Battery and battery pack

Abstract

The utility model provides a kind of battery and battery pack.The battery includes: shell, with installation cavity, the bottom wall of shell is provided with pressure relief structure;Naked electric core, in installation cavity;Bottom support plate assembly, including the bottom support plate and elastic support structure installed in installation cavity, bottom support plate is set in the bottom of installation cavity and can support naked electric core, elastic support structure is elastically supported between the bottom wall of shell and bottom support plate, to make bottom support plate can be moved along first direction relative to shell, and the bottom wall of bottom support plate and shell forms exhaust passage for air flow circulation.The utility model technical scheme, can solve the problem of low exhaust rate when short knife type electric core of prior art occurs thermal runaway.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more specifically, to a battery and a battery pack. Background Technology

[0002] In today's booming market for new energy vehicles and portable electronic products, short-blade battery cells occupy an important position in battery system design due to their unique shape and performance advantages. However, the design of the explosion-proof valve for short-blade battery cells faces some inherent challenges. Unlike the traditional battery's upward-facing explosion-proof valve layout, short-blade battery cells often adopt a special design with the explosion-proof valve facing downwards. While this design helps reduce the impact of the external environment on the battery's internal structure, it also introduces new problems.

[0003] Chinese Patent 202321935563.0 discloses a battery cell, a battery pack, and an electrical device. The first wall surface has a protruding structure extending towards the interior of the receiving cavity. This protruding structure abuts against the bare battery cell, forming a flow channel between the bare battery cell and the first wall surface for fluid flow. This technical solution, by providing a protruding structure on the bottom wall of the casing (i.e., the first wall surface) to support the support plate and the bare battery cell, and forming a flow channel between the support plate and the first wall surface for fluid flow, allows gas generated during thermal runaway of the battery cell to flow smoothly through the flow channel to the pressure relief structure and be discharged outside the casing. While this technical solution allows gas generated during thermal runaway to be discharged smoothly from the casing, the exhaust space is relatively limited. In the event of thermal runaway, the large amount of gas generated inside the short-blade type battery cell is difficult to release quickly, resulting in the internal pressure being difficult to release effectively in a short time, posing a risk of battery cell explosion. Utility Model Content

[0004] The main objective of this invention is to provide a battery and battery pack that can solve the problem of low exhaust rate of short blade-type battery cells in the prior art when thermal runaway occurs.

[0005] To achieve the above objectives, according to one aspect of the present invention, a battery is provided, comprising: a housing having a mounting cavity, the bottom wall of the housing being provided with a pressure relief structure; a bare battery cell located within the mounting cavity; and a bottom support plate assembly including a bottom support plate installed within the mounting cavity and an elastic support structure, the bottom support plate being disposed at the bottom of the mounting cavity and capable of supporting the bare battery cell, the elastic support structure being elastically supported between the bottom wall of the housing and the bottom support plate, so that the bottom support plate can move relative to the housing in a first direction, and an exhaust channel for airflow is formed between the bottom support plate and the bottom wall of the housing.

[0006] Furthermore, the elastic support structure includes an elastic element that elastically abuts against the bottom wall of the housing and the bottom support plate, and the elastic element is located on the outer periphery of the pressure relief structure.

[0007] Furthermore, the base plate extends along the second direction, and there are at least two elastic elements. The at least two elastic elements are spaced apart along the second direction. The base plate assembly also includes at least two base plates. The at least two elastic elements are arranged in a one-to-one correspondence with the at least two base plates, and the elastic elements elastically abut against the base plate and the corresponding base plate.

[0008] Furthermore, the elastic element is a spring or a sheet spring.

[0009] Furthermore, the elastic element is a spring, and the base plate assembly also includes a guide post. The guide post is fixedly mounted on the base plate or the bottom wall of the housing, and the spring is sleeved on the outer periphery of the guide post. The length of the guide post is less than the minimum distance between the base plate and the bottom wall.

