A battery pack
By using an adhesive layer to fix the battery pack to the inner wall of the casing, a closed pressure relief cavity is formed, which solves the problem of reduced net space of the pressure relief cavity, achieves a larger pressure relief space and higher safety, and improves the overall performance of the battery pack.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CALB GROUP CO LTD
- Filing Date
- 2025-06-04
- Publication Date
- 2026-05-26
AI Technical Summary
The existing battery pack has poor pressure relief performance, resulting in a reduced net space in the pressure relief chamber. This affects the smooth pressure relief of ejected material during battery thermal runaway, posing a safety hazard.
An adhesive layer is used to fix the battery pack to the inner wall of the box, forming a closed pressure relief cavity. The explosion-proof valve is located in the pressure relief cavity. The isolation plate and support structure are eliminated, and the adhesive layer is used to separate an independent pressure relief cavity, increasing the pressure relief space.
It improves the pressure relief effect and safety of the battery pack, reduces the amount of materials used, lowers the safety risks caused by gas leakage, and enhances the structural stability and safety of the battery pack.
Smart Images
Figure CN224288445U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to a battery pack. Background Technology
[0002] Thermoelectric separation of batteries is an important direction in power battery thermal runaway protection technology. Currently, conventional thermoelectric separation solutions involve setting up an isolation plate between the battery compartment and the pressure relief chamber for separation. At the same time, additional support structures need to be set up in the pressure relief chamber to provide stable support for the isolation plate. This not only results in complex structures and high production and installation costs, but also the isolation plate and the support structure in the pressure relief chamber occupy a certain amount of pressure relief space, reducing the net space of the pressure relief chamber. This affects the smooth release of ejected material during battery thermal runaway, thus posing safety issues for the battery pack.
[0003] Therefore, how to improve the pressure relief effect and safety of battery packs is a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content
[0004] In view of this, the purpose of this application is to provide a battery pack that improves the pressure relief effect and safety of use.
[0005] To achieve the above objectives, this application provides the following technical solution:
[0006] A battery pack, characterized in that it comprises:
[0007] The box-shaped enclosure forms a closed space.
[0008] The battery pack is formed by stacking multiple individual cells. The battery pack is fixedly installed inside the box. Each individual cell is equipped with an explosion-proof valve. The explosion-proof valve faces the first side panel of the box and is spaced apart from the first side panel.
[0009] An adhesive layer is used to fix the battery pack to the inner wall of the housing and fill the gap in the battery pack. The adhesive layer and the battery pack are separated in the housing to form a pressure relief cavity with the first side plate as one side wall. The pressure relief cavity is a closed cavity and the explosion-proof valve is located in the pressure relief cavity.
[0010] As can be seen from the above technical solution, one aspect of this disclosure provides a battery pack, which has a housing providing a closed space and a battery pack disposed within the housing. The battery pack is fixed to the inner wall of the housing by an adhesive layer. The explosion-proof valves of the individual cells of the fixedly disposed battery pack face the first side plate of the housing and are spaced apart from the first side plate. The adhesive layer fills the gap area in the battery pack from the outside, connecting the battery pack to the inner wall of the housing, so as to cooperate with the battery pack and separate a closed pressure relief cavity in the housing. The explosion-proof valves of the individual cells in the battery pack are all located in the pressure relief cavity. The two opposite side walls of the pressure relief cavity are the first side plate of the housing and the filling and cooperation area of the adhesive layer and the battery pack, respectively. The circumferential side wall of the pressure relief cavity is the inner wall of the housing. No other isolation plates and support structures are required during the molding process of the pressure relief cavity, which reduces the amount of battery pack material and increases the utilization area of the pressure relief cavity, thereby improving the pressure relief effect of the battery pack and ensuring the safety of the battery pack. Attached Figure Description
[0011] To more clearly illustrate the technical solutions in the embodiments of this application 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 this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0012] Figure 1 This is an exploded view of a battery pack according to an embodiment of the present invention.
[0013] Figure 2 This is a schematic diagram of the battery packaging structure provided in one embodiment of the present invention;
[0014] Figure 3 for Figure 2 Side view of the battery pack;
[0015] Figure 4 for Figure 3 A schematic diagram of the AA cross-sectional structure in the diagram;
[0016] Figure 5 A bottom view of the battery pack with the first side panel removed, according to an embodiment of the present invention;
[0017] Figure 6 This is a schematic diagram of the connection structure between the adhesive layer and the battery pack.
