Battery pack

Abstract

The utility model discloses a battery pack. The battery pack comprises a box body bottom plate; a discharge port; the battery cell tray is used for bearing a battery cell and is placed on the box body bottom plate, a gap is formed between the battery cell tray and the box body bottom plate in the height direction, an air inlet hole is formed in the face, connected with the battery cell, of the battery cell tray, the air inlet hole is communicated with the battery cell and the gap, a confluence groove is formed in a notch in one side of the battery cell tray, and the confluence groove protrudes towards the battery cell; the confluence groove is respectively communicated with the gap and the discharge port; and gas released from the battery cell enters the gap through the gas inlet hole and is discharged from the discharge port through the confluence groove. According to the battery pack provided by the utility model, the confluence chamber is formed between the confluence groove and the bottom plate of the box body along the height direction, and the confluence chamber can collect gas from a plurality of battery cells and then exhaust the gas through the exhaust port, so that the exhaust efficiency is improved. And meanwhile, when the battery cells are abnormal, the confluence cavity is used as a buffer area, so that the impact of direct pressure on the battery shell can be reduced, and the safety of the battery pack is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field, especially a kind of battery pack. BACKGROUND

[0002] With the rapid development of electric vehicle industry, large cylindrical battery cell gradually becomes the mainstream choice in the field of power battery due to its high energy density and good thermal management performance. Under this background, the glue filling cylindrical CTP (Cell to Pack) technology is widely used because it can effectively fix the battery cell, improve the space utilization and the overall performance of the battery system. However, the application of this technology also brings some challenges, especially the exhaust problem of cylindrical battery cell.

[0003] At present, during the implementation of the glue filling cylindrical CTP technology, the internal space of the module is blocked in a large area due to the glue filling operation, which limits the normal exhaust of the gas generated by the battery cell during charging and discharging. If appropriate measures are not taken, this poor exhaust condition can easily cause a sharp thermal runaway phenomenon, which affects the safety of the entire battery pack and poses a serious threat to the operation safety of electric vehicles.

[0004] The utility model patent with application number 202321918059.X discloses a battery pack, which includes battery cells, a support and a box. Each battery cell has a battery cell explosion-proof valve. The support has an exhaust passage. The box has a mounting compartment and an exhaust compartment. The battery cells are installed in the mounting compartment through the support. The exhaust passage corresponds to the battery cell explosion-proof valve and is in communication with the exhaust compartment to introduce the gas into the exhaust compartment when the battery cell explosion-proof valve exhausts.

[0005] Although the above-mentioned patent can timely exhaust the gas in the box of the battery pack and solve the problem of poor safety performance of the battery pack, the space of the exhaust passage is limited, which can easily cause blockage and affect the exhaust effect. If the battery cell is overcharged or has an internal short circuit, a large amount of gas will be generated, and the limited exhaust passage will result in low exhaust efficiency. UTILITY MODEL CONTENTS

[0006] The embodiment of the utility model discloses a battery pack, which includes a box bottom plate, an exhaust port, a battery cell tray for carrying battery cells, the battery cell tray is placed on the box bottom plate and has a gap in the height direction with the box bottom plate, the battery cell tray is provided with an air inlet hole on the side in contact with the battery cell, the air inlet hole is in communication with the battery cell and the gap respectively, a converging groove is arranged at the notch of one side of the battery cell tray, the converging groove is protruded towards the battery cell, and the converging groove is in communication with the gap and the exhaust port respectively; the gas released from the battery cell enters the gap through the air inlet hole and is exhausted from the exhaust port through the converging groove.

[0007] According to the technical scheme, each battery cell has a corresponding air inlet hole, and the gas released by each battery cell can directly pass through the air inlet hole and be discharged through the air inlet hole. The gap between the battery cell tray and the bottom plate of the box body is communicated with the air inlet hole, which helps to uniformly release the internal pressure. The flow groove and the bottom plate of the box body form a flow chamber in the height direction, which can collect the gas from the plurality of battery cells and then discharge the gas through the discharge port, which improves the gas discharge efficiency. At the same time, when the battery cell is abnormal, the flow chamber as a buffer zone can reduce the impact of direct pressure on the battery shell, and improve the safety of the battery pack. The utility model discloses a structure of the communicated air inlet hole, gap and flow chamber, which can effectively discharge the gas of the battery pack and improve the safety and reliability of the battery pack.

