A single cell and a battery pack

Abstract

The application provides a single battery and a battery pack, and belongs to the technical field of batteries. The single battery comprises a shell, an electrode assembly, a top cover and a first insulating piece; the top cover is connected with one end of the shell along a first direction, and the top cover has a thinning portion; the electrode assembly is arranged in the shell; an explosion-proof valve is connected with the top cover, the explosion-proof valve is located in the thinning portion, the explosion-proof valve is integrally formed with the top cover, and a weak portion is arranged on the side of the explosion-proof valve away from the electrode assembly. The single battery provided by the application integrally forms the explosion-proof valve on the top cover, reduces the production process of connecting the explosion-proof valve and the top cover, improves the production and processing efficiency of the top cover, reduces the production cost of the top cover, sets the thinning portion on the top cover to reduce the weight and cost of the top cover, provides more space for the single battery in the shell, and effectively improves the energy density of the single battery.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a single cell battery and a battery pack. Background Technology

[0002] In the field of power batteries, as the market demand for driving range continues to increase, major manufacturers are optimizing the structural design of power battery systems to improve system energy density, thereby increasing battery pack capacity and driving range.

[0003] In existing battery top covers, the explosion-proof valve is connected to the top cover by welding, which not only increases the production steps in the battery top cover manufacturing process, but also increases the production cost of the top cover. Utility Model Content

[0004] In view of this, the purpose of this application is to overcome the shortcomings of the prior art and provide a single cell battery and a battery pack.

[0005] This application provides the following technical solution: a single-cell battery, having a first orientation, comprising: case; A top cover is connected to one end of the housing along the first direction, and the top cover includes a thinned portion; Electrode assemblies are disposed within the housing; An explosion-proof valve is connected to the top cover. The explosion-proof valve is located inside the thinned section. The explosion-proof valve and the top cover are integrally formed. The explosion-proof valve has a weak part on the side opposite to the electrode assembly.

[0006] In some embodiments, the single cell further includes a first insulating member disposed within the housing, the first insulating member being connected to the top cover on the side near the electrode assembly; The first insulating member has a first recess on the side facing the top cover. The first recess is recessed towards the side close to the electrode assembly. The top cover also includes a protrusion. The protrusion is connected to the side of the thinned portion facing the electrode assembly and is disposed within the first recess.

[0007] In some embodiments, the protrusion includes a first protrusion surrounding the explosion-proof valve and engaging with the first recess.

[0008] In some embodiments, the weak portion is recessed towards the electrode assembly along the first direction, and the weak portion protrudes towards the electrode assembly along the first direction to form a boss. The first protrusion is disposed around the boss. The first insulating member is provided with a relief groove on the side facing the explosion-proof valve. The relief groove is recessed towards the electrode assembly along the first direction, and the boss is engaged in the relief groove.

[0009] In some embodiments, the single cell has a second direction perpendicular to the first direction; The protrusion includes a second protrusion, and the thinning portion has the second protrusion at both ends along the second direction, with the second protrusion located on the side of the thinning portion facing the electrode assembly; The first insulating member has a second recess on the side facing the thinned portion. The second recess and the first recess are spaced apart along the second direction. The second recess is recessed towards the side of the electrode assembly along the first direction. The second protrusion is engaged with the second recess.

[0010] In some embodiments, the single battery cell further includes a terminal post, a second insulating member, and a riveting portion, wherein the second insulating member is disposed on the side of the top cover opposite to the first insulating member, and the riveting portion is disposed on the side of the second insulating member opposite to the top cover; The end of the electrode post facing away from the electrode assembly along the first direction passes through the first insulating member, the top cover, and the second insulating member. The portion of the electrode post passing through the second insulating member is fixedly connected to the riveting part. The end of the electrode post near the electrode assembly is electrically connected to the electrode assembly.

[0011] In some embodiments, the protrusion includes a third protrusion disposed on the side of the top cover facing the electrode assembly, and the third protrusion is disposed around the electrode post; The first insulating member has a third recess on the side facing the thinned portion, the third recess is recessed towards the electrode assembly, and the third protrusion is engaged in the third recess.