[0018] Figure 7 This is a schematic diagram of the pressure relief cavity structure of a battery pack according to another embodiment of the present invention;
[0019] Figure 8 for Figure 7A front view;
[0020] Figure 9 This is a cross-sectional schematic diagram of the bonding structure between the adhesive layer and the second side plate provided in one embodiment of the present invention.
[0021] in:
[0022] 10 - Box body; 110 - First side panel; 120 - Second side panel;
[0023] 20 - Battery pack; 210 - Individual cell; 220 - Explosion-proof valve;
[0024] 30 - Adhesive layer;
[0025] 40 - Pressure relief chamber; 410 - First pressure relief chamber; 420 - Second pressure relief chamber. Detailed Implementation
[0026] The core of this application is to disclose a battery pack that improves the pressure relief effect and safety of the battery pack.
[0027] To enable those skilled in the art to better understand the present application, embodiments of the present application will be described below with reference to the accompanying drawings. Furthermore, the embodiments shown below do not limit the scope of the utility model described in the claims. Additionally, the complete content of the structures represented in the following embodiments is not limited to those necessary for the solution of the utility model described in the claims.
[0028] like Figure 1 and Figure 2 As shown, one aspect of this disclosure provides a battery pack, which mainly includes a housing 10, a battery pack 20, and an adhesive layer 30. The housing 10 serves as the outer shell of the entire battery pack, enclosing a closed space to provide a relatively independent and stable internal environment for the battery pack 20, isolating it from external moisture and dust. The battery pack 20, disposed inside the housing 10, is formed by stacking multiple individual batteries 210. The individual batteries 210 can be cylindrical or prismatic. This stacking arrangement not only makes full use of the internal space of the housing 10 and improves the overall energy density of the battery pack, but also enhances the structural stability of the battery pack 20 to a certain extent.
[0029] Meanwhile, the battery pack 20 is fixedly installed inside the housing 10, and each individual battery cell 210 contained therein is equipped with an explosion-proof valve 220. It should be noted that, in the battery pack provided in this embodiment, as... Figure 1 and Figure 5As shown, the explosion-proof valve 220 on the individual battery 210 faces the first side plate 110 of the housing 10 and is spaced apart from the first side plate 110. This allows the explosion-proof valve 220 to release pressure towards the first side plate 110 in a timely manner when the internal pressure of the individual battery 210 abnormally increases, preventing the battery from exploding due to excessive internal pressure. The adhesive layer 30 is used to fix the battery pack 20 to the inner wall of the housing 10, so that the explosion-proof valve 220 in the battery pack 20 can maintain a distance from the first side plate 110. This ensures that the explosion-proof valve 220 has sufficient space to diffuse during the release process, reducing the safety risks that may be caused by excessive gas pressure.
[0030] Specifically, the adhesive layer 30 fixes and fills the inner wall of the battery pack 20 and the housing 10 by bonding, ensuring the stable position of the battery pack 20 within the housing 10, and simultaneously... Figure 6 As shown, the adhesive layer 30 fills the gap area in the battery pack 20, that is, the individual cells 210 inside the battery pack 20 are fixed by the adhesive layer 30. The adhesive layer 30 serves two purposes: firstly, it fixes the battery pack 20 within the housing 10, enhancing the structural stability of the battery pack; secondly, as... Figure 3 and Figure 4 As shown, the adhesive layer 30 and the battery pack 20 separate a pressure relief cavity 40 within the housing 10, with the first side plate 110 as one side wall. Specifically, inside the housing 10, the first side plate 110 and the circumferential side wall of the housing 10 form a box structure with one side opening. Perpendicular to the first side plate 110, the battery pack 20 and the adhesive layer 30 extending around the battery pack 20 to the inner wall of the housing 10 seal the opening area of the aforementioned box structure, forming a closed pressure relief cavity 40 surrounding the explosion-proof valve 220. When the explosion-proof valve 220 releases pressure, gas can directly enter the pressure relief cavity 40. Because the pressure relief cavity 40 is closed, the gas will not diffuse freely to other parts of the housing 10, thereby further reducing the safety risks that may be caused by gas leakage.