[0008] According to another specific embodiment of the utility model, the battery pack includes a box body exhaust passage arranged on one side of the battery pack along a first direction, the first direction being perpendicular to the height direction, and the box body exhaust passage being provided with a discharge port; the flow groove is in butt joint communication with the box body exhaust passage.

[0009] According to another specific embodiment of the utility model, the flow groove is provided with a first air vent on a side surface thereof; the box body exhaust passage is provided with a second air vent on a side surface thereof, and the second air vent is in butt joint communication with the first air vent in a sealed connection mode.

[0010] According to another specific embodiment of the utility model, the flow groove and the box body exhaust passage form an exhaust chamber in butt joint, the top plate of the flow groove is overlapped with the top plate of the box body exhaust passage; the top plate of the flow groove is provided with a step portion, the top plate of the box body exhaust passage is provided with an overlapping portion, and the step portion is embedded with the overlapping portion in a sealed connection mode to block the overflow of the gas from the top of the exhaust chamber.

[0011] According to another specific embodiment of the utility model, a groove is arranged on the tread of the step portion, and the groove is used for filling a sealing material to realize the sealed connection between the step portion and the overlapping portion.

[0012] According to another specific embodiment of the utility model, the battery pack includes a buffer chamber arranged on one side of the battery pack along the first direction.

[0013] According to another specific embodiment of the utility model, a separation partition plate is arranged in the buffer chamber along the height direction, the buffer chamber is divided into a plurality of sub-chambers, and one of the sub-chambers is the box body exhaust passage.

[0014] According to another specific embodiment of the utility model, the battery cell tray is provided with a flange extending in the circumferential direction thereof, the flange protrudes from the tray towards the bottom plate of the box body, and the flange is placed on the bottom plate of the box body to form a gap between the battery cell tray and the bottom plate of the box body in the height direction.

[0015] According to another specific embodiment of the present application, the battery pack comprises a battery management system, the battery management system is connected with the pressure sensor, and the battery management system is used for comparing the air pressure value with a preset air pressure value, outputting a predetermined warning signal if the air pressure value exceeds the preset air pressure value; and / or mica paper is arranged between the battery cell and the battery cell tray along the height direction, and the mica paper is sealingly connected with the battery cell tray.

[0016] According to another specific embodiment of the present application, the battery pack comprises a battery management system, the battery management system is connected with the pressure sensor, and the battery management system is used for comparing the air pressure value with a preset air pressure value, outputting a predetermined warning signal if the air pressure value exceeds the preset air pressure value; and / or mica paper is arranged between the battery cell and the battery cell tray along the height direction, and the mica paper is sealingly connected with the battery cell tray. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 FIG. 4 shows a cross-sectional view of the battery pack in the embodiment of the present application;

[0018] Figure 2 FIG. 5 shows a cross-sectional view of the battery cell in the embodiment of the present application; Figure 1 FIG. 6 shows an enlarged view of the area A in FIG. 5;

[0019] Figure 3 FIG. 7 shows an exploded view of the battery cell, the mica paper and the battery cell tray in the embodiment of the present application;

[0020] Figure 4 FIG. 8 shows a bottom perspective view of the battery cell tray in the embodiment of the present application;

[0021] Figure 5 FIG. 9 shows a cross-sectional view of the battery cell in the embodiment of the present application. DETAILED DESCRIPTION

[0022] The present application will be described in detail below with specific embodiments, and those skilled in the art can easily understand other advantages and effects of the present application from the disclosure. Although the description of the present application will be introduced in combination with the preferred embodiments, this does not mean that the features of the present application are limited to the embodiments. On the contrary, the purpose of introducing the present application in combination with the embodiments is to cover other options or modifications that can be extended based on the claims of the present application. In order to provide a deep understanding of the present application, many specific details will be included in the following description. The present application can also be implemented without using these details. In addition, in order to avoid confusion or obscure the focus of the present application, some specific details will be omitted in the description. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0023] It should be noted that in the present specification, similar reference numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings.

[0024] The terms "first", "second", and the like are merely used to distinguish descriptions, and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present embodiment, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set", "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present embodiment can be understood according to the specific circumstances.