[0012] In some embodiments, the thinned portion is recessed along the first direction on the side facing the first insulating member to the side away from the first insulating member to form a fourth recessed portion; The first insulating member has a fourth protrusion on the side facing the top cover, the fourth protrusion is engaged with the fourth recess, and the third protrusion is arranged around the fourth protrusion.

[0013] In some embodiments, the top cover further includes a flange located at the edge of the thinned portion on the side opposite to the electrode assembly, and the height of the flange along the first direction is greater than the height of the thinned portion along the first direction.

[0014] Secondly, this application provides a battery pack including the aforementioned single battery cell.

[0015] The embodiments of this application have the following advantages: by integrally molding the explosion-proof valve onto the top cover, the stability of the connection between the explosion-proof valve and the top cover is ensured, while the production process of connecting the explosion-proof valve and the top cover is reduced, which not only improves the production efficiency of the top cover, but also reduces the production cost of the top cover; by setting a thinning part on the top cover, the weight and cost of the top cover are reduced, so as to provide more space for the single battery in the casing, thereby effectively improving the energy density of the single battery.

[0016] 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

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This paper shows a schematic diagram of the structure of a single-cell battery from one perspective, based on some embodiments of this application. Figure 2 An exploded view of a single-cell battery provided by some embodiments of this application is shown; Figure 3 An exploded view of a first embodiment of a top cover and a first insulating member in a single-cell battery provided by some embodiments of this application is shown; Figure 4 An exploded view of a second embodiment of a top cover and a first insulating member in a single-cell battery provided by some embodiments of this application is shown; Figure 5 This illustration shows a schematic structural view of a second embodiment of the top cover in a single-cell battery provided by some embodiments of this application; Figure 6 This invention provides a schematic structural view of a second embodiment of the connection between the top cover and the first insulating member in a single-cell battery, according to some embodiments of this application. Figure 7 It shows Figure 6 Sectional view of section AA; Figure 8 It shows Figure 7 Enlarged view of section B; Figure 9 An exploded view of a third embodiment of a single-cell battery and a first insulating member provided in some embodiments of this application is shown; Figure 10 The diagram shows a structural schematic from one perspective of a third embodiment of the top cover in a single-cell battery provided by some embodiments of this application.

[0019] Explanation of key component symbols: 100-Housing; 200-Electrode assembly; 300-Top cover; 310-Thinned portion; 320-Explosion-proof valve; 321-Weak portion; 330-Protrusion; 331-First protrusion; 332-Second protrusion; 333-Third protrusion; 340-Fourth recess; 350-Boss; 360-Flange; 400-First insulating component; 411-First recess; 412-Second recess; 413-Third recess; 414-Fourth protrusion; 420-Groove; 500-Riveting portion; 600-Second insulating component; 700-Electrode post.

[0020] Z - First direction; X - Second direction. Detailed Implementation

[0021] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0022] It should be noted that when an element is said to be "fixed" to another element, it can be directly on the other element or there may be an intervening element. When an element is said to be "connected" to another element, it can be directly connected to the other element or there may be an intervening element. Conversely, when an element is said to be "directly" on another element, there is no intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0023] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the template description is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0026] like Figures 1 to 4 As shown, some embodiments of this application provide a single battery, which mainly integrates the explosion-proof valve 320 onto the top cover 300. This not only ensures the mechanical strength of the top cover 300 but also reduces the production process of connecting the explosion-proof valve 320 and the top cover 300, thereby improving the production efficiency of the top cover 300 and reducing its production cost.

[0027] The single cell includes a casing 100, a top cover 300, an electrode assembly 200, and an explosion-proof valve 320.

[0028] The top cover 300 is connected to one end of the housing 100 along the first direction Z. The connection method between the top cover 300 and the housing 100 includes any one of bonding, welding, or hot-melt connection, which can be specifically set according to the actual situation. The top cover 300 includes a thinned portion 310.

[0029] The electrode assembly 200 is disposed inside the housing 100, so that the housing 100 and the top cover 300 provide protection and limit the electrode assembly 200 to ensure the stability of the electrode assembly 200 inside the housing 100.

