Battery cell structure and battery pack

Abstract

The utility model provides a battery cell structure and a battery pack. The battery cell structure further comprises an anti-explosion valve, a supporting plate and a fusing plate; the supporting plate is arranged between the shell and the naked battery cell; the fusing plate is arranged on the supporting plate, and the explosion-proof valve is arranged on the shell corresponding to the fusing plate; when the temperature in the shell reaches a first preset temperature, the fusing plate is fused; when the temperature in the shell is larger than the first preset temperature, the anti-explosion valve is opened. The explosion-proof valve is arranged on the shell instead of the cover plate, so that the distance between the explosion-proof valve and the pole group is smaller than the distance between an existing explosion-proof valve and the pole group, that is, the distance between the pole group and the explosion-proof valve is shortened, and then gas can be quickly discharged out of the shell in a short path; the explosion-proof valve is arranged on the shell and is not on the same side with the pole group on the cover plate assembly, so that the direction of exhaust through the explosion-proof valve and the pole column are on the different side, gas-electricity separation is realized, and gas sprayed out of the explosion-proof valve is prevented from interfering with electric connection between the pole column and other equipment.

Description

Technical Field

[0001] The present application relates to the technical field of lithium-ion power batteries, and in particular to a battery cell structure and a battery pack. Background Art

[0002] As lithium-ion battery technology becomes increasingly mature, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields, and the requirements for the performance and safety of lithium-ion batteries are increasing.

[0003] The cell structure is the core component of battery pack safety and assembly, and its structural design is crucial to battery pack safety. Existing cell structures mostly use a cover plate explosion-proof valve structure. This structure has the following defects:

[0004] (1) Since most thermal runaway is caused by the pole group, and since the distance from the pole group to the explosion-proof valve on the cover plate is long, the gas and heat generated by the thermal runaway cannot be discharged immediately.

[0005] (2) Since the explosion-proof valve and the pole are located on the same side, the high-temperature gas, flame, electrolyte particles, etc. ejected from the explosion-proof valve will interfere with the connection between the pole and external electrical equipment.

[0006] Therefore, there is an urgent need for a battery cell structure and a battery pack to solve the technical problems existing in the prior art to a certain extent. Utility Model Content

[0007] The purpose of the present application is to provide a battery cell structure and a battery pack, which can shorten the distance from the pole group to the explosion-proof valve to a certain extent, thereby enabling the gas to be discharged from the shell through a shorter path. In addition, the direction in which the gas is discharged through the explosion-proof valve is on the opposite side of the pole, thereby ensuring the safety of the electrical connection between the pole and other equipment.

[0008] The present application provides a battery cell structure; comprising a shell, a bare battery cell and a cover plate assembly, wherein the bare battery cell is arranged in the shell, and the cover plate assembly is respectively arranged at both ends of the shell along the length direction thereof to seal the bare battery cell in the shell; the battery cell structure also includes an explosion-proof valve, a support plate and a fuse plate;

[0009] The support plate is arranged between the shell and the bare battery core;

[0010] The fuse plate is arranged on the support plate, and the explosion-proof valve is arranged on the housing at a position corresponding to the fuse plate;

[0011] When the temperature in the shell reaches a first preset temperature, the fuse plate melts; when the temperature in the shell reaches a second preset temperature greater than the first preset temperature, the explosion-proof valve opens.

[0012] In the above technical solution, further, a protrusion is provided on a side of the support plate away from the bare battery cell;

[0013] The protrusions are respectively arranged at two ends of the support plate along the width direction and extend along the length direction of the support plate;

[0014] The protrusion supports the support plate away from the shell by a preset distance so that a gap is formed between the support plate and the shell.

[0015] In the above technical solution, further, the support plate and the fuse plate are made of the same material and the thickness of the fuse plate is smaller than the thickness of the support plate.

[0016] In the above technical solution, further, the melting point of the fuse plate is lower than the melting point of the support plate.