[0026] In order to make the purpose, technical scheme and advantages of the utility model more clear, the embodiments of the utility model will be further described in detail below with reference to the drawings.

[0027] Reference Figure 1 , Figure 3 and Figure 4 , the utility model provides a kind of battery pack 0, including box bottom plate 11, discharge port 121 and electric core tray 2. Among them, electric core tray 2 is used to carry electric core 3, electric core tray 2 is placed on box bottom plate 11, with gap 4 in height direction, i.e. Z direction with box bottom plate 11.Electric core tray 2 is equipped with gas inlet hole 21 on the side of electric core 3, and gas inlet hole 21 is communicated with electric core 3 and gap 4 respectively.Electric core tray 2 is equipped with the gap 22 of one side, and the gap 22 is equipped with the flow groove 23, and the flow groove 23 is protruded towards electric core 3, and the flow groove 23 is communicated with gap 4 and discharge port 121 respectively.Gas released from electric core 3 enters gap 4 through gas inlet hole 21, and is discharged from discharge port 121 through flow groove 23.

[0028] In the present embodiment, when electric core 3 is thermal runaway, thermal runaway gas enters gap 4 through gas inlet hole 21, and is gathered in the flow chamber 232 formed by flow groove 23 after large-area heat dissipation, and is finally discharged from discharge port 121 through box exhaust passage 12.This process avoids gas leakage in battery pack 0, greatly improves the safety of battery pack 0.

[0029] Reference Figure 3 and Figure 4 , in the present embodiment, one flow groove 23 is shared by every 3 columns of electric cores 3, which effectively avoids the situation that when one electric core 3 is out of control, gap 4 (such as Figure 1The heat is not discharged in time due to the too small size, triggering thermal runaway of other normal battery cells 3.

[0030] According to the technical scheme, each battery cell 3 has a corresponding air inlet hole 21, and the gas released by each battery cell 3 can directly pass through the air inlet hole 21 and be discharged through the air inlet hole 21. The gap 4 between the battery cell tray 2 and the box bottom plate 11 is communicated with the air inlet hole 21, which is helpful to uniformly release the internal pressure. The flow collection groove 23 and the box bottom plate 11 form a flow collection chamber 232 in the height direction, i.e., the Z direction, which can collect the gas from the plurality of battery cells 3 and then discharge the gas through the discharge port 121, which improves the gas discharge efficiency. Meanwhile, when the battery cell 3 is abnormal, the flow collection chamber 232 as a buffer zone can reduce the impact of direct pressure on the battery shell and prevent the gas from being discharged in an instant, which can cause a sharp thermal runaway phenomenon, thereby improving the safety of the battery pack 0. The utility model designs the structure of the communicated air inlet hole 21, gap 4 and flow collection chamber 232, so that the battery pack 0 can more effectively discharge the gas and improve the safety and reliability of the battery pack 0.

[0031] Reference Figure 1 In some possible embodiments of the utility model, the battery pack 0 comprises a box exhaust passage 12 arranged on one side of the battery pack 0 in the first direction, i.e., the Y direction, and the first direction, i.e., the Y direction, is perpendicular to the height direction, i.e., the Z direction. The box exhaust passage 12 is provided with a discharge port 121. The flow collection groove 23 is connected to the box exhaust passage 12.

[0032] Exemplarily, the first direction, i.e., the Y direction, is the length direction of the battery pack 0. The second direction, i.e., the X direction, is the width direction of the battery pack 0. The second direction, i.e., the X direction, is perpendicular to the first direction, i.e., the Y direction, and the height direction, i.e., the Z direction. Figure 3 And Figure 4 The arrangement direction of the battery cells 3 shown in the figure is the width direction.

[0033] In the embodiment, the flow collection groove 23 is connected to the box exhaust passage 12, and the gas released by the battery cell 3 is discharged out of the box 1 of the battery pack 0 through the discharge port 121 of the box exhaust passage 12.

[0034] Reference Figure 1 In some possible embodiments, the box exhaust passage 12 is further provided with a box explosion-proof valve 10 on the outer wall of the box exhaust passage 12. When the battery cell 3 in the box 1 of the battery pack 0 releases gas due to thermal runaway, the gas enters the box exhaust passage 12 through the air inlet hole 21, the gap 4 and the flow collection chamber 232 formed by the flow collection groove 23. When the gas pressure in the box exhaust passage 12 is too large, the box explosion-proof valve 10 is broken, and the box explosion-proof valve 10 releases the pressure of the battery pack 0, which improves the safety of the battery pack 0.