[0010] Furthermore, the elastic element is a spring, and the base plate assembly also includes a guide post, which is fixedly mounted on the base plate or the bottom plate. The spring is sleeved on the outer periphery of the guide post, and the length of the guide post is less than the minimum distance between the base plate and the bottom plate.

[0011] Furthermore, the battery also includes an insulating film, which includes a first covering section and a second covering section connected to each other. The first covering section is longitudinally wrapped around the outer periphery of the bare cell. The first covering section covers the bottom surface, top surface and two large surfaces of the bare cell and forms a first wrapping layer. The second covering section covers the bottom support plate assembly and at least part of the first wrapping layer and forms a second wrapping layer, so that the bottom support plate assembly is located between the part of the first wrapping layer and the second wrapping layer.

[0012] Furthermore, a first through hole is provided on the second covering section, and the first through hole is provided in correspondence with the pressure relief structure.

[0013] Furthermore, the first covering section is connected to the bottom support plate.

[0014] According to another aspect of the present invention, a battery pack is provided, comprising: a plurality of batteries as described above.

[0015] The present invention utilizes a housing, a bare battery cell, and a base plate assembly. The base plate assembly includes a base plate installed within a mounting cavity and an elastic support structure. The base plate is positioned at the bottom of the mounting cavity and supports the bare battery cell. The elastic support structure provides elastic support between the bottom wall of the housing and the base plate. The bare battery cell is placed on the base plate. At this time, the weight of the bare battery cell compresses the elastic support structure. When the battery experiences thermal runaway, it releases a large amount of gas and vapor generated by electrolyte evaporation. The gas flows through the exhaust channel to the pressure relief structure and is discharged outside the housing. As the gas is released, the weight of the bare battery cell gradually decreases. Under the elastic restoring force of the elastic support structure, the base plate can move away from the bottom wall of the housing along a first direction. At this time, the distance between the base plate and the bottom wall of the housing increases, the exhaust channel becomes larger, and the rate at which the gas in the mounting cavity is discharged outside the housing is accelerated. Attached Figure Description

[0016] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments and descriptions of this utility model are used to explain this utility model and do not constitute an undue limitation thereof. In the drawings:

[0017] Figure 1 A schematic diagram of the battery structure according to an embodiment of the present invention is shown;

[0018] Figure 2 It shows Figure 1 Sectional view at point AA;

[0019] Figure 3 It shows Figure 2 Sectional view at BB;

[0020] Figure 4 It shows Figure 3 A magnified view of a portion at point C;

[0021] Figure 5 A schematic diagram of the battery structure according to an embodiment of the present invention is shown;

[0022] Figure 6 A schematic diagram of the structure of the base plate assembly according to an embodiment of the present invention is shown;

[0023] Figure 7 A schematic diagram of the structure of the base plate assembly according to an embodiment of the present invention is shown;

[0024] Figure 8 A schematic diagram of the structure of the insulating film according to an embodiment of the present invention is shown;

[0025] Figure 9 A schematic diagram of the structure of the insulating film according to an embodiment of the present invention is shown;

[0026] Figure 10 A partial structural schematic diagram of a battery according to an embodiment of the present invention is shown;

[0027] Figure 11 A partial structural schematic diagram of a battery according to an embodiment of the present invention is shown;

[0028] Figure 12 A partial structural schematic diagram of a battery according to an embodiment of the present invention is shown;

[0029] Figure 13 A schematic diagram of the battery structure according to an embodiment of the present invention is shown;

[0030] Figure 14 A perspective view of a battery according to an embodiment of the present invention is shown.

[0031] The above figures include the following reference numerals:

[0032] 10. Housing; 20. Bare cell; 30. Pressure relief structure; 40. Base plate assembly; 41. Base plate; 42. Elastic element; 43. Base plate; 50. Exhaust channel; 60. Insulating film; 61. First wrapping layer; 62. Second wrapping layer; 63. First through hole; 64. Second through hole; 70. Positive electrode cover plate; 80. Negative electrode cover plate. Detailed Implementation

[0033] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] See also Figures 1 to 14 As shown, this utility model provides a battery, which includes: a housing 10 having a mounting cavity, and a pressure relief structure 30 provided on the bottom wall of the housing 10; a bare battery cell 20 located in the mounting cavity; and a bottom support plate assembly 40 including a bottom support plate 41 installed in the mounting cavity and an elastic support structure. The bottom support plate 41 is disposed at the bottom of the mounting cavity and can support the bare battery cell 20. The elastic support structure is elastically supported between the bottom wall of the housing 10 and the bottom support plate 41, so that the bottom support plate 41 can move relative to the housing 10 in a first direction. An exhaust channel 50 for airflow is formed between the bottom support plate 41 and the bottom wall of the housing 10.

