Battery module and battery pack

Abstract

The present application provides a battery module and a battery pack. The battery module comprises: a case provided with an accommodating space as well as a pressure relief opening and a first air inlet which are separately communicated with the accommodating space, wherein a pressure relief mechanism is arranged at the pressure relief opening, and an air inlet mechanism is arranged at the first air inlet; cells arranged in the accommodating space; and a first detection unit mounted on the case and used for implementing detection on a preset object, wherein the first detection unit is electrically connected to the pressure relief mechanism, the pressure relief mechanism opens the pressure relief opening when the first detection unit detects thermal runaway of the cells, and the air inlet mechanism opens the first air inlet when the pressure in the accommodating space is smaller than or equal to a pressure threshold.

Description

Battery module and battery pack

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 22, 2023, with application number 2023235277508. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present application relate to the field of battery technology, and in particular to a battery module and a battery pack. Background Art

[0003] New energy technologies are developing faster and faster. Battery modules have been widely used in various new energy vehicles and energy storage power stations. During the use of battery modules, if short circuits, overcharges, and other phenomena occur, a large amount of heat will accumulate inside the battery modules, resulting in thermal runaway. Thermal runaway will cause the internal pressure of the battery modules to be too high, causing fire or even explosion.

[0004] In the related art, a pressure relief valve is generally provided on the battery module. When the internal pressure of the battery module is too high, the pressure relief valve is flushed open to release the internal pressure of the battery module. This passive exhaust method is prone to the situation where the pressure relief valve cannot be flushed open, resulting in failure to release the internal pressure of the battery module. Technical issues

[0005] The present application provides a battery module and battery pack that can achieve active exhaust to avoid the situation where even if thermal runaway occurs in the battery cell, the internal pressure of the shell does not open the pressure relief valve. Technical Solutions

[0006] In the first aspect, an embodiment of the present application provides a battery module, comprising: a shell, forming a accommodating space and a pressure relief port and a first air inlet respectively connected to the accommodating space, the pressure relief port is provided with a pressure relief mechanism, and the first air inlet is provided with an air intake mechanism; a battery cell, arranged in the accommodating space; a first detection unit, mounted on the shell and used to detect a preset object, the first detection unit being electrically connected to the pressure relief mechanism, when the first detection unit detects thermal runaway of the battery cell, the pressure relief mechanism opens the pressure relief port, and when the pressure in the accommodating space is less than or equal to a pressure threshold, the air intake mechanism opens the first air inlet.

[0007] In a second aspect, an embodiment of the present application provides a battery pack, which includes a battery management unit and the battery module, and the battery management unit is electrically connected to the pressure relief mechanism, the battery cell and the first detection unit respectively. Beneficial effects

[0008] The beneficial effects of the present application are as follows: different from the related art, the battery module provided by the embodiment of the present application includes: a shell, which is formed with a storage space and a pressure relief port and a first air inlet respectively connected to the storage space, the pressure relief port is provided with a pressure relief mechanism, and the first air inlet is provided with an air intake mechanism; a battery cell is arranged in the storage space; a first detection unit is installed on the shell and is used to detect a preset object, the first detection unit is electrically connected to the pressure relief mechanism, and when the first detection unit detects that the battery cell is in thermal runaway, the pressure relief mechanism opens the pressure relief port, and the pressure in the storage space is less than or equal to the pressure threshold, the air intake mechanism opens the first air inlet. On the one hand, the preset object is actively detected by the first detection unit, so that active exhaust is achieved when thermal runaway occurs in the battery cell. Compared with the passive exhaust method in the related art, it avoids the situation that even if thermal runaway occurs in the battery cell, the internal pressure of the shell does not rush open the pressure relief valve, thereby avoiding the risk of failure to release the internal pressure of the shell. On the other hand, when the pressure in the accommodation space is less than or equal to the pressure threshold, the air intake mechanism opens the first air inlet, allowing external air to enter the accommodation space, further alleviating thermal runaway of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0010] FIG1 is a schematic diagram of the three-dimensional structure of an embodiment of a battery module provided by the present application;

[0011] FIG2 is a schematic diagram of the exploded structure of the battery module in FIG1 ;

[0012] FIG3 is a schematic cross-sectional view of the housing and the pressure relief valve in FIG1 taken along the line F1 - F1 upwards;

[0013] FIG4 is a schematic cross-sectional view of the housing in FIG3 ;

[0014] FIG5 is a schematic diagram of the three-dimensional structure of another embodiment of the battery module provided by the present application;

[0015] FIG6 is a schematic cross-sectional view of the battery module in FIG5 ;

[0016] FIG7 is a schematic diagram of the three-dimensional structure of a battery pack embodiment provided in the present application;

[0017] FIG8 is a schematic block diagram of the control of the battery pack in FIG7 ;

[0018] FIG9 is a schematic cross-sectional view of the battery pack in FIG7 , viewed from the top. Modes for Carrying Out the Invention

[0019] Please refer to Figures 1 and 2 together. Figure 1 is a schematic diagram of the three-dimensional structure of an embodiment of the battery module 10 provided in this application, and Figure 2 is a schematic diagram of the decomposed structure of the battery module 10 in Figure 1. The battery module 10 in this embodiment includes a shell 11, a battery cell 12 and a first detection unit 13.

