Battery cell assembly and battery pack
A ring-shaped battery cell assembly with internal pressure relief valves and liquid cooling channels addresses space and thermal inefficiencies, enhancing safety and energy density.
Patent Information
- Application Number
- CN202422253217.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-13
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2034-09-13
AI Technical Summary
Traditional battery cells have low space utilization, mechanical strength, and poor thermal management, with safety risks due to exposed pressure relief valves and inadequate cooling.
A ring-shaped battery cell assembly with internal pressure relief valves and integrated liquid cooling channels, enhancing structural integrity and thermal management.
Improves energy density and safety by reducing the risk of valve failure and enabling efficient thermal dissipation, while maintaining compact design and high mechanical strength.
Smart Images
Figure CN223109141U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of batteries, and in particular to a battery cell assembly and a battery pack. Background Art
[0002] As Figure 1 and Figure 2 shown, the space utilization rate of the traditional battery cell 1' is relatively low, a large space needs to be reserved in the area near the explosion-proof valve 11' inside the package, and the mechanical strength of the traditional battery cell 1' is relatively low. When the explosion-proof valve 11' is close to the outside and is subjected to an external force, it is easy to cause the battery cell to leak liquid, and the heat dissipation performance is poor, which is likely to cause problems such as thermal runaway of the battery pack. Summary of the Utility Model
[0003] The purpose of this application is to provide a battery cell assembly and a battery pack, which to a certain extent solve the technical problems in the prior art that the space utilization rate of the traditional battery cell is low, the explosion-proof valve is located outside and is easily opened by force, resulting in liquid leakage, and the heat dissipation performance is poor.
[0004] This application provides a battery cell assembly, including: a plurality of battery cells, and the plurality of battery cells are enclosed to form an internally hollow ring structure, and an explosion-proof valve is provided on the inner side of any one of the battery cells close to the hollow part.
[0005] In the above technical solution, further, the structures of all the battery cells are the same, and the cross-section of any one of the battery cells along its height direction is an isosceles trapezoid.
[0006] In any of the above technical solutions, further, the number of the battery cells is six, and they are sequentially enclosed and abutted against each other.
[0007] In any of the above technical solutions, further, the length of the lower base of the cross-section of the battery cell is a, the length of the upper base of the cross-section of the battery cell is b, the height of the battery cell is H, and a = (0.25 - 0.8) × H, b = (0.15 - 0.5) × H, and b < a.
[0008] In any of the above technical solutions, further, the radius of the chamfer of the upper base angle of the cross-section of the battery cell is r, and r = 1 - 2 mm.
[0009] In any of the above technical solutions, further, the thickness of the housing of the battery cell is t1, and t1 = 0.3 - 0.6 mm.
[0010] In any of the above technical solutions, further, the number of the explosion-proof valves is one or more, and when the number of the explosion-proof valves is multiple, they are sequentially spaced along the height direction of the battery cell.
[0011] In any of the above technical solutions, further, the number of the explosion-proof valves is two, and they are respectively arranged close to both ends of the battery cell along the height direction of the battery cell.
[0012] In any of the above technical solutions, further, any one of the explosion-proof valves is waist-shaped, and the length of the straight region of the explosion-proof valve is c, and c = (0.3 - 0.6) × b, where b is the length of the upper base of the cross-section of the battery cell.
[0013] In any of the above technical solutions, further, the width of the explosion-proof valve is d, and d = (0.3 - 0.6) × c.
[0014] In any of the above technical solutions, further, along the height direction of the battery cell, the distance between the center of one of the explosion-proof valves and the bottom of the battery cell is e, and e = (0.1 - 0.15) × H.
[0015] In any of the above technical solutions, further, the distance between the centers of the two explosion-proof valves is f, and f = (0.4 - 0.5) × H.
[0016] The present application also provides a battery pack, including the battery cell assembly described in any of the above technical solutions. Therefore, it has all the beneficial technical effects of this battery cell assembly, which will not be elaborated here.
[0017] In any of the above technical solutions, further, the battery pack further includes a liquid cooling pipe, and the liquid cooling pipe is arranged in the hollow part inside any one of the battery cell assemblies, and a gap is formed between the liquid cooling pipe and the battery cell.
