling circulation system continuously absorbs heat, resulting in a large temperature difference between the front and rear compartments (i.e., better cooling at the front and worse cooling at the rear). To ensure the cooling efficiency of the battery module and reduce the temperature difference, the cooling circulation system uses both air-cooled and liquid-cooled circuits for simultaneous cooling. During cooling, the liquid inlet of the liquid-cooled circuit is located in the first compartment, and the outlet is located in the second compartment. The liquid cooling circuit has a cooling medium flowing from the first compartment to the second compartment to cool the battery cell assembly. The air inlet of the air cooling circuit is formed in the second compartment, and the air outlet is formed in the first compartment. The cooling medium in the air cooling circuit flows from the second compartment to the first compartment. The liquid cooling circuit and the air cooling circuit cool the battery module from two different compartments to avoid uneven cooling, reduce the temperature difference between the two ends of the battery module, keep the temperature difference of the battery module within a small range, ensure the consistency of the temperature fluctuation of each cell during the operation of the battery module, and improve the working efficiency of the battery module. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of an embodiment of the battery module provided by the present invention;

[0032] Figure 2 for Figure 1 A cross-sectional view;

[0033] Figure 3 for Figure 1 Schematic diagram of the central cooling circuit;

[0034] Figure 4 for Figure 1 A schematic diagram of the central pipeline.

[0035] Explanation of icon numbers:

[0036] label name label name 100 Battery Module 322 air vent 1 case 32a Liquid cooling plate 11 partition 321a aisle 12 First compartment 3211a First Pipeline 13 Second chamber 3212a Second Pipeline 2 Battery cell assembly 33 Cooling fan 3 Cooling circulation system 34 First Channel 31 Liquid cooling circuit 35 Second Channel 311 Inlet 4 thermal conductive adhesive 312 Liquid outlet 5 Insulating board 32 air-cooled circuit 6 Cooling water tank 321 air inlet 7 Circulating water pump

[0037] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0040] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0041] Temperature is a crucial factor affecting battery performance and lifespan. During charging and discharging, battery modules inevitably generate heat. Therefore, in the battery industry, liquid cooling plates are typically installed within the battery module to improve heat dissipation efficiency. A battery module usually contains multiple cell groups, each composed of multiple cells. Current technology primarily uses liquid cooling units to control the temperature of the cell groups. The typical supply water temperature of these liquid cooling units is 15-120℃, resulting in a low inlet temperature. During operation, the cells are generally set to 30℃ for intelligent temperature control. The problem is that the temperature difference between the coolant inlet and outlet of the cells leads to a greater temperature difference between the cells, affecting the consistency of cell performance and ultimately impacting cell lifespan.

[0042] In view of this, the present invention provides a battery module, Figures 1 to 4 This is an embodiment of the battery module provided by the present invention. The battery module will be described below with reference to the specific accompanying drawings.

[0043] Please see Figure 1 The battery module 100 includes a housing 1, a cell assembly 2, and a cooling circulation system 3. The housing 1 has a receiving cavity, and a partition 11 divides the receiving cavity into a first sub-cavity 12 and a second sub-cavity 13. The cell assembly 2 is disposed within the receiving cavity and includes multiple cells distributed in the first sub-cavity 12 and the second sub-cavity 13. The cooling circulation system 3 includes a liquid cooling circuit 31 and an air cooling circuit 32. The liquid cooling circuit 31 has an inlet 311 and an outlet 312, with the inlet 311 formed in the first sub-cavity 12 and the outlet 312 formed in the second sub-cavity 13. The air cooling circuit 32 has an air inlet 321 and an air outlet 322, with the air inlet 321 formed in the second sub-cavity 13 and the air outlet 322 formed in the first sub-cavity 12.