[0035] In this embodiment, the housing 10 has a mounting cavity, in which the bare battery cell 20 is installed. A pressure relief structure 30 is provided on the bottom wall of the housing 10. When the pressure or temperature inside the mounting cavity reaches a threshold, the pressure relief structure 30 enables communication between the mounting cavity and the outside of the housing 10 to relieve pressure. A bottom support plate 41 is located at the bottom of the mounting cavity to support the bare battery cell 20. An exhaust channel 50 for airflow is formed between the bottom support plate 41 and the bottom wall of the housing 10. Gas generated during thermal runaway of the battery can flow smoothly through the exhaust channel 50 to the pressure relief structure 30 and be discharged outside the housing 10 via the pressure relief structure 30.

[0036] The elastic support structure is elastically supported between the bottom wall of the housing 10 and the bottom support plate 41. The bare battery cell 20 is placed on the bottom support plate 41. At this time, the weight of the bare battery cell 20 can compress the elastic support structure. When the battery experiences thermal runaway, a large amount of gas and vapor generated by electrolyte evaporation will be released. The gas flows through the exhaust channel 50 to the pressure relief structure 30 and is discharged from the housing 10 through the pressure relief structure 30. As the gas is released, the weight of the bare battery cell 20 gradually decreases. Under the action of the elastic restoring force of the elastic support structure, the bottom support plate 41 can move away from the bottom wall of the housing 10 along the first direction. At this time, the distance between the bottom support plate 41 and the bottom wall of the housing 10 increases, and the exhaust channel 50 becomes larger, which can accelerate the rate at which the gas in the mounting cavity is discharged from the housing 10. At the same time, the gas generated by thermal runaway continuously flows to the exhaust channel and gradually accumulates upward, which will compress the elastic support structure. At this time, the elastic support structure can also slow down the pressure rise and prevent the housing from rupturing.

[0037] In one embodiment, the pressure relief structure 30 is an explosion-proof valve. When the gas pressure reaches the valve opening pressure, the explosion-proof valve opens, and the elastic support structure elastically recovers its original state. At this time, gas and heat can be discharged, improving the safety of thermal runaway.

[0038] See also Figures 1 to 14 As shown, in one embodiment of the present invention, the elastic support structure includes an elastic element 42, which elastically abuts against the bottom wall of the housing 10 and the bottom support plate 41, and the elastic element 42 is located on the outer periphery of the pressure relief structure 30.

[0039] In this embodiment, the elastic element 42 is disposed in the area of ​​the bottom wall of the housing 10 where the pressure relief structure 30 is not provided, to avoid obstructing the pressure relief structure 30 and affecting the gas discharge. The elastic element 42 elastically abuts against the bottom wall of the housing 10 and the bottom support plate 41. The bare battery cell 20 is placed on the bottom support plate 41. At this time, the weight of the bare battery cell 20 can compress the elastic element 42. When the battery experiences thermal runaway, a large amount of gas and vapor generated by electrolyte evaporation will be released. The gas flows to the pressure relief structure 30 through the exhaust channel 50 and is discharged outside the housing 10 through the pressure relief structure 30. As the gas is released, the weight of the bare battery cell 20 gradually decreases. Under the action of the elastic restoring force of the elastic element 42, the bottom support plate 41 can move away from the bottom wall of the housing 10 along the first direction. At this time, the distance between the bottom support plate 41 and the bottom wall of the housing 10 increases, the exhaust channel 50 becomes larger, and the rate at which the gas in the mounting cavity is discharged outside the housing 10 can be accelerated.