[0018] In any of the above technical solutions, further, the cross-section of any one of the battery cells along its height direction is an isosceles trapezoid, the length of the upper base of the cross-section of the battery cell is b, the inner diameter of the liquid cooling pipe is D1, and 0.8 × b ≤ D1 ≤ b.
[0019] In any of the above technical solutions, further, the thickness of the liquid cooling pipe is t2, and t2 = 0.2 - 2 mm.
[0020] In any of the above technical solutions, further, the center of the liquid cooling pipe coincides with the center of the annular structure formed by a plurality of the battery cells.
[0021] Compared with the prior art, the beneficial effects of the present application are:
[0022] The battery cell assembly provided by the present application is formed by surrounding multiple battery cells into an annular structure, which has strong structural strength and can withstand abnormal deformation caused by extrusion or vibration during the use of the battery pack. The explosion-proof valve is arranged inside the battery cell, that is, the explosion-proof valve is located in the hollow part of the annular structure, which can reduce the risk of the explosion-proof valve cracking and opening due to external force on the outside, and at the same time does not affect the normal ejection of the explosion-proof valve when the internal pressure of the battery cell is too high. Moreover, there is no need to reserve space for avoiding the explosion-proof valve, thereby reducing the gap between the battery cell and the side beam, and greatly improving the energy density of the battery pack.
[0023] In addition, multiple battery cells are surrounded into a structure with a hollow interior, and the hollow interior can also be used as a heat dissipation channel to quickly dissipate heat from the battery cell assembly, ensuring the performance of the battery pack during use. Preferably, a liquid cooling pipe can also be installed in the hollow interior surrounded by multiple battery cells to enhance the cooling effect. Description of the Drawings
[0024] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.
[0025] Figure 1 It is a schematic structural diagram of a traditional battery cell provided by the prior art;
[0026] Figure 2 It is a schematic structural diagram of a battery cell provided by an embodiment of the present application;
[0027] Figure 3 It is Figure 2 A cross-sectional view along the A-A section;
[0028] Figure 4 It is Figure 2 An enlarged structural diagram at B;
[0029] Figure 5 It is another schematic structural diagram of a battery cell provided by an embodiment of the present application.
[0030] Reference Signs:
[0031] 1'-Traditional battery cell, 11'-Explosion-proof valve;
[0032] 1-Battery cell, 11-Explosion-proof valve, 2-Liquid cooling pipe. Detailed Embodiments
[0033] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments.
[0034] Generally, the components of the embodiments of the present application described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application.
[0035] All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts fall within the scope of protection of the present application.
[0036] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present application. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0037] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.
[0038] Next, refer to Figures 2 to 5 Describe a battery cell assembly and a battery pack according to some embodiments of the present application.
[0039] Embodiment 1
[0040] Refer to Figure 2 and Figure 3 As shown, the embodiments of the present application provide a battery cell assembly, including: a plurality of battery cells 1, and the plurality of battery cells 1 are arranged to form an internally hollow ring structure, and an explosion-proof valve 11 is provided on the inner side of any battery cell 1 close to the hollow part.
[0041] According to the structure described above, the cell assembly provided by the present application is formed by surrounding multiple cells 1 into an annular structure, which has strong structural strength and can withstand abnormal deformation generated during the use of the battery pack due to extrusion, vibration, etc. Moreover, the explosion-proof valve 11 is arranged inside the cell 1, that is, the explosion-proof valve 11 is located in the hollow part of the annular structure, which can reduce the risk of the explosion-proof valve 11 cracking and opening due to external force on the outside. At the same time, it does not affect the normal ejection of the explosion-proof valve 11 when the internal pressure of the cell 1 is too high, and there is no need to reserve space for avoiding the explosion-proof valve 11, thereby reducing the gap between the cell 1 and the side beam, greatly improving the energy density of the battery pack. In addition, multiple cells 1 are surrounded into a structure with a hollow interior, and the hollow interior can also be used as a heat dissipation channel to quickly dissipate heat from the cell assembly and ensure the use performance of the battery pack.
[0042] In this embodiment, preferably, as Figure 2 shown, the structures of all the cells 1 are the same, and the cross-section of any cell 1 along its height direction is an isosceles trapezoid, and the short side of the trapezoidal cross-section corresponds to the inside of the cell 1.