[0044] In the technical solution of this invention, the partition 11 divides the receiving cavity into a first sub-cavity 12 and a second sub-cavity 13. This is to allow for different cooling methods for the battery cells in the first sub-cavity 12 and the second sub-cavity 13. During normal cooling, the cooling circulation system 3 continuously absorbs heat, resulting in a large temperature difference between the front and rear sections (i.e., better cooling at the front and worse cooling at the rear). To ensure the cooling efficiency of the battery module 100 and reduce the temperature difference, the cooling circulation system 3 is equipped with a wind-cooled circuit 32 and a liquid-cooled circuit 31 for simultaneous cooling. During cooling, the inlet 311 of the liquid-cooled circuit 31 is formed in the first sub-cavity 12, and the outlet 312 is formed in the second sub-cavity 13. The cooling medium in circuit 31 flows from the first compartment 12 to the second compartment 13 to cool the battery cell assembly 2. The air inlet 321 of the air-cooled circuit 32 is formed in the second compartment 13, and the air outlet 322 is formed in the first compartment 12. The cooling medium in the air-cooled circuit 32 flows from the second compartment 13 to the first compartment 12. The liquid cooling circuit 31 and the air-cooled circuit 32 cool the battery module 100 from two different compartments to avoid uneven cooling, reduce the temperature difference between the two ends of the battery module 100, and keep the temperature difference of the battery module 100 within a small range. This ensures the consistency of the temperature fluctuation of each cell in the battery module 100 during operation and improves the working efficiency of the battery module 100.

[0045] It should be noted that during the cooling process, the cooling medium continuously absorbs the heat energy generated by the cooling medium, resulting in a continuous increase in its own temperature (i.e., cooling is achieved through heat exchange). This leads to a higher initial absorption of heat energy by the cooling medium. In subsequent cooling processes, as more and more heat energy is absorbed, the temperature of the cooling medium itself also increases, and the amount of heat energy that can be absorbed decreases. Therefore, uneven cooling may occur. This invention addresses this by placing the liquid cooling circuit 31 and the air cooling circuit 32 in two different compartments on the battery assembly. The cooling medium in the liquid cooling circuit 31 and the cooling medium in the air cooling circuit 32 flow in opposite directions. This ensures equal cooling on both sides and avoids uneven cooling.

[0046] Further, please refer to Figure 1 , Figure 2 and Figure 4A liquid cooling plate 32a is provided inside the housing 1. The liquid cooling plate 32a is located between the housing 1 and the battery cell assembly 2. Two channels 321a are formed inside the liquid cooling plate 32a. One end of the two channels 321a is connected. The other end of one channel 321a corresponds to the first sub-cavity 12, and the other end of the other channel 321a is connected to the second sub-cavity 13. The liquid inlet 311 and the liquid outlet 312 are respectively formed at the ends of the two channels 321a that are not connected. The liquid cooling circuit 31 includes the two channels 321a. In this embodiment, the battery module 100 further includes a liquid cooling plate 32a, which is disposed between the housing 1 and the cell assembly 2 for cooling the cell assembly 2. During the cooling process, the cooling medium flows from the inlet 311 into the channel 321a located in the first compartment 12 to cool the cell in the first compartment 12. Then, the cooling medium flows to the channel 321a located in the second compartment 13 to cool the cell in the second compartment 13, and then flows out from the outlet 312 to complete the cooling.

[0047] It should be noted that the specific shape of the channel 321a is not limited and can be set according to the specific type of the battery module 100. For example, please refer to [reference needed]. Figure 4 Each of the channels 321a includes a plurality of first pipes 3211a and a plurality of second pipes 3212a. The plurality of first pipes 3211a are spaced apart along a first direction. Each second pipe 3212a is arranged in an arc shape, and each second pipe 3212a is located between two first pipes 3211a to connect two adjacent first pipes 3211a to form a cooling circuit. The purpose of this arrangement is to increase the contact area between the liquid cooling system and the battery cell assembly 2 and improve the cooling efficiency.

[0048] Furthermore, referring to point 2, a thermally conductive adhesive 4 is also provided between the liquid cooling plate 32a and the battery cell assembly 2. The function of the thermally conductive adhesive 4 is to accelerate the transfer of heat energy, transferring as much of the heat energy generated by the battery cell assembly 2 as possible to the liquid cooling plate 32a, thereby improving cooling efficiency.

[0049] Furthermore, it should be noted that if the cooling medium within the liquid cooling plate 32a leaks and flows into the battery cell assembly 2, or if the battery cell assembly 2 experiences leakage due to special reasons and comes into contact with the cooling medium, it will damage the battery module 100. Therefore, to avoid the above situation, in this embodiment, refer to... Figure 2An insulating plate 5 is also provided between the thermally conductive adhesive 4 and the cell assembly 2. The insulating plate 5 is used to isolate the cell assembly 2 and the liquid cooling plate 32a, thereby improving the safety performance of the battery module 100.