[0035] Reference Figure 1 and Figure 2 In some possible embodiments of the utility model, the first air vent 231 is arranged on the side surface of the busbar groove 23. The second air vent 122 is arranged on the side surface of the box exhaust channel 12, and the second air vent 122 is in sealed connection with the first air vent 231.

[0036] Exemplarily, the first air vent 231 is arranged on one side surface 23A of the busbar groove 23, and the first air vent 231 serves as the gas outlet of the busbar groove 23. Figure 2 Exemplarily, the second air vent 122 is arranged on one side surface 12A of the box exhaust channel 12, and the second air vent 122 serves as the gas inlet of the box exhaust channel 12. Figure 2

[0037] In some possible embodiments, the first air vent 231 and the second air vent 122 are of the same size, so that the gas can enter the box exhaust channel 12 from the busbar chamber 232.

[0038] In the embodiment, the first air vent 231 is in sealed connection with the second air vent 122, so that the air in the busbar groove 23 flows into the box exhaust channel 12. Figure 1 and Figure 2 The first air vent 231 and the second air vent 122 are in sealed connection, so that the gas is prevented from being released from the gap between the first air vent 231 and the second air vent 122 into other parts of the electric box 1 except the reserved gas flow channel, thereby avoiding the safety hazard of the battery pack 0. The reserved gas flow channel includes the gas inlet hole 21, the gap 4, the busbar groove 23, the box exhaust channel 12, and the exhaust port 121.

[0039] In other possible embodiments, the first air vent 231 and the second air vent 122 can be partially connected, so that the gas can enter the box exhaust channel 12 from the busbar chamber 232. Exemplarily, the size of the first air vent 231 is greater than that of the second air vent 122; or the size of the first air vent 231 is less than that of the second air vent 122.

[0040] Reference Figure 1 , Figure 2 and in combination with Figure 3 In some possible embodiments of the utility model, the busbar groove 23 and the box exhaust channel 12 are connected to form the exhaust chamber 5. The top plate 233 of the busbar groove 23 is overlapped with the top plate 123 of the box exhaust channel 12. The top plate 233 of the busbar groove 23 is provided with a stepped portion 2331. The top plate 123 of the box exhaust channel 12 is provided with an overlapping portion 1231. The stepped portion 2331 and the overlapping portion 1231 are embedded and in sealed connection, so as to block the gas from overflowing from the top of the exhaust chamber 5. ​

[0041] In the embodiment, the confluence groove 23 and the bottom plate 11 of the box form a confluence chamber 232. The confluence chamber 232 and the box exhaust passage 12 jointly form the exhaust chamber 5. The stepped portion 2331 of the confluence groove 23 and the lapping portion 1231 of the box exhaust passage 12 are sealingly connected, which blocks the gas from being released from unintended places, especially into the inside of the box 1, thereby causing the safety problem of the battery pack 0. Here, the unintended places refer to other parts than the reserved gas flow passages, which include the gas inlet hole 21, the gap 4, the confluence groove 23, the box exhaust passage 12, and the exhaust port 121.

[0042] That is to say, when the battery cell 3 is normally working, the bottom of the mica paper 9 at the bottom of the battery cell 3 (in fact, the mica paper 9 is not impacted and is not damaged when the battery cell 3 is normally working), the gas inlet hole 21, the gap 4, and the exhaust chamber 5 (the confluence chamber 232 and the box exhaust passage 12) form a closed chamber. When the battery cell 3 is in thermal runaway, the gas has only one discharge path, that is, the battery cell explosion-proof valve 32, the damaged mica paper 9, the gas inlet hole 21, the gap 4, the exhaust chamber 5 (the confluence chamber 232 and the box exhaust passage 12), and the exhaust port 121, and there is no other gas flow path.

[0043] Reference Figure 2 And Figure 3 In some possible embodiments provided by the utility model, the tread surface 2332 of the stepped portion 2331 is provided with a groove 2333 for filling a sealing material, so that the stepped portion 2331 is sealingly connected with the lapping portion 1231.