[0043] According to the structure described above, the structures of all the cells 1 are the same, and the cross-section of any cell 1 along its height direction is an isosceles trapezoid. All the cells 1 can be uniformly processed and manufactured according to the same size, greatly improving the processing efficiency, and helping to improve the assembly accuracy of multiple cells 1 and the assembly efficiency.
[0044] Further, preferably, as Figure 2 shown, the number of cells 1 is six, and they are surrounded and abutted against each other in sequence. That is to say, six cells 1 are surrounded into a hexagonal annular structure.
[0045] According to the structure described above, six cells 1 are assembled together more firmly, and the size of each cell 1 is appropriate for processing and manufacturing. Moreover, when six cells 1 are assembled together, a hexagonal hollow structure can be formed, which has sufficient heat exchange space and improves the heat dissipation effect of the cells 1.
[0046] It should be noted that: the cross-section of any cell 1 along its height direction is not limited to an isosceles trapezoid, but can also be other types of trapezoidal structures, or other shaped structures. For example: the cross-section of any cell 1 along its height direction is a hexagon, an octagon or a fan-shaped ring, etc. Moreover, the structures of each cell 1 are not limited to being the same, and can also be designed according to actual needs.
[0047] In addition, the number of cells 1 is not limited to six, and can also be less than six, such as: four, etc., or greater than six, etc.
[0048] As described above, this battery cell assembly can also be structured such that four hexagonal battery cells enclose a structure with a square inner ring, or four isosceles trapezoid-shaped battery cells enclose a structure with a square inner ring. The battery cell assembly can also be structured such that three, four, five, six, or more than six fan-shaped ring battery cells, such as seven or eight fan-shaped ring battery cells, enclose a structure with a circular inner ring. Of course, the above are only a few examples and are not limited thereto. It can also be designed according to actual needs.
[0049] In this embodiment, preferably, as Figure 2 shown, the length of the lower base of the cross-section of battery cell 1 is a, the length of the upper base of the cross-section of battery cell 1 is b, and the height of battery cell 1 is H, and a = (0.25 - 0.8) × H, b = (0.15 - 0.5) × H, and b < a.
[0050] According to the structure described above, a suitable proportional relationship is established between the side lengths of the inner and outer sides of battery cell 1 and the height dimension of battery cell 1, making the overall dimension ratio of battery cell 1 more appropriate, thereby making the overall strength of battery cell 1 higher, and it also has important guiding significance for later production and improves production efficiency. Of course, this is only an example and is not limited thereto. It can also be designed according to actual needs.
[0051] In this embodiment, preferably, as Figure 4 shown, the radius of the chamfer at the upper base angle of the cross-section of battery cell 1 is r, and r = 1 - 2 mm, which ensures the strength of a single battery cell 1 and avoids stress concentration at the R corner of battery cell 1.
[0052] In this embodiment, preferably, as Figure 2 shown, the thickness of the housing of battery cell 1 is t1, and t1 = 0.3 - 0.6 mm, which ensures that battery cell 1 has sufficient strength and hardness and can effectively resist deformation. Of course, this is only an example and is not limited thereto. It can also be designed according to actual needs.
[0053] In this embodiment, preferably, as Figure 3 shown, the number of explosion-proof valves 11 is multiple, and they are sequentially arranged at intervals along the height direction of battery cell 1.
[0054] According to the structure described above, multiple explosion-proof valves 11 are provided inside battery cell 1, which play a role in quickly exhausting gas when battery cell 1 is in thermal runaway.
[0055] It should be noted that: not only limited to the above structure of multiple explosion-proof valves 11, when the height of battery cell 1 is relatively small, only one explosion-proof valve 11 can also be provided, which is specifically designed according to actual needs.
[0056] In this embodiment, preferably, as Figure 3As shown, the number of explosion-proof valves 11 is two, and they are respectively arranged near both ends of the battery cell 1 along the height direction of the battery cell 1.
[0057] According to the structure described above, cavities will be formed at both ends inside the housing of the battery cell 1. This cavity is mainly designed due to the internal lamination arrangement. This cavity area is prone to gas concentration when the battery cell 1 is abnormal. Therefore, by arranging the explosion-proof valves 11 near both ends of the battery cell 1, rapid exhaust can be achieved. If the explosion-proof valves 11 are arranged at other positions, it may occur that the internal pressure of the battery cell 1 is too high, but the explosion-proof valves 11 still do not open, resulting in a great potential safety hazard. It can be seen that arranging the two explosion-proof valves 11 near both ends of the battery cell 1 respectively facilitates rapid exhaust during thermal runaway and is safer and more reliable. Of course, this is only an example and is not limited to this, and it can also be designed according to actual needs.