[0020] Please refer to Figures 3 and 4 together. Figure 3 is a schematic cross-sectional view of the shell 11 and the pressure relief mechanism 11a in Figure 1 taken along the F1-F1 upward direction. Figure 4 is a schematic cross-sectional view of the shell 11 in Figure 3. The shell 11 is formed with a receiving space 101, a pressure relief port 102 and a first air inlet 103. The pressure relief port 102 and the first air inlet 103 are respectively connected to the receiving space 101. The battery cell 12 is disposed in the receiving space 101. In actual applications, the number of battery cells 12 can be multiple, and the multiple battery cells 12 are arranged in the receiving space 101 in a converging manner.

[0021] The pressure relief port 102 is provided with a pressure relief mechanism 11 a , and the first air inlet 103 is provided with an air inlet mechanism 11 b .

[0022] Further referring to Figures 2, 3 and 4, the first detection unit 13 is installed on the shell 11 and is used to detect a preset object. The first detection unit 13 is electrically connected to the pressure relief mechanism 11a. When the first detection unit 13 detects that the battery cell 12 is in thermal runaway, the pressure relief mechanism 11a opens the pressure relief port 102, thereby releasing the internal pressure of the shell 11, avoiding the internal pressure of the shell 11 being too high to cause fire or even explosion. In this embodiment, the first detection unit 13 actively detects the preset object, thereby achieving active exhaust when the battery cell has thermal runaway. Compared with the passive exhaust method in the related art, it avoids the situation that even if the battery cell 12 has thermal runaway, the internal pressure of the shell 11 does not open the pressure relief valve, thereby avoiding the risk of failure to release the internal pressure of the shell 11.

[0023] Furthermore, when the pressure in the accommodating space 101 is less than or equal to the pressure threshold, the air intake mechanism 11b opens the first air inlet 103, thereby allowing external air to enter the accommodating space 101, further alleviating the thermal runaway of the battery cell 12. It can be understood that the specific value of the pressure threshold can be set according to actual needs and is not limited to this.

[0024] Optionally, in actual applications, the pressure relief mechanism 11a can use a solenoid valve. When it is determined that the battery cell 12 has thermal runaway, the solenoid valve is controlled to open the pressure relief port 102. The air intake mechanism 11b can use a pressure valve or a solenoid valve. For example, when a pressure valve is used, when the pressure in the accommodation space 101 is less than or equal to the pressure threshold, the external pressure of the shell 11 is greater than the internal pressure of the shell 11. At this time, the external air automatically breaks open the pressure valve and enters the accommodation space 101.

[0025] Optionally, the pressure relief port 102 and the first air inlet 103 are respectively arranged on opposite sides of the shell 11, so that the airflow direction of the above-mentioned exhaust process and the airflow direction of the air intake process are in the same direction, thereby improving the airflow stability during the exhaust process and the air intake process.

[0026] In a specific application scenario, the first detection unit 13 includes a temperature detector 131, which is used to detect the temperature of the battery cell 12. When the temperature of the battery cell 12 is greater than or equal to the temperature threshold, the pressure relief mechanism 11a opens the pressure relief port 102. That is, in this specific application scenario, the above-mentioned preset object is the battery cell 12, and the detection result of the first detection unit 13 is the temperature of the battery cell 12. In this way, the heat accumulation caused by thermal runaway of the battery cell 12 is avoided, which may cause the internal pressure of the shell 11 to be too high, and even cause fire or explosion.

[0027] It can be understood that in actual applications, the installation position of the temperature detector 131 can be set according to actual needs, and the temperature threshold can also be set according to actual needs. There is no limitation on this. For example, the temperature detector 131 can be set on the shell 11, and the temperature threshold can be set to be greater than or equal to 75°C.

[0028] In another specific application scenario, the first detection unit 13 includes a gas detector 132, which is used to detect the gas composition in the accommodating space 101. When the gas composition in the accommodating space 101 contains thermal runaway gas, the pressure relief mechanism 11a opens the pressure relief port 102. That is, in this other specific application scenario, the above-mentioned preset object is the gas in the accommodating space 101, and the detection result of the first detection unit 13 is the gas composition in the accommodating space 101. In this way, the toxic gas generated by thermal runaway of the battery cell 12 can be avoided from causing poisoning to people, or even fire or explosion.

