Cylindrical battery and battery pack

Abstract

The utility model relates to the technical field of batteries, in particular to a cylindrical battery and a battery pack. According to the cylindrical battery, an accommodating cavity is formed in a shell; the top cover assembly is connected with the shell so as to seal the containing cavity. The pole group is arranged in the accommodating cavity; the tab arranged in the accommodating cavity is bent, a first connecting part connected with the top cover assembly is formed at one end of the tab in the length direction along a crease formed by bending, a second connecting part connected with the pole group is formed at the other end of the tab, and the second connecting part is obliquely arranged in the accommodating cavity; the insulation protection piece wraps the second connecting part, the width size of the tab is L0, the size of the insulation protection piece in the width direction of the tab is L1, and (L1-L0) / 2 is larger than or equal to 0.5 mm and smaller than or equal to 5 mm. According to the utility model, the insulation protection of the tabs is realized by arranging the insulation protection piece, so that the short circuit condition caused by the lap joint of the tabs in the assembling and using processes of the battery is avoided, and the safety and the stability of the cylindrical battery are improved.

Description

Technical Field

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

[0002] Lithium-ion batteries are increasingly widely used in consumer electronics, power batteries, and energy storage batteries. Currently, lithium-ion cells are broadly categorized structurally into prismatic cells, cylindrical cells, and pouch cells. Among these, cylindrical cells exhibit excellent mechanical properties, showing stronger resistance to deformation during charging and discharging compared to the other two forms, and their dimensions are easier to standardize. Cylindrical batteries consist of a cylindrical casing, cylindrical electrode arrays, electrolyte, and a top cover assembly. The electrode arrays have tabs that connect to the perforated plate in the top cover assembly. During battery assembly and under external impact, the tabs can easily overlap with the casing, causing a short circuit. This reduces the safety performance of the cylindrical battery and battery pack, affecting battery stability. Utility Model Content

[0003] In view of this, the purpose of this application is to provide a cylindrical battery and battery pack to solve the problem that the insulation performance of the tabs in existing cylindrical batteries cannot be guaranteed, thereby affecting the safety performance and structural stability of the battery, and thus reducing the safety performance and service life of the battery pack.

[0004] The first aspect of this utility model provides a cylindrical battery, comprising:

[0005] The shell has an internal cavity.

[0006] A top cover assembly is connected to the housing to close the receiving cavity;

[0007] The pole group is disposed in the receiving cavity;

[0008] The electrode assembly is provided with a protruding electrode tab. The electrode tab disposed in the receiving cavity is bent. Along the fold formed by the bend, one end of the electrode tab in the length direction is formed as a first connecting part connected to the top cover assembly, and the other end of the electrode tab in the length direction is formed as a second connecting part connected to the electrode assembly. The second connecting part is inclined in the receiving cavity.

[0009] An insulating protective component is provided to cover the second connecting portion. The width dimension of the electrode tab is L0, and the dimension of the insulating protective component in the width direction of the electrode tab is L1, where 0.5mm≤(L1-L0) / 2≤5mm.

[0010] Preferably, the first connecting portion is arranged horizontally in the receiving cavity;

[0011] And / or, the first connecting portion and the second connecting portion are bent at an angle α within the receiving cavity, where 10°≤α≤45°.

[0012] Preferably, the length of the first connecting portion is smaller than the length of the second connecting portion.

[0013] Preferably, the length of the insulating protective member is the same as the length of the second connecting portion, and the second connecting portion is located at the middle position of the insulating protective member in the width direction.

[0014] Preferably, the top cover assembly includes:

[0015] A connector is disposed on the side of the top cover assembly facing the receiving cavity, and the first connecting portion is connected to the connector.

[0016] Preferably, the end of the first connecting portion away from the second connecting portion is welded to the connector to form a first welded portion.

[0017] Preferably, the first welded portion is formed as a strip structure extending along the width direction of the electrode tab.

[0018] Preferably, the connector is formed as a plate structure, and the connector has ventilation holes.

[0019] Preferably, the top cover assembly further includes:

[0020] A pressure relief component is disposed on the side of the connector away from the tab and is welded to the connector to form a second welded part.

[0021] The second aspect of this utility model provides a battery pack, including the cylindrical battery described in any of the above technical solutions.