[0017] In the above technical solution, further, a first hole is opened on the support plate, and the fuse plate is arranged in the first hole.

[0018] In the above technical solution, further, a second hole is opened on the support plate, and the second hole can conduct the gas generated by the bare battery cell to the explosion-proof valve.

[0019] In the above technical solution, further, a plurality of the second holes are provided, and the plurality of the second holes are arranged in a matrix.

[0020] In the above technical solution, further, the fuse plate is provided with holes, a plurality of the holes are provided, and the plurality of the holes are arranged in a matrix.

[0021] In the above technical solution, further, the explosion-proof valve is arranged on the side wall of the shell formed by the length direction and the thickness direction or the side wall formed by the length direction and the width direction.

[0022] The present application also provides a battery pack, comprising the above-mentioned battery cell structure.

[0023] Compared with the prior art, this application has the following beneficial effects:

[0024] The present application provides a battery cell structure; comprising a shell, a bare battery cell and a cover plate assembly, wherein the bare battery cell is arranged in the shell, and the cover plate assembly is respectively arranged at both ends of the shell along the length direction thereof to seal the bare battery cell in the shell; the battery cell structure also includes an explosion-proof valve, a support plate and a fuse plate;

[0025] The support plate is arranged between the shell and the bare battery core;

[0026] The fuse plate is arranged on the support plate, and the explosion-proof valve is arranged on the housing at a position corresponding to the fuse plate;

[0027] When the temperature in the shell reaches a first preset temperature, the fuse plate melts; when the temperature in the shell reaches a second preset temperature greater than the first preset temperature, the explosion-proof valve opens.

[0028] In summary, the present application provides a battery cell structure in which an explosion-proof valve is arranged on the shell instead of the cover plate, so that the distance between the explosion-proof valve and the pole group is smaller than the distance between the existing explosion-proof valve and the pole group, that is, the distance from the pole group to the explosion-proof valve is shortened, so that the gas can be quickly discharged from the shell through a shorter path; since the explosion-proof valve is arranged on the shell and is not on the same side as the pole group on the cover plate assembly, the exhaust direction through the explosion-proof valve is on the opposite side from the pole, thereby realizing gas-electricity separation, preventing the gas ejected through the explosion-proof valve from interfering with the electrical connection between the pole and other equipment, and ensuring the safety of the electrical connection between the pole and other equipment.

[0029] The present application also provides a battery pack, including the above-mentioned battery cell structure, and thus has all the beneficial effects of the battery cell, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0031] Figure 1 This is a schematic structural diagram of the battery cell structure provided in Example 1 of the present application at a first viewing angle;

[0032] Figure 2 This is a schematic structural diagram of the battery cell structure provided in Example 1 of the present application at a second viewing angle;

[0033] Figure 3 for Figure 2 The enlarged view of point A in the middle;

[0034] Figure 4 This is a schematic structural diagram of a support plate in a battery cell structure provided in Example 1 of the present application;

[0035] Figure 5 This is a schematic diagram of the structure of the support plate and the fuse plate in the battery cell structure provided in Example 1 of the present application.

[0036] Figure numerals: 1-shell; 2-bare cell; 3-cover plate assembly; 4-end plate; 5-explosion-proof valve; 6-support plate; 7-fuse plate; 8-protrusion; 9-gap; 10-first hole; 11-second hole; 12-hole; 13-insulating layer. DETAILED DESCRIPTION

[0037] The following specific embodiments are provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be apparent. For example, the order of operations described herein is merely an example, and is not limited to the order set forth herein, but in addition to the operations that must occur in a particular order, changes that will be apparent after understanding the disclosure of the present application may be made. In addition, in order to improve clarity and brevity, descriptions of features known in the art may be omitted.

[0038] The features described herein may be implemented in different forms and should not be interpreted as being limited to the examples described herein. Rather, the examples described herein have been provided only to illustrate some of the many possible ways of implementing the methods, devices and / or systems described herein that will be apparent after understanding the disclosure of the present application.