[0029] It can be understood that in actual applications, the installation position of the gas detector 132 can be set according to actual needs, and the gas components detected in the accommodating space 101 can also be set according to actual needs. There is no limitation on this. For example, the gas detector 132 can be set on the shell 11, and the gas components detected in the accommodating space 101 can be at least one of hydrogen, carbon monoxide, methane and other gases.

[0030] Among them, in this embodiment, the first detection unit 13 performs detection through the above-mentioned temperature detector 131 and gas detector 132 respectively, and when the temperature of the battery cell 12 is greater than or equal to the temperature threshold and the gas composition in the accommodating space 101 contains thermal runaway gas, it is determined that the battery cell 12 has thermal runaway, so that the pressure relief mechanism 11a opens the pressure relief port 102, thereby improving the accuracy of thermal runaway detection of the battery cell 12.

[0031] Optionally, the battery module 10 in this embodiment further includes a second detection unit (not shown in the figure), which is used to detect the pressure in the accommodating space 101. For example, the above-mentioned air intake mechanism 11b uses an electromagnetic valve. When the second detection unit detects that the pressure in the accommodating space 101 is less than or equal to the pressure threshold, the electromagnetic valve is controlled to open the first air inlet 103, thereby realizing active detection of the pressure in the accommodating space 101.

[0032] It is understandable that in actual applications, the position of the second detection unit can be set according to actual needs, for example, the second detection unit is set on the housing 11.

[0033] Please refer to Figure 5, which is a schematic diagram of the three-dimensional structure of another embodiment of the battery module 20 provided in the present application. Figure 6 is a schematic diagram of the cross-section of the battery module 20 in Figure 5 taken along F2-F2 upward. The battery module 20 in this embodiment also includes an exhaust unit 21. The other structures of the battery module 20 in this embodiment are the same as those of the battery module 10 in the above embodiment and will not be repeated here.

[0034] The exhaust unit 21 is included, and the exhaust unit 21 is used to communicate with the pressure relief port 102 when the pressure relief mechanism 11a opens the pressure relief port 102, thereby exhausting the gas in the accommodating space 101 and improving the exhaust efficiency of the gas in the accommodating space 101.

[0035] Furthermore, the exhaust unit 21 includes an exhaust part 211 and an exhaust mechanism 212. The exhaust part 211 is provided with an exhaust channel 201 and a second air inlet 202 and an air outlet 203 respectively connected to the exhaust channel 201. When the pressure relief mechanism 11a opens the pressure relief port 102, the second air inlet 202 is connected to the pressure relief port 102, and the exhaust mechanism 212 is arranged at the air outlet 203, so that the gas in the accommodating space 101 is discharged into the exhaust channel 201 through the pressure relief port 102 and the second air inlet 202 in turn, and then discharged from the air outlet 203 by the exhaust mechanism 212.

[0036] In practical applications, the exhaust mechanism 212 may be a fan.

[0037] Please refer to Figures 7, 8 and 9 together. Figure 7 is a three-dimensional structural schematic diagram of the battery pack 30 embodiment provided in the present application, Figure 8 is a control schematic block diagram of the battery pack 30 in Figure 7, and Figure 9 is a cross-sectional schematic diagram of the battery pack 30 in Figure 7 taken from F3-F3 upward. The battery pack 30 in this embodiment includes a battery management unit 31 and a battery module in any of the above embodiments. In this embodiment, the above-mentioned battery module 20 is taken as an example.

[0038] Among them, the battery management unit 31 is electrically connected to the pressure relief mechanism 11a, the battery cell 12 and the first detection unit 13 respectively, so that the battery management unit 31 determines whether the battery cell 12 has thermal runaway according to the detection result of the first detection unit 13. If thermal runaway occurs, the pressure relief mechanism 11a is controlled to open the pressure relief port 103.

[0039] It can be understood that in this embodiment, the battery management unit 31 is electrically connected to the temperature detector 131 and the gas detector 132 of the first detection unit 13 respectively.

[0040] Furthermore, in this embodiment, there are multiple battery modules 10, and the battery management unit 31 is electrically connected to the pressure relief mechanism 11a, the battery cell 12 and the first detection unit 13 of each battery module 10, respectively, so that the first detection unit 13 of each battery module 10 can be detected separately, so that if a battery cell 12 in multiple battery modules 10 has thermal runaway, each battery module 10 can perform exhaust and air intake processes separately, so as to avoid the thermal runaway spread caused by the battery cell 12 with thermal runaway, thereby affecting the battery cell that has not experienced thermal runaway.