[0022] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0023] This utility model discloses a cylindrical battery with an internal cavity formed in the casing. A top cover assembly is connected to the casing to seal the cavity. The electrode assembly has protruding tabs, which are bent within the cavity. Along the crease formed by the bend, one end of the tab in the longitudinal direction forms a first connection portion connecting to the top cover assembly, and the other end forms a second connection portion connecting to the electrode assembly. An insulating protective element covers the second connection portion, thus providing insulation protection for the inclined portion of the tab within the cavity. This ensures insulation while preventing the insulating protective element from being too large and affecting the electrode assembly. The tabs bend within the housing cavity, increasing their space occupation and affecting the battery's energy sealing and stability. The tab width is L0, and the insulating protective component's dimension in the tab width direction is L1, with 0.5mm ≤ (L1-L0) / 2 ≤ 5mm. This improves the effectiveness and reliability of the insulating protective component's insulation protection of the tabs, preventing short circuits caused by tab overlap during battery assembly and use. This ensures the tabs' insulation performance, thereby enhancing the safety and stability of the cylindrical battery and ultimately extending the battery pack's safety performance and lifespan to meet usage requirements.

[0024] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 A cross-sectional view of the assembly structure of the cylindrical battery with the tabs before the top cover assembly and the housing are assembled, as provided in this embodiment of the utility model.

[0027] Figure 2 for Figure 1 Enlarged structural diagram at point A;

[0028] Figure 3 This is a cross-sectional view of the structure of the cylindrical battery after the top cover assembly and the housing are assembled, provided in an embodiment of the present invention.

[0029] Figure 4 for Figure 3 A magnified structural diagram at point B in the middle.

[0030] Icons: 10-Housing; 11-Receiving cavity; 20-Top cover assembly; 21-Connector; 211-Ventilation hole; 22-Pressure relief component; 201-First welded part; 202-Second welded part; 30-Pole group; 31-Pole tab; 32-Fold; 301-First connecting part; 302-Second connecting part; 40-Insulation protection component. Detailed Implementation

[0031] The following detailed embodiments are provided to help the reader gain a comprehensive understanding of the methods, apparatus, and / or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and / or systems described herein will be apparent after understanding the disclosure of this application. For example, the order of operations described herein is merely illustrative and is not limited to the order set forth herein; changes that will be apparent after understanding the disclosure of this application are possible, except for operations that must occur in a specific order. Furthermore, for clarity and brevity, descriptions of features known in the art may be omitted.

[0032] The features described herein may be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided merely to illustrate some of the many feasible ways of implementing the methods, apparatus, and / or systems described herein that will be apparent upon understanding the disclosure of this application.

[0033] Throughout the specification, when an element (such as a layer, region, or substrate) is described as being "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, it may be directly "on" another element, "connected to" another element, "bonded to" another element, "on" another element, or "covering" another element, or there may be one or more other elements in between. In contrast, when an element is described as being "directly on" another element, "directly connected to" another element, "directly bonded to" another element, "directly on" another element, or "directly covering" another element, there may be no other elements in between.

[0034] As used herein, the term “and / or” includes any one of the relevant items listed and any combination of any two or more items.

[0035] Although terms such as “first,” “second,” and “third” may be used herein to describe individual components, assemblies, regions, layers, or parts, these components, assemblies, regions, layers, or parts are not limited by these terms. Rather, these terms are used only to distinguish one component, assembly, region, layer, or part from another. Therefore, without departing from the teachings of the examples described herein, the first component, assembly, region, layer, or part referred to as the second component, assembly, region, layer, or part may also be referred to as the second component, assembly, region, layer, or part.

[0036] For ease of description, spatial relation terms such as “above,” “upper,” “below,” and “lower” are used herein to describe the relationship between one element and another, as shown in the accompanying drawings. Such spatial relation terms are intended to include not only the orientation depicted in the drawings but also different orientations of the device during use or operation. For example, if the device in the drawings is flipped, an element described as being “above” or “upper” relative to another element will subsequently be “below” or “lower” relative to that 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 relation terms used herein will be interpreted accordingly.

[0037] The terminology used herein is for the purpose of describing various examples only and is not intended to limit this disclosure. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms “comprising,” “including,” and “having” enumerate the stated features, quantities, operations, components, elements, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements, and / or combinations thereof.