[0030] The explosion-proof valve 320 is connected to the top cover 300. The explosion-proof valve 320 is located inside the thinning part 310, and the explosion-proof valve 320 and the top cover 300 are integrally formed. That is, the explosion-proof valve 320 is a part of the thinning part 310. This not only ensures the overall strength of the top cover 300 and improves the stability of the connection between the explosion-proof valve 320 and the top cover 300, but also reduces the production process of connecting the explosion-proof valve 320 and the top cover 300, reduces the production cost of the top cover 300, and also reduces the weight of the top cover 300.

[0031] In this embodiment, the explosion-proof valve 320 has a weak portion 321 on the side facing away from the electrode assembly 200. It is understood that by reducing the thickness of the thinning portion 310, the space occupied by the top cover 300 along the first direction Z inside the housing 100 is reduced, thereby increasing the effective usable space of the electrode assembly 200 inside the housing 100, thus achieving the goal of improving the energy density of the single battery. Secondly, by placing the explosion-proof valve 320 in the thinning portion 310 and providing the weak portion 321 on the side of the explosion-proof valve 320 facing away from the electrode assembly 200, i.e., the thickness of the weak portion 321 is less than the thickness of the thinning portion 310, the compressive strength of the weak portion 321 is less than that of the thinning portion 310. In other words, when excessive pressure is generated inside the single battery, the weak portion 321 will open under pressure, thereby releasing the high-pressure gas generated inside the single battery to the external environment, thereby reducing the internal pressure of the single battery and effectively preventing the risk of single battery explosion.

[0032] like Figure 4 As shown, in some embodiments of this application, the single cell includes a first insulating member 400, which is disposed inside the housing 100. The first insulating member 400 is connected to the top cover 300 on the side near the electrode assembly 200. The connection method between the two includes at least one of adhesive bonding, thermal fusion bonding, snap-fit ​​bonding, or tenon and mortise bonding, so as to insulate and separate the top cover 300 and the electrode assembly 200 through the first insulating member 400 to prevent short circuit between the electrode assembly 200 and the top cover 300.

[0033] The first insulating member 400 has a first recess 411 on the side facing the top cover 300. The first recess 411 is recessed towards the side close to the electrode assembly 200. The top cover 300 also includes a protrusion 330, which is connected to the side of the thinned portion 310 facing the electrode assembly 200. The protrusion 330 is disposed in the first recess 411 so as to form a limiting connection structure through the connection between the inner wall of the protrusion 330 and the first recess 411. This not only improves the assembly efficiency between the first insulating member 400 and the top cover 300, but also improves the stability of the connection between the top cover 300 and the first insulating member 400.

[0034] like Figure 4 and Figure 5As shown, in some embodiments of this application, the protrusion 330 includes a first protrusion 331, which surrounds the explosion-proof valve 320 and engages with the first recess 411, i.e., the sidewall of the first protrusion 331 is connected to the inner wall of the first recess 411. By providing the first protrusion 331 around the periphery of the explosion-proof valve 320, not only can the mechanical strength of the weak part 321 at the explosion-proof valve 320 be increased, but the connection between the first protrusion 331 and the first recess 411 can also improve the accuracy of the assembly and the stability of the connection between the top cover 300 and the first insulating member 400.

[0035] like Figure 5 As shown, in some embodiments of this application, the weak portion 321 is recessed along the first direction Z towards the electrode assembly 200 to reduce the thickness of the weak portion 321 along the first direction Z. The weak portion 321 protrudes along the first direction Z towards the electrode assembly 200 to form a boss 350. A first protrusion 331 is arranged around the boss 350, that is, there is a gap between the first protrusion and the boss 350. The first insulating member 400 is provided with a relief groove 420 on the side facing the explosion-proof valve 320. The relief groove 420 is recessed along the first direction Z towards the side near the electrode assembly 200. The boss 350 is engaged in the relief groove 420, that is, the outer wall of the boss 350 is connected to the groove wall of the relief groove 420 to form a limit. This not only improves the assembly efficiency and accuracy between the top cover 300 and the insulating member, but also improves the stability of the connection between the top cover 300 and the first insulating member 400.

[0036] like Figure 4 and Figure 5 As shown, in some embodiments of this application, a single cell has a second direction X that is perpendicular to the first direction Z.