[0040] See also Figures 1 to 14 As shown, in one embodiment of the present invention, the base plate 41 extends along the second direction, and there are at least two elastic members 42. The at least two elastic members 42 are spaced apart along the second direction. The base plate assembly 40 also includes at least two base plates 43. The at least two elastic members 42 are arranged in a one-to-one correspondence with the at least two base plates 43. The elastic members 42 elastically abut against the base plate 41 and the corresponding base plate 43.

[0041] In this embodiment, there are at least two elastic elements 42, which can ensure the stability of the support for the bare battery cell 20. The base plate 43 is attached to the bottom wall of the housing 10. The base plate 43 can not only support the elastic elements 42, but also improve the structural strength of the bottom wall of the housing 10.

[0042] In one embodiment of this utility model, the elastic element 42 is a spring or a sheet.

[0043] In this embodiment, the elastic element 42 is a spring or a sheet. Both the spring and the sheet can drive the bottom plate 41 to move away from the bottom wall of the housing 10 along the first direction when the battery is thermally runaway, thereby increasing the exhaust channel 50 and improving the exhaust rate. At the same time, both the spring and the sheet can provide a certain buffering effect when the battery is subjected to external impact or vibration, protecting the bare cell 20 from damage.

[0044] It should be noted that the shrapnel can be made using existing technology, and the specific structure will not be described in detail here.

[0045] See also Figures 1 to 14 As shown, in one embodiment of the present invention, the elastic element 42 is a spring, and the bottom support plate assembly 40 also includes a guide post. The guide post is fixedly disposed on the bottom support plate 41 or on the bottom wall of the housing 10. The spring is sleeved on the outer periphery of the guide post, and the length of the guide post is less than the minimum distance between the bottom support plate 41 and the bottom wall.

[0046] In this embodiment, the guide post guides the spring in the first direction, preventing the spring from deflecting during extension and retraction, thereby ensuring the smoothness and accuracy of the movement of the base plate 41. The length of the guide post is less than the minimum distance between the base plate 41 and the bottom wall of the housing 10, preventing the guide post from restricting the movement of the base plate 41.

[0047] See also Figures 1 to 14 As shown, in one embodiment of the present invention, the elastic element 42 is a spring, and the bottom support plate assembly 40 also includes a guide post. The guide post is fixedly disposed on the bottom support plate 41 or the bottom plate 43, and the spring is sleeved on the outer periphery of the guide post. The length of the guide post is less than the minimum distance between the bottom support plate 41 and the bottom plate 43.

[0048] In this embodiment, the guide post guides the spring in the first direction, preventing the spring from deflecting during extension and retraction, thereby ensuring the smoothness and accuracy of the movement of the base plate 41. The length of the guide post is less than the minimum distance between the base plate 41 and the bottom wall of the housing 10, preventing the guide post from restricting the movement of the base plate 41.

[0049] See also Figures 1 to 14 As shown, in one embodiment of the present invention, the battery further includes an insulating film 60. The insulating film 60 includes a first covering section and a second covering section connected to each other. The first covering section is longitudinally wrapped around the outer periphery of the bare cell 20. The first covering section covers the bottom surface, top surface and two large surfaces of the bare cell 20 and forms a first wrapping layer 61. The second covering section covers the bottom support plate assembly 40 and at least part of the first wrapping layer 61 and forms a second wrapping layer 62, so that the bottom support plate assembly 40 is located between part of the first wrapping layer 61 and the second wrapping layer 62.

[0050] In this embodiment, the bare cell 20 is a square cell. The large surfaces of the square cell refer to its two largest side surfaces in the length and width directions. These two surfaces are usually the surfaces that contact each other when the bare cells 20 are stacked inside the battery pack. By longitudinally wrapping the first covering section around the outer periphery of the bare cell 20, covering the bottom surface, top surface, and two large surfaces of the bare cell 20, electrical isolation between the bare cell 20 and the outside world can be achieved. The second covering section covers a portion of the bottom support plate assembly 40 and the first wrapping layer 61, forming a second wrapping layer 62. This allows the bottom support plate assembly 40 to be placed between a portion of the first wrapping layer 61 and the second wrapping layer 62, achieving electrical isolation between the bottom support plate assembly 40 and the housing 10. At the same time, it also enables the installation and positioning of the bottom support plate assembly 40.