[0031] It should be noted that in the above embodiment, since one side of the pressure relief cavity 40 is sealed through the cooperation structure of the battery pack 20 and the adhesive layer 30, the explosion-proof valve 220 of the individual battery 210 is directly located inside the pressure relief cavity 40, and there is no partition structure between them. This reduces the structural layers that need to be destroyed during the pressure relief process of the explosion-proof valve 220 on the individual battery 210, thus enabling rapid pressure relief of the individual battery 210. Simultaneously, the pressure relief cavity 40 is formed through the cooperation structure of the adhesive layer 30 and the battery pack 20, combined with other internal structures of the housing 10. Unlike existing technologies, it does not require partitions or supporting structures for the partitions to form a cavity. Therefore, the pressure relief cavity 40 formed in this embodiment has a larger net space, reducing the amount of battery pack material while improving the pressure relief effect of the battery pack, thus ensuring the safety of the battery pack.
[0032] Furthermore, the pressure relief cavity 40 is used to provide pressure relief space for the explosion-proof valve 220. One or more of them can be set inside the housing 10. In some embodiments of this disclosure, one pressure relief cavity 40 is set between the first side plate 110 and the battery pack 20. The explosion-proof valve 220 of each individual battery 210 is located in the same pressure relief cavity 40. The forming process of the pressure relief cavity 40 is simple, and a large pressure relief space is provided when a single explosion-proof valve 220 is depressurized and ejected.
[0033] In other embodiments of this disclosure, multiple pressure relief chambers 40 are provided between the first side plate 110 and the battery pack 20 to better cope with situations where multiple individual batteries 210 experience abnormal pressure simultaneously, and to further improve the operational safety of the battery pack. Specifically, as... Figure 7 and Figure 8 As shown, the pressure relief chamber 40 includes at least a first pressure relief chamber 410 and a second pressure relief chamber 420. Multiple explosion-proof valves 220 are respectively installed within the first and second pressure relief chambers 410 and 420 to provide zoned explosion protection for the battery pack 20. This allows for independent and effective management of abnormal pressure in individual battery cells 210 in different areas. When an abnormal pressure occurs in an individual battery cell 210 within the first pressure relief chamber 410, the gas released by the explosion-proof valve 220 will only enter the first pressure relief chamber 410 and will not affect the normal state of the second pressure relief chamber 420. The same applies when an abnormal pressure occurs in an individual battery cell 210 within the second pressure relief chamber 420. Furthermore, the independently designed multiple chamber structure not only facilitates rapid problem location and handling, reducing maintenance costs, but also prevents a pressure abnormality in one pressure relief chamber from causing a chain reaction in another, thereby enhancing the overall stability and safety of the battery pack.
[0034] It should also be noted that, in the direction perpendicular to the first side plate 110, the first pressure relief chamber 410 and the second pressure relief chamber 420 are separated by the extension structure of the adhesive layer 30. No other supporting components are needed; the extension structure of the adhesive layer 30 separates the two pressure relief chambers, ensuring a tight seal between them and preventing the pressure relief gas from flowing between them. Furthermore, the pressure relief chamber 40 with its separation structure provides greater flexibility in the design and manufacturing of the battery pack. During the design process, the size and position of the first pressure relief chamber 410 and the second pressure relief chamber 420 can be flexibly adjusted according to the specific requirements and dimensions of the battery pack, as well as the arrangement of the individual battery cells 210 inside, to achieve optimal safety performance and structural stability.
[0035] The above embodiment is only used as an example to illustrate the first pressure relief chamber 410 and the second pressure relief chamber 420 separated in the pressure relief chamber 40. The pressure relief chamber 40 can also be divided into more chamber structures of the same or different sizes, which will not be described in detail here.
[0036] To further optimize the above technical solution, in some embodiments of this disclosure, the first pressure relief chamber 410 and the second pressure relief chamber 420 have equal volumes, and the number of explosion-proof valves 220 enclosed within the first pressure relief chamber 410 and the second pressure relief chamber 420 is also equal. That is, when the pressure relief chamber 40 contains only the first pressure relief chamber 410 and the second pressure relief chamber 420, the first pressure relief chamber 410 and the second pressure relief chamber 420 equally divide the pressure relief chamber 40 and equally divide the explosion-proof valves 220 required to provide pressure relief areas in the battery pack 20. This makes the two pressure relief chambers symmetrical in structure and function, which is beneficial for the balanced layout of the internal structure of the battery pack. At the same time, the first pressure relief chamber 410 and the second pressure relief chamber 420 bear the same design pressure relief load. Combined with the comparable ability of the first pressure relief chamber 410 and the second pressure relief chamber 420 to cope with abnormal pressure in a single battery cell 210, the various regions of the battery pack have similar structures and pressure relief strength, thereby improving the uniformity of the overall performance of the battery pack.