[0041] In this embodiment, the number of second air inlets 202 formed by the exhaust part 211 of the exhaust unit 21 is multiple, and the multiple second air inlets 202 are respectively connected to the exhaust channel 201, so that the gas in the accommodating space 101 of the multiple battery modules 10 is discharged into the exhaust channel 201 through the multiple second air inlets 202, and finally discharged from the air outlet 203.

[0042] Furthermore, the battery pack 30 in this embodiment also includes a battery rack 32, the battery rack 32 is provided with a battery compartment 301, the shell 11 is arranged in the battery compartment 301, that is, the battery module 10 is arranged in the battery compartment 301. In this embodiment, there are multiple battery compartments 301, and each battery compartment 301 accommodates a battery module 10.

[0043] Furthermore, the battery pack 30 in this embodiment also includes an alarm 23, and the battery management unit 31 is electrically connected to the alarm 23, so that when the battery management unit 31 determines that the battery cell 12 has thermal runaway, it controls the alarm 23 to sound an alarm to alert the staff.

[0044] Different from the related art, the battery module provided in the embodiment of the present application includes: a shell, which is formed with a accommodating space and a pressure relief port and a first air inlet respectively connected to the accommodating space, the pressure relief port is provided with a pressure relief mechanism, and the first air inlet is provided with an air intake mechanism; a battery cell is arranged in the accommodating space; a first detection unit is installed on the shell and is used to detect a preset object, the first detection unit is electrically connected to the pressure relief mechanism, and when the first detection unit detects thermal runaway of the battery cell, the pressure relief mechanism opens the pressure relief port, and the pressure in the accommodating space is less than or equal to the pressure When the threshold is strong, the air intake mechanism opens the first air intake port. On the one hand, the preset object is actively detected by the first detection unit, so that active exhaust is achieved when thermal runaway occurs in the battery cell. Compared with the passive exhaust method in the related art, it avoids the situation that even if thermal runaway occurs in the battery cell, the internal pressure of the shell does not open the pressure relief valve, thereby avoiding the risk of failure to release the internal pressure of the shell. On the other hand, when the pressure in the accommodation space is less than or equal to the pressure threshold, the air intake mechanism opens the first air intake port, allowing external air to enter the accommodation space, further alleviating the thermal runaway of the battery cell.

Claims

1. A battery module, comprising: A shell is formed with a containing space and a pressure relief port and a first air inlet respectively connected to the containing space, the pressure relief port is provided with a pressure relief mechanism, and the first air inlet is provided with an air inlet mechanism; A battery cell is arranged in the accommodation space; A first detection unit is installed on the shell and is used to detect a preset object. The first detection unit is electrically connected to the pressure relief mechanism. When the first detection unit detects thermal runaway of the battery cell, the pressure relief mechanism opens the pressure relief port. When the pressure in the accommodating space is less than or equal to a pressure threshold, the air intake mechanism opens the first air intake port.

2. The battery module according to claim 1, wherein: The first detection unit includes a temperature detector, the preset object is the battery cell, the temperature detector is used to detect the temperature of the battery cell, and when the temperature of the battery cell is greater than or equal to a temperature threshold, the pressure relief mechanism opens the pressure relief port.

3. The battery module according to claim 1 or 2, wherein: The first detection unit includes a gas detector, the preset object is the gas in the accommodating space, the gas detector is used to detect the gas composition in the accommodating space, and when the gas composition in the accommodating space contains thermal runaway gas, the pressure relief mechanism opens the pressure relief port.

4. The battery module according to claim 1, wherein: The battery module further includes an exhaust unit, which is used to communicate with the pressure relief port when the pressure relief mechanism opens the pressure relief port, so as to exhaust the gas in the accommodation space.

5. The battery module according to claim 4, wherein: The exhaust unit includes an exhaust component and an exhaust mechanism. The exhaust component is provided with an exhaust channel and a second air inlet and an air outlet respectively connected to the exhaust channel. When the pressure relief mechanism opens the pressure relief port, the second air inlet is connected to the pressure relief port. The exhaust mechanism is arranged at the air outlet.

6. The battery module according to claim 1, wherein: The battery module further includes a second detection unit, and the second detection unit is used to detect the pressure in the accommodation space.

7. The battery module according to claim 1, wherein: The pressure relief port and the first air inlet are respectively arranged on two opposite sides of the shell.

8. A battery pack, comprising a battery management unit and the battery module according to any one of claims 1 to 7, wherein the battery management unit is electrically connected to the pressure relief mechanism, the battery cell and the first detection unit respectively.

9. The battery pack according to claim 8, wherein: The battery pack also includes a battery rack, the battery rack is provided with a battery compartment, and the shell is arranged in the battery compartment.

10. The battery pack according to claim 8, wherein: The battery pack further includes an alarm, and the battery management unit is electrically connected to the alarm.

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