[0044] Exemplarily, the sealing material is, for example, glue or foaming glue.

[0045] In the embodiment, the groove 2333 is arranged on the stepped portion 2331 for accommodating the foaming glue. After the stepped portion 2331 and the lapping portion 1231 are lapped and embedded, the foaming glue is injected at the lapped portion of the two, and the foaming glue flows into the groove 2333 and expands, and finally completely fills the groove 2333 and all gaps at the lapped portion of the two, so as to realize the sealing connection of the stepped portion 2331 and the lapping portion 1231, and prevent the gas in the box exhaust passage 12 from overflowing from the lapped portion of the stepped portion 2331 and the lapping portion 1231.

[0046] Reference Figure 1 In some possible embodiments provided by the utility model, the battery pack 0 comprises the buffer chamber 6 arranged on one side of the battery pack 0 along the first direction, that is, the Y direction.

[0047] In the embodiment, when the vehicle is hit, in order to avoid the battery pack 0 from shaking, oscillating in the first direction, i.e., the Y direction, and causing safety hazards, the buffer chamber 6 provides buffering for the cell module, so that the battery pack 0 also has high safety and reliability when hit.

[0048] With reference to the foregoing Figure 1 In some possible embodiments of the utility model, a separation partition plate 7 is arranged in the buffer chamber 6 along the height direction, i.e., the Z direction, and the buffer chamber 6 is divided into a plurality of sub-chambers 61, one of which is the box exhaust passage 12.

[0049] In the embodiment, the buffer chamber 6 is provided with a plurality of separation partition plates 7 along the height direction, i.e., the Z direction. The separation partition plate 7 is a horizontal plate, i.e., a plate extending along the first direction, i.e., the Y direction, which can enhance the strength of the battery pack 0 in the first direction, i.e., the Y direction, and prevent safety hazards when the battery pack 0 is hit.

[0050] One of the buffer chambers 6 is the box exhaust passage 12. That is, the box exhaust passage 12 can be any one of the buffer chambers 6, which can be specifically designed according to customer requirements, and correspondingly, the height of the busbar groove 23 also needs to be adjusted.

[0051] Exemplarily, with reference to Figure 1 , three separation partition plates 7 (including two separation partition plates 7 and the top plate 123 of the box exhaust passage 12) are arranged in the buffer chamber 6, and the buffer chamber 6 is divided into four sub-chambers 61. The sub-chamber 61 at the bottom is the box exhaust passage 12, and the side surface of the sub-chamber 61 at the bottom is provided with a second air vent 122. The side surface of the busbar groove 23 is provided with a first air vent 231. In the embodiment, the height of the first air vent 231 does not exceed the top plate 123 of the sub-chamber 61 at the bottom, i.e., the box exhaust passage 12. In this way, the busbar groove 23 can be sealed and connected with the box exhaust passage 12, and the gas can be discharged from the sub-chamber 61 at the bottom, i.e., the box exhaust passage 12, out of the battery pack 0.

[0052] For example, the second sub-chamber from the bottom is the box exhaust passage, and the side surface of the sub-chamber is provided with a second air vent. The height of the busbar groove at least exceeds the top plate of the sub-chamber at the bottom. The side surface of the busbar groove is provided with a first air vent. In this way, the busbar groove can be sealed and connected with the box exhaust passage, and the gas can be discharged from the sub-chamber out of the battery pack.

[0053] It should be noted that the number of the box explosion-proof valve 10 in the utility model can be increased or decreased according to specific circumstances, and the position of the box explosion-proof valve 10 can be changed according to specific circumstances. Exemplarily, for example, when the bottommost sub-chamber 61 is the box exhaust passage 12, the box explosion-proof valve 10 is arranged on the outer wall of the bottommost sub-chamber 61. For another example, when the second sub-chamber from bottom to top is the box exhaust passage, the box explosion-proof valve is arranged on the outer wall of the second sub-chamber from bottom to top.