[0051] See also Figures 1 to 14 As shown, in one embodiment of the present invention, a first through hole 63 is provided on the second covering section, and the first through hole 63 is correspondingly provided with the pressure relief structure 30.

[0052] In this embodiment, the first through hole 63 can reduce the resistance of gas flow to the pressure relief structure 30 and ensure the gas discharge rate.

[0053] In one embodiment of this utility model, the first covering section is connected to the bottom support plate 41.

[0054] In this embodiment, the connection between the first covering section and the bottom support plate 41 simplifies the packaging process and improves production efficiency and packaging quality. When the bare battery cell 20 is covered by the first covering section connected to the bottom support plate 41, the portion of the first covering section containing the bottom support plate 41 must be located between the bottom of the bare battery cell 20 and the bottom wall of the housing 10.

[0055] The first covering section can be connected to the base plate 41 by heat sealing, that is, by using a heating tool to heat the part of the first covering section that is in contact with the base plate 41 to a molten state, and then cooling and solidifying to form a firm connection.

[0056] See also Figures 1 to 14 As shown, in one embodiment of the present invention, a second through hole 64 is provided on the first covering section, and the second through hole 64 is provided corresponding to the top surface of the bare battery cell 20.

[0057] In this embodiment, the second through hole 64 can reduce the resistance to gas flowing out of the bare cell 20 and ensure the gas discharge rate.

[0058] In one embodiment, both the base plate 41 and the base plate 43 can be made of metal or plastic.

[0059] In one embodiment, the elastic element 42 is a spring, which is made of nickel-plated spring steel or elastic rubber (such as fluororubber).

[0060] In one embodiment, the elastic element 42 is a spring with a diameter of 5 mm.

[0061] It should be noted that the diameter of the spring can be set according to the size of the base plate 43.

[0062] In one embodiment, both the base plate 41 and the base plate 43 are made of metal materials (e.g., aluminum, steel, etc.), and the elastic element 42 is a spring. The spring can be fixed to the base plate 43 and the base plate 41 by welding.

[0063] In one embodiment, both the base plate 41 and the base plate 43 are made of plastic, and the elastic element 42 is a spring. The spring can be fixed to the base plate 43 and the base plate 41 by adhesive.

[0064] In one embodiment, the insulating film 60 is a Mylar film or a polyester film.

[0065] See also Figures 1 to 14As shown, in one embodiment of the present invention, the battery further includes a positive electrode cover plate 70 and a negative electrode cover plate 80. The bare cell 20 has a positive electrode tab and a negative electrode tab. The positive electrode tab is welded to the positive electrode cover plate 70, and the negative electrode tab is welded to the negative electrode cover plate 80.

[0066] After welding the negative electrode tab to the negative electrode cover plate 80, an insulating film 60 is wrapped around the bare cell 20, and the ends are sealed with tape, thus forming a whole unit consisting of the bare cell 20, the base plate assembly 40, and the insulating film 60. This unit is then installed into the mounting cavity. Finally, the positive electrode tab is welded to the positive electrode cover plate 70. After liquefaction formation, sealing nails are welded and the film is applied, completing the finished cell. After actual packaging, the pressure relief structure (e.g., an explosion-proof valve) faces downwards.

[0067] According to another aspect of the present invention, a battery pack is provided, comprising: a plurality of batteries as described above.

[0068] In this embodiment, the battery pack has all the technical solutions and effects of the above-mentioned batteries, which will not be repeated here.