[0039] Throughout the specification, when an element (such as a layer, a region, or a substrate) is described as being “on”, “connected to”, “bound to”, “over”, or “covering” another element, it may be directly “on”, “connected to”, “bound to”, “over”, or “covering” another element, or one or more other elements may be present between them. In contrast, when an element is described as being “directly on”, “directly connected to”, “directly bound to”, “directly over”, or “directly covering” another element, there may be no other elements present between them.

[0040] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more items.

[0041] Although terms such as "first," "second," and "third" may be used herein to describe various members, components, regions, layers, or portions, these members, components, regions, layers, or portions are not limited by these terms. Rather, these terms are only used to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Therefore, without departing from the teachings of the examples described herein, the first member, component, region, layer, or portion referred to may also be referred to as the second member, component, region, layer, or portion.

[0042] For ease of description, spatial relational terms such as "above", "upper", "below", and "lower" may be used herein to describe the relationship of one element to another element as shown in the accompanying drawings. Such spatial relational terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. For example, if the device in the accompanying drawings is turned over, an element described as being "above" or "upper" relative to another element will subsequently be "below" or "lower" relative to the other element. Therefore, the term "above" includes both "above" and "below" orientations depending on the spatial orientation of the device. The device may also be positioned in other ways (e.g., rotated 90 degrees or in other orientations), and the spatial relational terms used herein will be interpreted accordingly.

[0043] The terms used herein are only used to describe various examples and are not used to limit the present disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "include", "comprise" and "have" list the stated features, quantities, operations, components, elements and / or their combinations that exist, but do not exclude the existence or addition of one or more other features, quantities, operations, components, elements and / or their combinations.

[0044] Variations in the shapes shown in the drawings may occur due to manufacturing techniques and / or tolerances. Therefore, the examples described herein are not limited to the specific shapes shown in the drawings but include variations in shapes that occur during manufacturing.

[0045] The features of the examples described herein may be combined in various ways that will be apparent after understanding the disclosure of the present application. In addition, although the examples described herein have various configurations, other configurations are possible as will be apparent after understanding the disclosure of the present application.

[0046] Embodiment 1

[0047] Combine the following Figure 1-Figure 5 A battery cell structure provided in the present application is described in detail.

[0048] In this embodiment, a battery cell structure is provided, combining Figure 1As shown, the cell structure includes a shell 1, a bare cell 2 and a cover plate assembly 3; specifically, the shell 1 is a cylindrical structure and is surrounded by an installation space, the bare cell 2 is arranged in the installation space, and further, the bare cell 2 is composed of a plurality of superimposed electrode groups; specifically, the cover plate assembly 3 is respectively arranged at both ends of the shell 1 along its length direction to seal the bare cell 2 to the shell 1; further, the bare cell 2 is connected to the cover plate assembly 3 through the end plate 4; further, the cover plate assembly 3 includes a cover plate, a current collector and a connecting sheet, the current collector is arranged on the side of the cover plate facing the bare cell 2, and the pole ear of the bare cell 2 is welded to the connecting sheet as a whole and then welded to the current collector.

[0049] Specifically, the battery cell structure also includes an explosion-proof valve 5, a support plate 6 and a fuse plate 7; wherein the support plate 6 is arranged between the shell 1 and the bare battery cell 2; the fuse plate 7 is arranged on the support plate 6, and the explosion-proof valve 5 is arranged on the shell 1 at a position corresponding to the fuse plate 7.