[0037] Furthermore, in the battery pack provided in the embodiments of this disclosure, the purpose of setting the pressure relief cavity 40 is to provide space for the explosion-proof valve 220 of the individual battery 210 to meet the pressure relief requirements. Therefore, the pressure relief cavity 40 only needs to surround all the explosion-proof valves 220. In order to form a larger pressure relief space within the housing 10 to improve the safety of the battery pack, in some other embodiments of this disclosure, the projection of the pressure relief cavity 40 on the side of the battery pack 20 where the explosion-proof valves 220 are located covers and extends beyond the setting range of the explosion-proof valves 220. Specifically, taking the first side panel 110 of the housing 10 as an example, the projection of the battery pack 20 on the first side panel 110 is smaller than the area of the first side panel 110, while the sum of the projections of the first pressure relief chamber 410 and the second pressure relief chamber 420 on the first side panel 110 covers the entire area of the first side panel 110. This allows the pressure relief chamber 40 to fully utilize the area of the first side panel 110 and the structure of the housing 10, thereby providing more space for the explosion-proof valve 220 to release pressure. When the explosion-proof valve 220 releases gas, the gas can diffuse fully within the pressure relief chamber 40 with sufficient capacity, reducing the possibility of gas accumulation in local areas and lowering the safety risks that may be caused by excessive gas pressure.
[0038] In other embodiments of this disclosure, the pressure relief chambers 40 are configured in a one-to-one correspondence with individual battery cells 210. Specifically, the number of pressure relief chambers 40 is the same as the number of individual battery cells 210, and the explosion-proof valve 220 of each individual battery cell 210 is located within an independent pressure relief chamber 40. This ensures that each individual battery cell 210's explosion-proof valve 220 has an independent pressure relief space, enabling more precise management and control of the pressure of each individual battery cell 210. When the explosion-proof valve 220 of a certain individual battery cell 210 needs to release pressure, gas will only enter the pressure relief chamber 40 corresponding to that individual battery cell 210, without affecting other individual batteries 210 or the structure of the pressure relief chamber 40. It should be noted that the independent pressure relief chambers 40 not only effectively prevent a chain reaction in the entire battery pack 20 caused by a problem with one individual battery cell 210, but also greatly reduce the safety risks that may be caused by gas leakage, thereby significantly improving the safety and reliability of the battery pack.
[0039] Furthermore, adjacent pressure relief cavities 40 are separated by an extension structure of the adhesive layer 30 in a direction perpendicular to the first side plate 110. The separation of the pressure relief cavities 40 by the extension structure of the adhesive layer 30 not only reduces the amount of material used, but also ensures the sealing between each pressure relief cavity 40, preventing gas from communicating between adjacent pressure relief cavities 40.
[0040] Based on the above embodiments, while the pressure relief chamber 40 corresponds one-to-one with the individual battery 210, the cross-sectional area of the pressure relief chamber 40 in the direction perpendicular to the first side plate 110 is larger than the area of the explosion-proof valve 220. This is to account for the circumferential diffusion of gas at the location of the explosion-proof valve 220, so that the pressure relief chamber 40 can provide more space for the gas released by the explosion-proof valve 220, and prevent gas from overflowing from the docking area between the pressure relief chamber 40 and the individual battery 210 after the explosion-proof valve 220 is damaged. It should also be noted that in the direction perpendicular to the first side plate 110, the cross-sectional area of the pressure relief chamber 40 is smaller than the structural area of the side of the individual battery 210 where the explosion-proof valve 220 is located, so that the projection of a single pressure relief chamber 40 is located within the side coverage area of the individual battery 210, thereby avoiding interference with other pressure relief chambers 40 in the surrounding area. The above embodiments limit the maximum and minimum cross-sectional areas of the pressure relief chamber 40. It should be noted that, within the limit range, it is preferable that the cross-sectional area of the pressure relief chamber 40 is close to the maximum cross-sectional area, so as to provide a larger pressure relief area for the individual battery 210, improve the fault tolerance of the battery pack, and even if the explosion-proof valve 220 releases a large amount of gas or the release speed is fast, the pressure relief chamber 40 can effectively contain and handle these gases, thereby ensuring the safe operation of the battery pack as a whole.