[0058] It should be noted that: the number of explosion-proof valves 11 is not limited to two. The number of explosion-proof valves 11 can also be one, or the number of explosion-proof valves 11 can be more than two, such as three or four, etc.
[0059] In this embodiment, preferably, as Figure 3 shown, any explosion-proof valve 11 is waist-shaped, and the length of the straight region of the explosion-proof valve 11 is c, and c = (0.3 - 0.6) × b, where b is the length of the upper base of the cross-section of the battery cell 1;
[0060] The width of the explosion-proof valve 11 is d, and d = (0.3 - 0.6) × c.
[0061] According to the structure described above, the explosion-proof valve 11 designed according to the above proportional relationship ensures that the explosion-proof valve 11 has an appropriate length. That is to say, it can effectively avoid the explosion-proof valve 11 being too short, and then ensure that it has an appropriate exhaust area to rapidly exhaust gas when the battery cell 1 is in thermal runaway. Moreover, it provides guidance for the later selection or manufacture of the explosion-proof valve 11, and can also effectively avoid the explosion-proof valve 11 being too long, resulting in the explosion-proof valve 11 being easily affected by external loads and suffering from abnormal failure. Of course, this is only an example and is not limited to this, and it can also be designed according to actual needs.
[0062] In this embodiment, preferably, as Figure 3 shown, along the height direction of the battery cell 1, the distance between the center of one explosion-proof valve 11 and the bottom of the battery cell 1 is e, and e = (0.1 - 0.15) × H;
[0063] The distance between the centers of the two explosion-proof valves 11 is f, and f = (0.4 - 0.5) × H.
[0064] According to the structure described above, it can be known that cavities will be formed at both ends inside the housing of the battery cell 1. This cavity is mainly designed due to the internal lamination arrangement. This cavity area is prone to gas concentration when the battery cell 1 is abnormal. Therefore, the explosion-proof valves 11 are arranged at these two positions, which can quickly open for exhaust. If the explosion-proof valves 11 are arranged at other positions, it may occur that the internal pressure of the battery cell 1 is too high, but the explosion-proof valves 11 still do not open, resulting in a great potential safety hazard. It can be seen that in this application, the two explosion-proof valves 11 are respectively distributed near both ends of the battery cell 1, which is convenient for rapid exhaust during thermal runaway and is safer and more reliable. Of course, this is only an example and is not limited to this, and it can also be designed according to actual needs.
[0065] Embodiment 2
[0066] Embodiment 2 of this application also provides a battery pack, including the battery cell assembly described in Embodiment 1 above. Therefore, it has all the beneficial technical effects of this battery cell assembly, and the same technical features and beneficial effects will not be repeated.
[0067] In this embodiment, preferably, as Figure 5 shown, the battery pack further includes a liquid cooling pipe 2, and a liquid cooling pipe 2 is arranged in the internal hollow part of any battery cell assembly, and a gap is formed between the liquid cooling pipe 2 and the battery cell 1.
[0068] According to the structure described above, it can be known that in this application, the coolant flow channel is arranged in the internal hollow part of the annular structure surrounded by multiple battery cells 1. Therefore, the size in the height direction of the battery pack can be further compressed, so that the battery pack has a higher energy density. Moreover, the coolant can cool the inner side of the battery cell 1 on a large area, greatly improving the cooling effect of the battery pack and the performance of the battery pack. And a gap is formed between the liquid cooling pipe 2 and the battery cell 1, which ensures that the internal space of the grouped battery cells 1 does not affect the normal ejection of the explosion-proof valves 11, and at the same time enables effective heat exchange between the battery cell 1 and the pipe.
[0069] In this embodiment, preferably, as Figure 5 shown, the cross-section of any battery cell 1 along its height direction is an isosceles trapezoid, the length of the upper base of the cross-section of the battery cell 1 is b, the inner diameter of the liquid cooling pipe 2 is D1, and 0.8×b≤D1≤b; the thickness of the liquid cooling pipe 2 is t2, and t2 = 0.2 - 2mm.