[0050] In actual use, when the pole group is in thermal runaway, the pole group will generate a large amount of high-temperature gas. When the temperature in the shell 1 reaches the first preset temperature (the first preset temperature at this time is not the temperature at which the explosion-proof valve 5 opens, but the temperature at which the fuse plate 7 can be melted), the fuse plate 7 melts. When the fuse plate 7 melts, a larger gas guide channel will be formed on the support plate 6, which can quickly guide the high-temperature gas generated by the pole group to the explosion-proof valve 5; in addition, the gas guide channel will not only guide the high-temperature gas, but also guide the electrolyte particles, flames, etc., and the larger gas guide channel will not be blocked by the electrolyte particles; when the gas temperature generated by the thermal runaway of the pole group in the shell 1 is a second preset temperature greater than the first preset temperature, that is, when the temperature reaches the temperature at which the explosion-proof valve 5 opens, the explosion-proof valve 5 opens. The above-mentioned second preset temperature is the opening temperature of the explosion-proof valve; the first preset temperature is preferably 30 degrees, and the second preset temperature is preferably 32°.

[0051] In summary, the present application provides a battery cell structure in which the explosion-proof valve 5 is arranged on the shell 1 instead of the cover plate, so that the distance between the explosion-proof valve 5 and the pole group is smaller than the distance between the existing explosion-proof valve 5 and the pole group, that is, the distance from the pole group to the explosion-proof valve 5 is shortened, so that the gas can be quickly discharged from the shell 1 through a shorter path; since the explosion-proof valve 5 is arranged on the shell 1 and is not on the same side as the pole group on the cover plate assembly 3, the exhaust direction through the explosion-proof valve 5 is on the opposite side from the pole, thereby realizing gas-electricity separation, preventing the gas ejected through the explosion-proof valve 5 from interfering with the electrical connection between the pole and other equipment, and ensuring the safety of the electrical connection between the pole and other equipment.

[0052] In this embodiment, an insulating layer 13 is provided on the outer side of the bare cell, and the support plate is arranged between the insulating layer and the housing.

[0053] In this embodiment, combined with Figure 4As shown, a protrusion 8 is provided on the side of the support plate 6 facing away from the bare battery cell 2, that is, a protrusion 8 is provided on the side of the support plate 6 facing the shell 1; preferably, the support plate 6 is a plate-like structure, and the protrusion 8 is a strip-like structure.

[0054] Specifically, the protrusions 8 are respectively arranged at both ends of the support plate 6 along the width direction and extend along the length direction of the support plate 6, that is, the cross-sections of the support plate 6 and the protrusions 8 are groove-shaped; the protrusions 8 can support the support plate 6 away from the shell 1 at a preset distance so that a gap 9 is formed between the support plate 6 and the shell 1.

[0055] Furthermore, the preset distance here is approximately equal to the thickness of the explosion-proof valve 5 .

[0056] In summary, in the actual installation process, the explosion-proof valve 5 will be slightly concave toward the bare battery cell 2, and the support plate 6 is installed in the shell 1 by inserting it into the shell 1. In order to prevent the support plate 6 from hitting the explosion-proof valve 5 during the insertion process and causing damage to the explosion-proof valve 5, a gap 9 is formed between the support plate 6 and the shell 1 through the setting of the protrusion 8. In other words, since the protrusion 8 supports the support plate 6 away from the shell 1, when the support plate 6 is inserted into the shell 1, the support plate 6 will not hit the explosion-proof valve 5, thereby ensuring the integrity of the explosion-proof valve 5.

[0057] In this embodiment, for the fuse plate 7, the material of the fuse plate 7 can be set to be the same as the material of the support plate 6. In order to ensure that the fuse plate 7 blows first when the temperature inside the shell 1 reaches the first preset temperature, the thickness of the fuse plate 7 is set to be smaller than the thickness of the support plate 6. In this way, when the temperature inside the shell 1 reaches the first preset temperature, the fuse plate 7 will blow first.

[0058] In this embodiment, for the fuse plate 7, the material of the fuse plate 7 can also be set to be different from the material of the support plate 6. Then, in order to ensure that when the temperature in the shell 1 reaches the first preset temperature, the fuse plate 7 melts first, the melting point of the support plate 6 is lower than the melting point of the support plate 6, that is, when the temperature in the shell 1 reaches the first preset temperature, the fuse plate 7 will melt first.