[0054] Reference Figure 3 And Figure 4 In some possible embodiments provided by the utility model, the electric core tray 2 is provided with a flange 24 extending along the circumference thereof, the flange 24 protrudes from the electric core tray 2 towards the box bottom plate 11, and the flange 24 is placed on the box bottom plate 11, so that the electric core tray 2 has a gap 4 (as shown in the figure) in the height direction, i.e. the Z direction, with the box bottom plate 11. Figure 1

[0055] In the embodiment, the flange 24 is arranged on the electric core tray 2 and placed on the box bottom plate 11, which is equivalent to virtually raising the electric core tray 2, so that the flange 24 has a gap 4 in the height direction, i.e. the Z direction, with the upper surface of the box bottom plate 11. That is, the lower surface of the bottom surface of the electric core tray 2 is not directly attached to the box bottom plate 11, i.e. the gas inlet hole 21 is not directly attached to the box bottom plate 11, so the gas inlet hole 21 is not blocked by the box bottom plate 11. The gas released by the electric core 3 can flow into the gap 4 between the electric core tray 2 and the box bottom plate 11 through the gas inlet hole 21, effectively preventing the safety problem of the battery pack 0 caused by the thermal runaway of the electric core 3.

[0056] Reference Figure 5 In some possible embodiments provided by the utility model, the electric core 3 comprises a shell 31, an electric core explosion-proof valve 32 and an electric core busbar 33. The shell 31 is used for protecting the electric core 3. The electric core explosion-proof valve 32 is arranged at the bottom of the electric core 3 and corresponds to the gas inlet hole 21. The electric core busbar 33 is arranged in the height direction, i.e. the Z direction, apart from the shell 31, forming an electric core exhaust passage 34, and the gas in the electric core 3 is discharged through the electric core exhaust passage 34 and the electric core explosion-proof valve 32 and enters the gas inlet hole 21.

[0057] In the embodiment, the gas released by the electric core 3 when the electric core 3 is in thermal runaway will enter the electric core exhaust passage 34, and the gas in the electric core 3 will burst through the electric core explosion-proof valve 32 when the gas pressure is too large, so that the gas in the electric core 3 is discharged through the electric core explosion-proof valve 32.

[0058] Reference Figure 5 ​In some possible embodiments provided by the utility model, the bottom of the battery cell 3 is provided with a glue overflow limiting groove 30. The glue overflow limiting groove 30 is used for receiving sealing substances. Exemplarily, the sealing substance is foaming glue. Specifically, when the foaming glue is injected into the bottom of the battery cell 3, the foaming glue will finally only stay in the glue overflow limiting groove 30 after foaming and expanding, and will not foam and expand to the battery cell explosion valve 32, and naturally will not block, block or hinder the normal opening of the battery cell explosion valve 32. At the same time, the foaming glue also seals the bottom of the battery cell 3, preventing the gas released from the battery cell explosion valve 32 from escaping from the unintended place. The expected exhaust path in the battery cell 3 includes a battery cell exhaust channel 34 between the battery cell busbar 33 and the shell 31 of the battery cell 3, and the battery cell explosion valve 32. The rest are all unintended places, i.e. unintended exhaust channels.

[0059] In the embodiment, the battery pack 0 is provided with both the groove 2333 on the busbar groove 23 and the glue overflow limiting groove 30 at the bottom of the battery cell 3, effectively avoiding the blocking of the exhaust channel (including the battery cell explosion valve 32 and the box exhaust channel 12) of the CTP module of the cylindrical battery cell 3 during glue pouring, causing the gathering thermal runaway explosion phenomenon, and improving the safety of the battery pack 0.

[0060] Reference Figures 1 to 3 In some possible embodiments provided by the utility model, the busbar groove 23 is provided with a pressure sensor 8 for detecting the air pressure value of the busbar chamber 232 defined by the busbar groove 23. The battery pack 0 includes a battery management system (not shown in the figure), the battery management system is connected with the pressure sensor 8, and the battery management system is used for comparing the air pressure value with a preset air pressure value, and outputting a predetermined warning signal if the air pressure value exceeds the preset air pressure value. And / or, in the battery pack 0, the mica paper 9 is arranged between the battery cell 3 and the battery cell tray 2 along the height direction, i.e. the Z direction, and the mica paper 9 is sealingly connected with the battery cell tray 2.

[0061] In some possible embodiments, the busbar groove 23 is provided with a pressure sensor 8 for detecting the air pressure value of the busbar chamber 232 defined by the busbar groove 23. The battery pack 0 includes a battery management system, the battery management system is connected with the pressure sensor 8, and the battery management system is used for comparing the air pressure value with a preset air pressure value, and outputting a predetermined warning signal if the air pressure value exceeds the preset air pressure value.