[0070] According to the structure described above, designing the size of the liquid cooling pipe 2 according to the above proportional relationship ensures that the internal space of the grouped battery cells 1 does not affect the normal ejection of the explosion-proof valves 11, enables effective heat exchange between the battery cell 1 and the pipe, and has guiding significance for later production.
[0071] Further, preferably, the center of the liquid cooling pipe 2 coincides with the center of the annular structure formed by enclosing a plurality of battery cells 1, that is, the center of the liquid cooling pipe 2 coincides with the center of the hexagonal inner ring structure, ensuring that the gap between the liquid cooling pipe 2 and each battery cell 1 is the same, that is, ensuring that there is a sufficient gap between the liquid cooling pipe 2 and each battery cell 1, serving as an avoidance space for the normal ejection of the explosion-proof valve 11 and forming an effective heat exchange channel.
[0072] Further, preferably, the battery pack further includes a total input pipeline, a sub-input pipeline, a return sub-pipeline, and a return total pipeline. Each liquid cooling pipe 2 is provided with a sub-input pipeline and a return sub-pipeline, which are respectively arranged at both ends of the liquid cooling pipe 2, and all the sub-input pipelines are finally connected to the total input pipeline, and all the return sub-pipelines are finally connected to the return total pipeline for forming a circulating flow of the coolant. Of course, this is only an example and is not limited thereto. It is specifically designed according to actual needs.
[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A battery cell assembly, characterized in that, Including: A plurality of battery cells, and the plurality of battery cells are arranged to form a ring structure with a hollow interior, and an explosion-proof valve is provided on the inner side of any one of the battery cells near the hollow part.
2. The cell assembly according to claim 1, wherein All the battery cells have the same structure, and the cross-section of any one of the battery cells along its height direction is an isosceles trapezoid.
3. The cell assembly according to claim 2, wherein, The number of the battery cells is six, and they are sequentially arranged in a ring and abutted against each other.
4. The cell assembly according to claim 3, wherein, The length of the lower base of the cross-section of the battery cell is a, the length of the upper base of the cross-section of the battery cell is b, the height of the battery cell is H, and a = (0.25 - 0.8)×H, b = (0.15 - 0.5)×H, and b < a; And / or, the radius of the chamfer of the upper base angle of the cross-section of the battery cell is r, and r = 1 - 2 mm; And / or, the thickness of the housing of the battery cell is t1, and t1 = 0.3 - 0.6 mm.
5. The cell assembly according to claim 1, wherein The number of the explosion-proof valves is one or more, and when the number of the explosion-proof valves is more than one, they are sequentially arranged at intervals along the height direction of the battery cell.
6. The cell assembly according to claim 5, wherein The number of the explosion-proof valves is two, and they are respectively arranged near the two ends of the battery cell along the height direction of the battery cell.
7. The cell assembly according to claim 1, characterized in that, Any one of the explosion-proof valves is waist-shaped, and the length of the straight region of the explosion-proof valve is c, and c = (0.3 - 0.6)×b, where b is the length of the upper base of the cross-section of the battery cell; And / or, the width of the explosion-proof valve is d, and d = (0.3 - 0.6)×c; And / or, along the height direction of the battery cell, the distance between the center of one of the explosion-proof valves and the bottom of the battery cell is e, and e = (0.1 - 0.15)×H; The distance between the centers of the two explosion-proof valves is f, and f = (0.4 - 0.5)×H.
8. A battery pack, characterized in that, Including the battery cell assembly according to any one of claims 1 to 7.
9. The battery pack according to claim 8, characterized in that, The battery pack further includes a liquid cooling pipe, and the liquid cooling pipe is provided in the hollow interior of any one of the battery cell assemblies, and a gap is formed between the liquid cooling pipe and the battery cell.
10. The battery pack according to claim 9, wherein, The cross-section of any one of the battery cells along its height direction is an isosceles trapezoid, the length of the upper base of the cross-section of the battery cell is b, the inner diameter of the liquid cooling pipe is D1, and 0.8×b ≤ D1 ≤ b; And / or, the thickness of the liquid cooling pipe is t2, and t2 = 0.2 - 2 mm; And / or, the center of the liquid cooling pipe coincides with the center of the ring structure formed by the plurality of battery cells.