[0059] In this embodiment, combined with Figure 4 As shown, a first hole 10 is opened on the support plate 6 , and the fuse plate 7 is arranged in the first hole 10 ; the long axis of the first hole 10 extends along the length direction of the housing 1 .

[0060] In this embodiment, combined with Figure 4 As shown, a second hole 11 is opened on the support plate 6 , and the second hole 11 can conduct the gas generated by the bare battery cell 2 to the explosion-proof valve 5 .

[0061] Preferably, a plurality of second holes 11 are provided, and the plurality of second holes 11 are arranged in a matrix.

[0062] Preferably, the major axis of the second hole 11 extends along the length direction of the housing 1 .

[0063] In this embodiment, a plurality of holes 12 are provided on the fuse plate 7, and the plurality of holes 12 are arranged in a matrix. When the temperature does not reach the first preset temperature, the hole 12 has the same function as the second hole 11, and both can conduct the gas generated in the housing 1 to the explosion-proof valve 5.

[0064] It is worth noting that there are multiple options for the size of the hole 12 , the size of the first hole 10 , and the size of the second hole 11 , and they can be reasonably set for different battery cells.

[0065] In this embodiment, combined with Figure 1 As shown, the explosion-proof valve 5 is arranged on the side wall of the housing 1 which is formed in the length direction and the thickness direction.

[0066] In addition, side walls consisting of length and width directions can also be set. It is worth noting that if side walls consisting of length and width directions are chosen, the support plate 6 will occupy the space in the shell 1, which will cause the capacity of the bare battery cell 2 to be relatively small. When using this method, the capacity of the bare battery cell 2 needs to be considered.

[0067] Embodiment 2

[0068] The present application also provides a battery pack, including the above-mentioned battery cell structure, and thus has all the beneficial effects of the battery cell structure, which will not be elaborated in detail here.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell structure; comprising a shell, a bare battery cell and a cover plate assembly, wherein the bare battery cell is arranged in the shell, and the cover plate assembly is respectively arranged at both ends of the shell along the length direction thereof to seal the bare battery cell in the shell; characterized in that: The battery core structure also includes an explosion-proof valve, a support plate and a fuse plate; The support plate is arranged between the shell and the bare battery core; The fuse plate is arranged on the support plate, and the explosion-proof valve is arranged on the housing at a position corresponding to the fuse plate; When the temperature in the shell reaches a first preset temperature, the fuse plate melts; when the temperature in the shell reaches a second preset temperature greater than the first preset temperature, the explosion-proof valve opens.

2. The battery cell structure according to claim 1, characterized in that: A protrusion is provided on a side of the support plate away from the bare battery cell; The protrusions are respectively arranged at two ends of the support plate along the width direction and extend along the length direction of the support plate; The protrusion supports the support plate away from the shell by a preset distance so that a gap is formed between the support plate and the shell.

3. The battery cell structure according to claim 1, characterized in that: The support plate is made of the same material as the fuse plate and the fuse plate has a thickness smaller than that of the support plate.

4. The battery cell structure according to claim 1, characterized in that: The melting point of the fuse plate is lower than the melting point of the support plate.

5. The battery cell structure according to claim 1, characterized in that: A first hole is formed on the support plate, and the fuse plate is disposed in the first hole.

6. The battery cell structure according to claim 1, characterized in that: A second hole is formed on the support plate, and the second hole can conduct the gas generated by the bare battery cell to the explosion-proof valve.

7. The battery cell structure according to claim 6, characterized in that: A plurality of the second holes are provided, and the plurality of the second holes are arranged in a matrix.

8. The battery cell structure according to claim 1, characterized in that: The fuse plate is provided with a plurality of holes, and the plurality of holes are arranged in a matrix.

9. The battery core structure according to claim 1, characterized in that: The explosion-proof valve is arranged on a side wall of the housing which is formed by a length direction and a thickness direction or a side wall which is formed by a length direction and a width direction.

10. A battery pack, characterized in that: A battery cell structure comprising any one of claims 1 to 9.

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