[0069] From the above description, it can be seen that the above embodiments of this utility model achieve the following technical effects: A housing, a bare battery cell, and a bottom support plate assembly are provided. The bottom support plate assembly includes a bottom support plate installed in the mounting cavity and an elastic support structure. The bottom support plate is located at the bottom of the mounting cavity and can support the bare battery cell. The elastic support structure is elastically supported between the bottom wall of the housing and the bottom support plate. The bare battery cell is placed on the bottom support plate. At this time, the weight of the bare battery cell can compress the elastic support structure. When the battery experiences thermal runaway, a large amount of gas and vapor generated by electrolyte evaporation will be released. The gas flows through the exhaust channel to the pressure relief structure and is discharged outside the housing through the pressure relief structure. As the gas is released, the weight of the bare battery cell gradually decreases. Under the action of the elastic restoring force of the elastic support structure, the bottom support plate can move away from the bottom wall of the housing along the first direction. At this time, the distance between the bottom support plate and the bottom wall of the housing increases, the exhaust channel becomes larger, and the rate at which the gas in the mounting cavity is discharged outside the housing is accelerated.

[0070] Obviously, the embodiments described above are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0071] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0072] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A battery, characterized in that, include: The housing (10) has a mounting cavity, and the bottom wall of the housing (10) is provided with a pressure relief structure (30). The bare battery cell (20) is located inside the mounting cavity; The base plate assembly (40) includes a base plate (41) installed in the mounting cavity and an elastic support structure. The base plate (41) is disposed at the bottom of the mounting cavity and can support the bare battery cell (20). The elastic support structure is elastically supported between the bottom wall of the housing (10) and the base plate (41) so that the base plate (41) can move relative to the housing (10) in a first direction. An exhaust channel (50) for airflow is formed between the base plate (41) and the bottom wall of the housing (10).

2. The battery according to claim 1, characterized in that, The elastic support structure includes an elastic element (42), which elastically abuts between the bottom wall of the housing (10) and the bottom support plate (41), and the elastic element (42) is located on the outer periphery of the pressure relief structure (30).

3. The battery according to claim 2, characterized in that, The base plate (41) extends along the second direction, and there are at least two elastic elements (42). The at least two elastic elements (42) are spaced apart along the second direction. The base plate assembly (40) also includes at least two base plates (43). The at least two elastic elements (42) and the at least two base plates (43) are arranged in a one-to-one correspondence. The elastic elements (42) elastically abut against the base plate (41) and the corresponding base plate (43).

4. The battery according to claim 2 or 3, characterized in that, The elastic element (42) is a spring or a sheet.

5. The battery according to claim 2, characterized in that, The elastic element (42) is a spring, and the bottom support plate assembly (40) also includes a guide post. The guide post is fixedly installed on the bottom support plate (41) or on the bottom wall of the housing (10). The spring is sleeved on the outer periphery of the guide post, and the length of the guide post is less than the minimum distance between the bottom support plate (41) and the bottom wall.

6. The battery according to claim 3, characterized in that, The elastic element (42) is a spring, and the bottom support plate assembly (40) also includes a guide post. The guide post is fixedly installed on the bottom support plate (41) or the bottom plate (43). The spring is sleeved on the outer periphery of the guide post. The length of the guide post is less than the minimum distance between the bottom support plate (41) and the bottom plate (43).

7. The battery according to any one of claims 1 to 3, characterized in that, The battery also includes an insulating film (60), which includes a first covering section and a second covering section connected to each other. The first covering section is longitudinally wrapped around the outer periphery of the bare cell (20). The first covering section covers the bottom surface, top surface and two large surfaces of the bare cell (20) and forms a first wrapping layer (61). The second covering section covers the bottom plate assembly (40) and at least part of the first wrapping layer (61) and forms a second wrapping layer (62), so that the bottom plate assembly (40) is located between part of the first wrapping layer (61) and the second wrapping layer (62).

8. The battery according to claim 7, characterized in that, The second covering section is provided with a first through hole (63), which is provided in correspondence with the pressure relief structure (30).

9. The battery according to claim 7, characterized in that, The first covering section is connected to the bottom support plate (41).

10. A battery pack, characterized in that, include: Multiple batteries as described in any one of claims 1 to 9.

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