[0062] In the embodiment, when high-pressure gas enters the busbar chamber 232 formed by the busbar groove 23 when the battery cell 3 loses control, the pressure sensor 8 can give an early warning in the first time, and output a predetermined warning signal through the battery management system, prompting the user that the battery pack 0 may have a thermal runaway problem, so that the user can find the possible safety problem of the battery pack 0 in time, and the safety level of the battery pack 0 is further improved.

[0063] Exemplarily, the predetermined warning signal comprises a whole vehicle alarm signal.

[0064] With reference to Figure 3 In some possible embodiments, the mica paper 9 is arranged between the cell 3 and the cell tray 2 in the height direction, i.e., the Z direction, and is in sealing connection with the cell tray 2.

[0065] The mica paper 9 has high-temperature-resistant insulation performance and can protect the bottom of the cell 3. In particular, when thermal runaway occurs in the cell 3, the mica paper 9 can effectively prevent the cell tray 2 from being ignited by the high-pressure gas spouted in an instant and trigger thermal runaway of other cells 3 on the cell tray 2. At the same time, the mica paper 9 can effectively prevent the gas or particles entering the air inlet hole 21 from rebounding onto the runaway cell 3 or the cell explosion valve 32 at the bottom of other normal cells 3, preventing thermal runaway of other cells 3 on the cell tray 2 and protecting other normal cells 3.

[0066] The mica paper 9 is relatively weak, and when the cell explosion valve 32 discharges gas, the gas can break through the mica paper 9 and enter the air inlet hole 21, and then enter the gap 4, the busbar groove 23 and the battery pack exhaust channel 12, and be discharged from the battery pack 0 through the exhaust outlet 121, thereby ensuring the reliability of the exhaust and improving the safety performance of the battery pack 0.

[0067] With reference to Figure 1 And Figure 2 In some possible embodiments, the busbar groove 23 is provided with a pressure sensor 8 for detecting the air pressure value of the busbar chamber 232 defined by the busbar groove 23. The battery pack 0 comprises a battery management system, the battery management system is connected with the pressure sensor 8, and the battery management system is used for comparing the air pressure value with a preset air pressure value. If the air pressure value exceeds the preset air pressure value, the battery management system outputs a predetermined warning signal. In the battery pack 0, the mica paper 9 is arranged between the cell 3 and the cell tray 2 in the height direction, i.e., the Z direction, and is in sealing connection with the cell tray 2.

[0068] In the embodiment, the battery pack 0 is provided with both the battery management system and the mica paper 9, and has the technical effects of the battery management system and the mica paper 9. The safety performance of the battery pack 0 is further improved.

[0069] In the utility model, three-stage exhaust channels are arranged in the battery pack 0, which are the cell-level exhaust channel, the module-level exhaust channel and the battery pack-level exhaust channel.

[0070] The electric core 3 includes a shell 31, an electric core explosion-proof valve 32, and an electric core busbar 33, and an electric core exhaust passage 34. The gas generated by the thermal runaway inside the electric core 3 is released through the electric core exhaust passage 34 and the electric core explosion-proof valve 32, and the first heat dissipation exhaust, i.e., the electric core level exhaust, is performed.

[0071] The high-pressure gas released by the electric core 3 through the electric core explosion-proof valve 32 continues to penetrate the mica paper 9 into the gas inlet hole 21 and the gap 4. At this time, part of the heat is dissipated by the aluminum box bottom plate 11, and most of the heat is diffused to the surrounding, and is gathered at the busbar groove 23. When the pressure at the busbar groove 23 exceeds the standard, the pressure sensor 8 will start the early warning function, and wake up the battery management system (Battery Management System, abbreviated as BMS) to interact with the vehicle control unit (Vehicle Control Unit, abbreviated as VCU). The vehicle control unit will take safety precautions for the vehicle engine. At this time, the second heat dissipation exhaust, i.e., the module level exhaust, is completed.