[0038] Variations in the shapes shown in the accompanying 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 accompanying drawings, but include changes in shape that may occur during manufacturing.

[0039] The features of the examples described herein can be combined in various ways that will be apparent upon understanding the disclosure of this application. Furthermore, although the examples described herein have a wide variety of constructions, other constructions are possible, as will be apparent upon understanding the disclosure of this application.

[0040] According to a first aspect of the present invention, a cylindrical battery is provided, comprising a housing 10, a top cover assembly 20, an electrode assembly 30, and an insulating protective element 40.

[0041] The specific structure of the cylindrical battery according to this embodiment, as described above, will be described below.

[0042] In this embodiment, as Figure 1 and Figure 3 As shown, a receiving cavity 11 is formed inside the housing 10. The shape of the receiving cavity 11 is the same as the shape of the housing 10. In this embodiment, the outer wall of the housing 10 is cylindrical.

[0043] In this embodiment, as Figure 3 and Figure 4 As shown, the electrode assembly 30 is disposed in the receiving cavity 11, and the electrode assembly 30 may be formed by winding positive and negative electrode sheets; the top cover assembly 20 is connected to the housing 10 to close the receiving cavity 11, and at least part of the top cover assembly 20 is embedded in the receiving cavity 11.

[0044] In this embodiment, as Figures 1 to 4 As shown, the electrode assembly 30 is provided with a protruding tab 31. In this embodiment, the tab 31 protrudes outward from one end of the electrode assembly 30 along its axial direction. The tab 31 and the electrode assembly 30 are assembled together in the receiving cavity 11. The tab 31 disposed in the receiving cavity 11 is bent. Along the crease 32 formed by the bend, the tab 31 is divided into two parts in its length direction. Specifically, one end of the tab 31 in the length direction forms a first connecting part 301 that connects to the top cover assembly 20, and the other end of the tab 31 in the length direction forms a second connecting part 302 that connects to the electrode assembly 30. The first connecting part 301 and the second connecting part 302 are separated by the crease 32. Along the axial direction of the battery, the electrode assembly 30 and the top cover assembly 20 are spaced apart within the receiving cavity 11 to form an installation space within the receiving cavity 11. The second connecting portion 302 is inclined within the receiving cavity 11, that is, the second connecting portion 302 is inclined within the installation space as described above. The insulating protective member 40 covers the second connecting portion 302, thus providing insulating protection for the portion of the tab 31 that is inclined within the receiving cavity 11. This ensures the insulation effect of the tab 31 while also preventing the insulating protective member 40 from being too long, which could affect the bending of the tab 31 within the receiving cavity 11, thereby increasing the space occupied by the tab 31 within the receiving cavity 11 and affecting the energy sealing and stability of the battery.

[0045] In this embodiment, the tab 31 is formed as a sheet structure, and the insulating protective member 40 is disposed on both sides of the second connecting portion 302. The insulating protective member 40 can be an adhesive insulating film or insulating glue to adhere to both sides of the second connecting portion 302. It should be noted that the length direction of the insulating protective member 40 is the same as the length direction of the tab 31, that is... Figure 1 and Figure 2 From a vertical perspective, the width of the tab 31 and the insulating protective element 40 is... Figure 1 and Figure 2The horizontal direction from the perspective of view.

[0046] In a preferred embodiment, such as Figure 1 and Figure 2 As shown, the length of the insulating protective member 40 is the same as the length of the second connecting part 302, thereby completely covering the second connecting part 302 and preventing the second connecting part 302 from being exposed in the installation space as described above, thus improving the insulation protection effect on the tab 31. The second connecting part 302 is located at the middle position of the insulating protective member 40 in the width direction, so that the width of the insulating protective member 40 on both sides of the second connecting part 302 in the width direction is the same, thereby improving the insulation protection effect of the insulating protective member 40 on the tab 31.

[0047] In this embodiment, as Figure 3 and Figure 4 As shown, the crease 32 formed by the bending of the tab 31 is spaced apart from the housing 10 to avoid short circuit caused by contact between the first connecting part 301 and the housing 10, and also to avoid the tab 31 being squeezed when the top cover assembly 20 is assembled with the housing 10.