[0050] In one embodiment, a cooling water tank 6 and a circulating water pump 7 are further provided on the liquid cooling circuit 31. The cooling water tank 6 is used to contain coolant, and an inlet and an outlet are formed on the cooling water tank 6, with the outlet connected to the liquid outlet 312. The circulating water pump 7 includes an inlet end and an outlet end, with the inlet end connected to the outlet and the outlet end connected to the inlet 311. Specifically, the cooling water tank 6 is used to recover the coolant that has absorbed heat. The coolant is cooled in the cooling water tank 6, and then the circulating water pump 7 draws out the cooled coolant and sends it into the cooling plate for continued cooling. This arrangement can achieve circulating cooling.

[0051] Please see Figure 3 and Figure 4 The air-cooled circuit 32 includes an air-cooled channel 321a, which includes a first channel 34 and a second channel 35. The first channel 34 is connected to the second channel 35, and the first channel 34 is located in the second sub-cavity 13, while the second channel 35 is located in the first sub-cavity 12. The air inlet 321 is formed on the first channel 34, and the air outlet 322 is formed on the second channel 35. In actual installation, when the battery cell assembly 2 is installed in the housing 1, there will be a gap between it and the housing 1 (i.e., the housing 1 is only used to fix and wrap the battery cell assembly 2 to protect it). Therefore, in this embodiment, the battery cell assembly 2 is separately installed in the first sub-cavity 12 and the second sub-cavity 13. The first channel 34 and the second channel 35 are the gaps between the battery cell assembly 2 and the first sub-cavity 12 and the second sub-cavity 13. With this setting, there is no need to add an additional air duct, and the air-cooling medium can directly contact the battery cell assembly 2, resulting in a better cooling effect.

[0052] Furthermore, in this embodiment, the partition 11 is disposed between the receiving cavities, dividing the housing 1 into an equal first cavity 12 and a second cavity 13, with the two ends of the first cavity 12 and the second cavity 13 connected. Simultaneously, a cooling fan 33 is provided on the air-cooling circuit 32, disposed within the receiving cavity and located on the partition 11, with the air outlet 322 of the cooling fan 33 facing the second cavity 13. In this way, the cooling fan 33 first blows the cooling medium into the first channel 34 (the gap between the battery cell and the second cavity 13) to cool the battery cell in the second area, and then flows into the second channel 35 (the gap between the battery cell and the first cavity 12) to cool the battery cell in the first area again.

[0053] It should be noted that the cooling starting area of ​​the liquid cooling circuit 31 is the first sub-cavity 12, and the cooling starting area of ​​the air cooling circuit 32 is the second sub-cavity 13. The two cooling circuits cool from different areas simultaneously to avoid uneven cooling.

[0054] Furthermore, the battery module 100 also includes a control module and a temperature sensor; the control module is disposed on the housing 1 and is used to electrically connect the cooling fan 33 and the cell assembly 2; the temperature sensor is disposed inside the housing 1 and is used to monitor the temperature of the cell assembly 2, and the temperature sensor is electrically connected to the control module. It should be noted that the amount of heat generated by the battery module 100 during operation varies at different times. Therefore, in order to reduce energy consumption, in this embodiment, the air-cooling circuit 32 will only operate when the temperature of the battery module 100 is too high. The temperature sensor is located inside the housing 1. When the temperature of the battery cell assembly 2 is too high, the temperature sensor will feed back the temperature value to the control module. The control module controls the air-cooling circuit 32 to operate based on the temperature feedback from the temperature sensor to assist in heat dissipation. When the temperature of the battery cell assembly 2 drops, the control module controls the air-cooling circuit 32 to stop operating. This setting can reduce energy consumption without affecting the cooling of the battery module 100.

[0055] Furthermore, in order to improve heat dissipation efficiency, the battery module 100 also includes an auxiliary heat dissipation device, which includes multiple heat dissipation fins spaced apart outside the housing 1.

[0056] In addition, the present invention also proposes a temperature control method for the battery module 100 based on the above-mentioned method, characterized in that a cooling fan 33 is provided on the air cooling circuit 32, the cooling fan 33 is provided in the receiving cavity and located on the partition 11, and the air outlet 322 of the cooling fan 33 is arranged facing the second sub-cavity 13.