[0041] Furthermore, in the battery pack provided in this embodiment, one side of the pressure relief cavity 40 is sealed by the cooperation structure of the adhesive layer 30 and the battery pack 20 to form a closed pressure relief cavity 40. The sealing structure on this side can be an uneven structure, that is, the adhesive layer 30 fills the gaps of the individual cells 210 in the battery pack 20 and the gap between the battery pack 20 and the inner wall of the surrounding box 10. However, in the direction perpendicular to the first side plate 110, the adhesive layer 30 is recessed into the end face of the individual cell 210 to form a sealing structure with different concavity and convexity. In other embodiments of this disclosure, the side of the adhesive layer 30 facing the first side plate 110 is flush with the end face of the single battery cell 210 where the explosion-proof valve 220 is located. This creates a smooth transition surface between the adhesive layer 30 and the closed side structure of the pressure relief cavity 40 formed by the battery pack 20. This improves the compactness and stability of the internal structure of the battery pack. During battery pack operation, when the explosion-proof valve 220 releases gas, the gas can enter the pressure relief cavity 40 more smoothly, reducing the resistance and eddy currents that may occur between the end face of the explosion-proof valve 220 and the adhesive layer 30. This avoids the dangerous situation of gas accumulating in a local area and forming a high-pressure zone. It should also be noted that the flush structure between the adhesive layer 30 and the side of the battery pack 20 also improves the appearance quality and aesthetics of the battery pack, making the overall structure of the battery pack more regular and harmonious.
[0042] Furthermore, in the battery pack provided in the embodiments of this disclosure, such as Figure 1 and Figure 3As shown, the housing 10 includes a second side plate 120 disposed opposite to the first side plate 110. The first side plate 110 and the second side plate 120 are respectively located on both sides of the battery pack 20, and in order to facilitate the assembly of the battery pack 20 inside the housing 10, the battery pack 20 is spaced apart from the first side plate 110 and the second side plate 120. Figure 9 As shown, the adhesive layer 30, in addition to fixing the inner wall of the housing 10 and the battery pack 20, extends to the second side plate 120 and adhesively fills the area between the battery pack and the second side plate 120. This allows the adhesive layer 30 to have a larger contact bond with the inner wall of the housing 10, thereby further enhancing the fixed connection strength between the battery pack 20 and the housing 10 and improving the overall rigidity of the battery pack. At the same time, since the adhesive layer 30 extends to the second side plate 120 and fills the area between it and the second side plate 120, when the battery pack is subjected to external impact or vibration at the position of the second side plate 120, the adhesive layer 30 can better disperse and absorb the force, thereby reducing damage to the battery pack 20 and the housing 10.
[0043] The above embodiment uses the adhesive layer 30 to bond the battery pack 20 to directly form the pressure relief cavity 40, which has certain operational difficulties. To reduce the production difficulty of the battery pack, in some embodiments of this disclosure, a prefabricated component is also provided inside the housing 10. The prefabricated component is used to pre-form the space required for the pressure relief cavity 40 inside the housing 10, and to realize the setting of the pressure relief cavity 40 after the battery pack is produced. Specifically, the prefabricated component has a cavity structure and at least one side wall is in contact with the explosion-proof valve 220, so that the subsequently formed pressure relief cavity 40 can communicate with the explosion-proof valve 220 of the battery pack 20 and meet the pressure relief requirements.
[0044] It should be noted that the purpose of setting the prefabricated component is to pre-isolate the space of the pressure relief cavity 40 inside the housing 10 before the adhesive layer 30 is set, and to form the pressure relief cavity 40 surrounding the explosion-proof valve 220 after the adhesive layer 30 is set. The prefabricated component can be taken out of the housing 10 after the adhesive layer 30 is set, or it can be left inside the housing 10, as long as it meets the requirement of forming the pressure relief cavity 40 surrounding the explosion-proof valve 220. In some embodiments of this disclosure, the prefabricated component is a tooling pre-coated with release agent or release wax. The prefabricated component of the tooling structure can be easily installed and positioned during the manufacturing process. It is based on the inner wall of the first side plate 110 and contacts the explosion-proof valve 220 of the battery pack 20 on one side. After the adhesive layer 30 is set, the outer side of the prefabricated component of the tooling structure is in sealed contact with the adhesive layer 30, and a cavity surrounding the explosion-proof valve 220 is formed inside. At the same time, the first side plate 110 of the housing 10 is opened to remove the tooling pre-coated with release agent or release wax. Then, the first side plate 110 is reassembled to form a closed pressure relief cavity 40 on one side of the explosion-proof valve 220. With the help of the prefabricated component of the tooling structure, the production efficiency and finished product quality of the battery pack can be improved.