[0048] In this embodiment, as Figure 2 As shown, the width dimension of the tab 31 is L0, and the dimension of the insulating protective component 40 in the width direction of the tab 31 is L1, 0.5mm≤(L1-L0) / 2≤5mm, thereby improving the effectiveness and reliability of the insulating protective component 40 in insulating the tab 31, so that short circuits will not occur due to the tab 31 overlapping during battery assembly and use, ensuring the insulation performance of the tab 31, thereby improving the safety and stability of the cylindrical battery, and thus ensuring that the service life of the battery pack meets the usage requirements.

[0049] Preferably, in this embodiment, the first connecting part 301 is arranged horizontally in the receiving cavity 11. Specifically, the first connecting part 301 is arranged parallel to the connecting member 21 described below.

[0050] In this embodiment, as Figure 4 As shown, the first connecting part 301 and the second connecting part 302 are bent at an angle α in the receiving cavity 11, where 10°≤α≤45°. This ensures that the tab 31 has sufficient bending and assembly requirements in the receiving cavity 11, and also avoids that the distance between the electrode group 30 and the top cover assembly 20 is too large, which would reduce the space occupied by the electrode group 30 in the receiving cavity 11 and affect the energy density of the battery.

[0051] In this embodiment, as Figure 1 and Figure 3As shown, the length of the first connecting part 301 is smaller than the length of the second connecting part 302. The dimensions of the first connecting part 301 and the second connecting part 302 in the width direction of the tab 31 are the same, that is, the dimensions of the first connecting part 301 and the second connecting part 302 in the width direction of the tab 31 are both L0. This satisfies the assembly requirements of the first connecting part 301 and the top cover assembly 20, while also facilitating the bending of the tab 31 in the receiving cavity 11. It also allows the tab 31 to have a larger area that can be covered by the insulating protective component 40, thereby improving the insulation and protection effect of the tab 31.

[0052] Furthermore, in this embodiment, such as Figures 1 to 4 As shown, the top cover assembly 20 includes a connector 21 disposed on the side of the top cover assembly 20 facing the receiving cavity 11. The connector 21 is formed into a plate-like structure. The first connecting part 301 is connected to the connector 21, thereby realizing the connection between the tab 31 and the top cover assembly 20.

[0053] Furthermore, in this embodiment, as Figure 1 and Figure 2 As shown, the end of the first connecting part 301 away from the second connecting part 302 is welded to the connector 21 to form the first welding part 201. In this way, the electrode 31 and the connector 21 are firmly connected by welding. The welding method can be laser welding.

[0054] Furthermore, such as Figure 1 and Figure 2 As shown, the first welding part 201 is formed as a strip structure extending along the width direction of the tab 31, thereby increasing the connection area between the first connecting part 301 and the connector 21 without affecting the bending of the tab 31, and ensuring reliable connection.

[0055] Preferably, the first welding part 201 of the strip structure is provided in multiple ways, and the multiple first welding parts 201 are arranged at intervals along the length direction of the first connecting part 301. This improves the connection strength while avoiding the welding process from affecting the shape accuracy of the connecting part 21.

[0056] In this embodiment, as Figure 1 and Figure 2 As shown, the connector 21 has a vent hole 211, which is a through hole structure that penetrates the thickness direction of the connector 21. When the battery experiences thermal runaway and internal gas generation occurs, the gas can flow out towards the outside of the battery through the vent hole 211. Preferably, multiple vent holes 211 are provided, and the multiple vent holes 211 are arranged in a ring and spaced apart from each other.

[0057] Furthermore, in this embodiment, such as Figures 1 to 4As shown, the top cover assembly 20 also includes a pressure relief component 22, which can be an explosion-proof sheet or an explosion-proof valve, etc. The pressure relief component 22 is provided with grooves. When the battery thermal runaway causes the pressure in the receiving cavity 11 to reach the opening pressure, the pressure relief component 22 bursts along the crack, so that the inside and outside of the battery are connected, thereby realizing the venting and pressure relief to ensure the safety performance of the battery.

[0058] Specifically, the pressure relief component 22 is formed as a plate structure and is located on the side of the connector 21 away from the tab 31. The pressure relief component 22 is welded to the connector 21 to form a second welded portion 202. Gas inside the battery can pass through the vent hole 211 and act on the pressure relief component 22 to push it outward, thus separating the pressure relief component 22 from the connector 21, thereby providing power-off protection. In this embodiment, the second welded portion 202 is located in the middle of the connector 21, and the first welded portion 201 is located radially between the second welded portion 202 and the vent hole 211. It should be noted that the radial direction of the battery is... Figure 3 and Figure 4 The horizontal direction from the perspective of the battery's axis is the same as the horizontal direction. Figure 3 and Figure 4 The vertical direction from the perspective of view.