[0072] The high-pressure gas continues to diffuse from the busbar groove 23 to the box exhaust passage 12. When the gas enters the box exhaust passage 12, the aluminum profile box frame will perform the third heat dissipation exhaust, i.e., the battery pack level exhaust. The gas cooled by three times is discharged from the battery pack 0 through the box explosion-proof valve 10 on the box 1. In this process, the exhaust passage operates throughout the process, effectively separates the heat and electricity, and avoids the risk of gas overflow into the battery pack 0, causing other components to lose control.

[0073] It should be pointed out that the exhaust path design of the utility model is applicable to the battery pack 0 provided with different numbers of electric cores 3. That is, the exhaust path designed by the utility model does not limit the number of electric cores 3.

[0074] Although the utility model has been illustrated and described with reference to certain preferred embodiments thereof, it should be understood by those skilled in the art that the above is a further detailed description of the utility model in combination with specific embodiments, and cannot be regarded as limiting the specific implementation of the utility model to these descriptions. Those skilled in the art can make various changes in form and details, including making a number of simple inferences or substitutions, without departing from the spirit and scope of the utility model.

Claims

1. A battery pack, characterized by, The battery pack comprises: a box bottom plate; an exhaust outlet; a cell tray for carrying cells, the cell tray is placed on the box bottom plate and has a gap in the height direction with the box bottom plate, the cell tray is provided with an air inlet hole on the side which receives the cells, the air inlet hole is communicated with the cells and the gap respectively, a busbar groove is provided at the notch of one side of the cell tray, the busbar groove protrudes towards the cells, and the busbar groove is communicated with the gap and the exhaust outlet respectively; the gas released from the cells enters the gap through the air inlet hole and is discharged from the exhaust outlet through the busbar groove.

2. The battery pack of claim 1, wherein, The battery pack comprises a box exhaust channel which is arranged on one side of the battery pack along a first direction, the first direction is perpendicular to the height direction, and the box exhaust channel is provided with the exhaust outlet; the busbar groove is connected with the box exhaust channel in a butt joint manner.

3. The battery pack of claim 2, wherein the busbar groove is provided with a first air vent on the side surface thereof; the box exhaust channel is provided with a second air vent on the side surface thereof, and the second air vent is connected with the first air vent in a sealed joint manner; 4. The battery pack of claim 2, wherein, the busbar groove and the box exhaust channel form an exhaust chamber in a butt joint manner, and the top plate of the busbar groove is overlapped with the top plate of the box exhaust channel; the top plate of the busbar groove is provided with a step portion, the top plate of the box exhaust channel is provided with an overlapping portion, the step portion is embedded with the overlapping portion and connected in a sealed joint manner to prevent the gas from overflowing from the top of the exhaust chamber.

5. The battery pack of claim 4, wherein, a groove is arranged on the tread of the step portion to fill a sealing material so as to seal the step portion and the overlapping portion.

6. The battery pack of claim 2, wherein, The battery pack comprises a buffer chamber which is arranged on one side of the battery pack along the first direction.

7. The battery pack of claim 6, wherein, a partition plate is arranged in the buffer chamber along the height direction to divide the buffer chamber into a plurality of sub-chambers, and one of the sub-chambers is the box exhaust channel.

8. The battery pack of claim 1, wherein, The cell tray is provided with a flange which extends along the circumferential direction of the cell tray, the flange protrudes from the cell tray towards the box bottom plate, and the flange is placed on the box bottom plate so that the cell tray and the box bottom plate have the gap in the height direction.

9. The battery pack of claim 1, wherein, The cell comprises: a shell for protecting the cell; a cell explosion-proof valve which is arranged at the bottom of the cell and corresponds to the air inlet hole; a cell busbar which is arranged in the height direction with the shell to form a cell exhaust channel, and the gas inside the cell is discharged through the cell exhaust channel, the cell explosion-proof valve and the air inlet hole.

10. The battery pack of claim 1, wherein the busbar groove is provided with a pressure sensor for detecting the air pressure value of the busbar cavity defined by the busbar groove; the battery pack comprises a battery management system which is connected with the pressure sensor, and the battery management system is used to compare the air pressure value with a preset air pressure value, and if the air pressure value exceeds the preset air pressure value, the battery management system outputs a predetermined warning signal; and / or a mica paper is arranged between the cell and the cell tray along the height direction, and the mica paper is connected with the cell tray in a sealed joint manner.

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