[0045] In other embodiments of this disclosure, when the prefabricated component is a sealed bag filled with inert gas, the sealed bag is similarly placed inside the housing 10 before the adhesive layer 30 is installed, and one side of the sealed bag contacts the explosion-proof valve 220 of the individual battery 210, so as to reserve space for the installation of the pressure relief cavity 40 through the internal area of the sealing gasket. After the adhesive layer 30 is installed, the sealed bag remains inside the housing 10. That is, based on the adhesive layer 30, battery pack 20 and first side plate 110 forming the pressure relief cavity 40, the sealed bag is retained inside the pressure relief cavity 40. When the explosion-proof valve 220 is depressurized and ejected, the ejected material can directly destroy the sealed bag and be released in the pressure relief cavity 40 to achieve the depressurization of the individual battery 210. In addition, the installation of inert gas can also improve the pressure stability inside the pressure relief cavity 40, thereby ensuring the safe operation of the entire battery pack.
[0046] Furthermore, in some embodiments of this disclosure, the individual battery 210 is a cylindrical battery, and the axis of a single individual battery 210 is perpendicular to the first side plate 110, with multiple individual batteries 210 stacked crosswise. The explosion-proof valve 220 is disposed on the circular end face of one end of the cylindrical battery. It should be noted that the shape of the cylindrical battery allows the battery pack 20 to be arranged more tightly during stacking, increasing the overall energy density of the battery pack. Simultaneously, it maintains a certain gap between adjacent batteries, which is filled by the adhesive layer 30, thus maintaining the rigidity of the battery pack and reducing heat exchange between adjacent batteries that could affect the operational stability of the battery pack. At the same time, the axis of the cylindrical battery being perpendicular to the first side plate 110 allows the explosion-proof valve 220 to face the first side plate 110 more directly. When the explosion-proof valve 220 releases gas, the gas can enter the pressure relief chamber 40 more smoothly, reducing resistance and eddy currents that may occur during gas discharge and increasing the pressure relief speed.
[0047] Furthermore, in the battery pack provided in this embodiment, the thickness of the pressure relief cavity 40 in the direction perpendicular to the first side plate 110 is 3mm-25mm. It should be noted that the purpose of setting the thickness of the pressure relief cavity 40 to 3mm-25mm is to ensure that the pressure relief cavity 40 provides sufficient space when the explosion-proof valve 220 releases gas, while not occupying excessive internal space of the housing 10. In some embodiments of this disclosure, the thickness of the pressure relief cavity 40 is set to 3mm, 9mm, 14mm, 19mm, or 25mm, respectively, to ensure the safety performance of the battery pack while meeting the energy density stacking requirements of the battery pack. Specifically, when the explosion-proof valve 220 releases gas, the pressure relief cavity 40 needs sufficient space to contain and diffuse these gases to avoid safety risks caused by excessive gas pressure. However, given a fixed design volume of the battery pack, an excessively thick pressure relief cavity 40 will reduce the design space of the battery pack 20, thereby reducing the energy density of the battery pack. Therefore, the thickness of the pressure relief chamber 40 is set to 3mm-25mm to balance the energy density and pressure relief safety of the battery pack, thereby improving the competitiveness of the battery pack product.
[0048] Furthermore, it should be noted that in the embodiments of this disclosure, the thermal conductivity of the adhesive layer 30 connecting the battery pack 20 to the inner wall of the housing 10 is 0.02 W / (mK)-3 W / (mK). It should be noted that the thermal conductivity of the adhesive layer 30 can be set to 0.02 W / (mK), 0.8 W / (mK), 1.5 W / (mK), 2.3 W / (mK), or 3 W / (mK). The above thermal conductivity can ensure that the heat generated by the battery pack 20 can be effectively conducted to the inner wall of the housing 10 during the operation of the battery pack, thereby avoiding the battery pack 20 from affecting performance or causing safety problems due to overheating. Instead, the heat is dissipated through the heat dissipation structure of the housing 10, thereby keeping the temperature of the battery pack 20 within a reasonable range.