[0059] According to the present invention, a cylindrical battery has an internal cavity formed in the casing; a top cover assembly is connected to the casing to seal the cavity; protruding tabs are provided on the electrode assembly, and the tabs disposed in the cavity are bent. Along the fold formed by the bend, one end of the tab in the length direction forms a first connection portion connecting to the top cover assembly, and the other end of the tab in the length direction forms a second connection portion connecting to the electrode assembly. An insulating protective member covers the second connection portion, thus providing insulating protection for the inclined portion of the tab in the cavity, ensuring insulation while preventing leakage. Excessive length of the insulation protection component affects the bending of the tabs within the housing cavity, increasing the space occupied by the tabs and impacting the battery's energy sealing and stability. The tab width is L0, and the insulation protection component's dimension in the tab width direction is L1, with 0.5mm ≤ (L1-L0) / 2 ≤ 5mm. This improves the effectiveness and reliability of the insulation protection component's insulation protection of the tabs, preventing short circuits caused by tab overlap during battery assembly and use, ensuring the tabs' insulation performance, and thus enhancing the safety and stability of the cylindrical battery.

[0060] According to the present invention, a battery pack includes cylindrical batteries as described above. Multiple cylindrical batteries are arranged in series and / or in parallel within the housing of the battery pack. The insulation performance of the tabs of each cylindrical battery is guaranteed, thereby reducing the risk of short circuits and leakage of the cylindrical batteries, and thus improving the safety performance and service life of the battery pack.

[0061] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The protection scope of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the technical scope disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the protection scope of this application. Therefore, the protection scope of this application should be determined by the protection scope of the claims.

Claims

1. A cylindrical battery, characterized in that, include: The shell has an internal cavity. A top cover assembly is connected to the housing to close the receiving cavity; The pole group is disposed in the receiving cavity; The electrode assembly is provided with a protruding electrode tab. The electrode tab disposed in the receiving cavity is bent. Along the fold formed by the bend, one end of the electrode tab in the length direction is formed as a first connecting part connected to the top cover assembly, and the other end of the electrode tab in the length direction is formed as a second connecting part connected to the electrode assembly. The second connecting part is inclined in the receiving cavity. An insulating protective component is provided to cover the second connecting portion. The width dimension of the electrode tab is L0, and the dimension of the insulating protective component in the width direction of the electrode tab is L1, where 0.5mm≤(L1-L0) / 2≤5mm.

2. The cylindrical battery according to claim 1, characterized in that, The first connecting portion is arranged horizontally in the receiving cavity; And / or, the first connecting portion and the second connecting portion are bent at an angle α within the receiving cavity, where 10°≤α≤45°.

3. The cylindrical battery according to claim 1, characterized in that, The length of the first connecting part is smaller than that of the second connecting part, and the first connecting part and the second connecting part have the same dimensions in the tab width direction.

4. The cylindrical battery according to claim 1, characterized in that, The length of the insulating protective component is the same as the length of the second connecting portion, and the second connecting portion is located at the middle position of the insulating protective component in the width direction.

5. The cylindrical battery according to claim 1, characterized in that, The top cover assembly includes: A connector is disposed on the side of the top cover assembly facing the receiving cavity, and the first connecting portion is connected to the connector.

6. The cylindrical battery according to claim 5, characterized in that, The end of the first connecting portion away from the second connecting portion is welded to the connector to form a first welded portion.

7. The cylindrical battery according to claim 6, characterized in that, The first welded portion is formed as a strip structure extending along the width direction of the electrode tab.

8. The cylindrical battery according to claim 5, characterized in that, The connector is formed into a plate-like structure, and the connector has ventilation holes.

9. The cylindrical battery according to claim 5, characterized in that, The top cover assembly also includes: A pressure relief component is disposed on the side of the connector away from the tab and is welded to the connector to form a second welded part.

10. A battery pack, characterized in that, Includes the cylindrical battery as described in any one of claims 1 to 9.

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