[0057] Step S10: The temperature control method includes the following steps:

[0058] Step S20: Obtain the actual temperature of the battery cell assembly 2;

[0059] Step S30: Calculate the temperature difference between the actual temperature and the preset temperature;

[0060] Step S40: Determine the control strategy for the cooling fan 33 based on the temperature difference.

[0061] In this embodiment, when the battery module 100 is working, the temperature sensor obtains the temperature of the cell assembly 2, obtains the actual temperature, and transmits the actual temperature value to the control module. The control module compares the actual temperature with the preset temperature to obtain the temperature difference value, and then selects to turn the cooling fan 33 on or off according to the temperature difference value to provide auxiliary heat dissipation for the battery module 100.

[0062] Furthermore, step S40 also includes the following steps:

[0063] Step S401: When the temperature difference is higher than the preset difference, turn on the cooling fan 33;

[0064] Step S402: When the temperature difference is lower than the preset difference, turn off the cooling fan 33.

[0065] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A battery module, characterized in that, include: A housing having a receiving cavity formed therein, the receiving cavity being provided with a partition that divides the receiving cavity into a first sub-cavity and a second sub-cavity; A battery cell assembly, disposed within the receiving cavity, the battery cell assembly comprising a plurality of battery cells distributed in the first sub-cavity and the second sub-cavity; and A cooling circulation system includes a liquid cooling circuit and an air cooling circuit. The liquid cooling circuit is provided with a liquid inlet and a liquid outlet. The liquid inlet is formed in a first compartment and the liquid outlet is formed in a second compartment. The air cooling circuit is provided with an air inlet and an air outlet. The air inlet is formed in the second compartment and the air outlet is formed in the first compartment. A liquid cooling plate is provided inside the housing, and the liquid cooling plate is located between the housing and the battery cell assembly. Two channels are formed inside the liquid cooling plate, and one end of the two channels is connected. The other end of one channel corresponds to the first sub-cavity, and the other end of the other channel corresponds to the second sub-cavity. The liquid inlet and liquid outlet are respectively formed at the ends of the two channels that are not connected. The liquid cooling circuit includes two channels; Thermally conductive adhesive is also provided between the liquid cooling plate and the battery cell assembly; An insulating plate is also provided between the thermally conductive adhesive and the battery cell assembly; The air-cooling circuit includes an air-cooling channel, which comprises a first channel and a second channel. The first channel is connected to the second channel, and the first channel is located within the second compartment. The second channel is located within the first compartment. The air inlet is formed on the first channel, and the air outlet is formed on the second channel. A cooling fan is provided on the air-cooled circuit. The cooling fan is located inside the receiving cavity and on the partition. The air outlet of the cooling fan is oriented towards the second compartment.

2. The battery module as described in claim 1, characterized in that, A cooling water tank and a circulating water pump are also provided in the liquid cooling circuit; The cooling water tank is used to contain coolant, and the cooling water tank has an inlet and an outlet, with the outlet connected to the liquid outlet. The circulating water pump includes an inlet end and an outlet end, the inlet end being connected to the outlet end and the outlet end being connected to the inlet end.

3. The battery module as described in claim 1, characterized in that, The battery module also includes: A control module, disposed on the housing, is used to electrically connect the cooling fan and the battery cell assembly; and, A temperature sensor, located inside the housing, is used to monitor the temperature of the battery cell assembly. The temperature sensor is electrically connected to the control module.

4. The battery module as described in claim 1, characterized in that, The battery module also includes an auxiliary heat dissipation device, which includes multiple heat dissipation fins spaced apart outside the housing.

5. A temperature control method for a battery module based on any one of claims 1 to 4, characterized in that, A cooling fan is provided on the air-cooled circuit. The cooling fan is located inside the receiving cavity and on the partition. The air outlet of the cooling fan is oriented towards the second compartment. The temperature control method includes the following steps: Obtain the actual temperature of the battery cell assembly; Calculate the temperature difference between the actual temperature and the preset temperature; The cooling fan control strategy is determined based on the temperature difference.

6. The temperature control method as described in claim 5, characterized in that, The step of determining the cooling fan control strategy based on the temperature difference includes: When the temperature difference is higher than the preset difference, the cooling fan is turned on; When the temperature difference is lower than a preset difference, the cooling fan is turned off.

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