[0049] It should also be noted that the bonding strength of the adhesive layer 30 is 0.05MPa-15MPa, and in some embodiments of this disclosure, the bonding strength of the adhesive layer 30 can be 0.05MPa, 3.5MPa, 7.5MPa, 10.5MPa or 15MPa, so as to maintain a firm connection between the battery pack 20 and the housing 10. When the battery pack is subjected to external impact or vibration, the good bonding strength can effectively prevent the battery pack 20 from loosening or separating from the housing 10, thereby ensuring the overall structural stability of the battery pack.
[0050] The terms "first," "second," "left side," and "right side," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units may not be defined in the listed steps or units, but may include steps or units not listed.
[0051] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A battery pack, characterized in that, include: The box (10) encloses and forms a closed space; The battery pack (20) is formed by stacking multiple individual batteries (210). The battery pack (20) is fixedly installed inside the housing (10). Each individual battery (210) is provided with an explosion-proof valve (220). The explosion-proof valve (220) faces the first side plate (110) of the housing (10) and is spaced apart from the first side plate (110). An adhesive layer (30) is used to fix the battery pack (20) to the inner wall of the housing (10) and fill the gap in the battery pack (20). The adhesive layer (30) and the battery pack (20) are separated in the housing (10) to form a pressure relief cavity (40) with the first side plate (110) as one side wall. The pressure relief cavity (40) is a closed cavity and the explosion-proof valve (220) is located in the pressure relief cavity (40).
2. The battery pack as described in claim 1, characterized in that, The pressure relief chamber (40) includes at least a first pressure relief chamber (410) and a second pressure relief chamber (420). The first pressure relief chamber (410) and the second pressure relief chamber (420) respectively surround a plurality of the explosion-proof valves (220), and the first pressure relief chamber (410) and the second pressure relief chamber (420) are separated by the extension structure of the adhesive layer (30) in a direction perpendicular to the first side plate (110).
3. The battery pack as described in claim 2, characterized in that, The first pressure relief chamber (410) and the second pressure relief chamber (420) have the same volume, and the number of explosion-proof valves (220) enclosed in the first pressure relief chamber (410) and the second pressure relief chamber (420) is the same.
4. The battery pack as described in claim 2, characterized in that, The projection of the battery pack (20) on the first side plate (110) is smaller than the area of the first side plate (110), and the sum of the projections of the first pressure relief chamber (410) and the second pressure relief chamber (420) on the first side plate (110) covers the entire area of the first side plate (110).
5. The battery pack as described in claim 1, characterized in that, The pressure relief chamber (40) is provided in a one-to-one correspondence with the single cell (210). The explosion-proof valve (220) of a single cell (210) is surrounded in a single pressure relief chamber (40). Adjacent pressure relief chambers (40) are separated by the extension structure of the adhesive layer (30) in a direction perpendicular to the first side plate (110).
6. The battery pack as described in claim 5, characterized in that, In the direction perpendicular to the first side plate (110), the cross-sectional area of the pressure relief cavity (40) is larger than the area of the explosion-proof valve (220).
7. The battery pack as claimed in claim 1, characterized in that, The adhesive layer (30) is flush with the side of the first side plate (110) facing the single cell (210) where the explosion-proof valve (220) is located.
8. The battery pack as claimed in claim 1, characterized in that, The housing (10) includes a second side panel (120) disposed opposite to the first side panel (110), and the adhesive layer (30) extends to the second side panel (120) and adhesively fills the area between the battery pack and the second side panel (120).
9. The battery pack as claimed in claim 1, characterized in that, The housing (10) is provided with a prefabricated component, which is a cavity structure and has at least one side wall in contact with the explosion-proof valve (220). The prefabricated component is isolated in the housing (10) to form the pressure relief cavity (40).
10. The battery pack as claimed in claim 9, characterized in that, The preform is a tooling pre-coated with release agent or release wax, or the preform is a sealed bag filled with inert gas.
11. The battery pack as claimed in claim 1, characterized in that, The single cell (210) is a cylindrical cell, the axis of which is perpendicular to the first side plate (110), and the explosion-proof valve (220) is disposed on the circular end face of one end of the cylindrical cell.
12. The battery pack as claimed in claim 1, characterized in that, The thickness of the pressure relief cavity (40) in the direction perpendicular to the first side plate (110) is 3mm-25mm.
13. The battery pack as claimed in claim 1, characterized in that, The thermal conductivity of the adhesive layer (30) is 0.02W / (mK)-3W / (mK), and the adhesive strength is 0.05MPa-15MPa.