[0037] The protrusion 330 includes a second protrusion 332. The thinning portion 310 has second protrusions 332 at both ends along the second direction X, with the second protrusions 332 located on the side of the thinning portion 310 facing the electrode assembly 200. It should be noted that the projection of the second protrusion 332 along the first direction Z onto the end face of the thinning portion 310 facing the electrode assembly 200 can be any one or a combination of two or more of the following: a straight line structure, a curved structure, a polygonal structure, and a ring structure. This can be specifically set according to the actual situation.

[0038] In addition, the first insulating member 400 has a second recess 412 on the side facing the thinning portion 310. The second recess 412 and the first recess 411 are spaced apart along the second direction X. The second recess 412 is recessed along the first direction Z towards the side close to the electrode assembly 200. The second protrusion 332 is engaged with the second recess 412, that is, the outer wall of the second protrusion 332 is connected to the inner wall of the second recess 412 to form a limit, so as to further ensure the accuracy of the assembly between the first insulating member 400 and the top cover 300 and improve the stability of the connection between the first insulating member 400 and the top cover 300. At the same time, the second protrusion 332 can also improve the mechanical strength of both ends of the thinning portion 310 along the second direction X.

[0039] like Figures 6 to 8 As shown, in some embodiments of this application, a single battery cell includes a terminal post 700, a second insulating member 600, and a riveting portion 500. The second insulating member 600 is disposed on the side of the top cover 300 opposite to the first insulating member 400, and the riveting portion 500 is disposed on the side of the second insulating member 600 opposite to the top cover 300. The connection method between the second insulating member 600 and the top cover 300 includes at least one of snap-fit, adhesive, heat-fusion connection, and tenon-mortise connection to ensure the stability of the connection between the second insulating member 600 and the top cover 300.

[0040] In this embodiment, the second insulating member 600 is provided with a mounting groove on the side away from the electrode assembly 200 along the first direction Z. The riveting part 500 is at least partially received in the mounting groove on the side facing the first insulating member 400 along the first direction Z and is connected to the groove wall of the mounting groove to form a limiting connection structure.

[0041] In this design, one end of the electrode post 700, facing away from the electrode assembly 200 along the first direction Z, passes through the first insulating member 400, the top cover 300, and the second insulating member 600. The portion of the electrode post 700 passing through the second insulating member 600 is fixedly connected to the riveting part 500, thereby insulating and separating the electrode post 700 and the top cover 300 through the second insulating member 600 and the riveting part 500 to prevent short circuit between the electrode post 700 and the top cover 300. It should be noted that there is a gap between the electrode post 700 and the top cover 300, and the side wall of the electrode post 700 abuts against the second insulating member 600, thereby fixing the electrode post 700 to the top cover 300 through the second insulating member 600.

[0042] In addition, the end of the electrode post 700 near the electrode assembly 200 is electrically connected to the electrode assembly 200, and the electrode post 700 is welded to the electrode assembly 200 to ensure the stability of the connection between the electrode post 700 and the electrode assembly 200.

[0043] like Figure 9 and Figure 10As shown, in some embodiments of this application, the protrusion 330 includes a third protrusion 333, which is disposed on the side of the top cover 300 facing the electrode assembly 200. The third protrusion 333 is disposed around the electrode post 700, that is, the third protrusion 333 is spaced apart from the electrode post 700, so as to improve the mechanical strength of the thinned portion 310 around the electrode post 700 through the third protrusion 333.

[0044] In addition, a third recess 413 is provided on the side of the first insulating member 400 facing the thinning portion 310. The third recess 413 is recessed in the direction close to the electrode assembly 200. The third protrusion 333 is engaged in the third recess 413 so as to connect the side wall of the third protrusion 333 with the inner wall of the third recess 413, thereby improving the assembly efficiency and accuracy between the first insulating member 400 and the top cover 300, and improving the stability of the connection between the first insulating member 400 and the top cover 300.

[0045] like Figure 9 and Figure 10 As shown, in some embodiments of this application, the thinning portion 310 is recessed in the first direction Z towards the side opposite to the first insulating member 400 to form a fourth recess 340, so as to provide clearance space for the side of the first insulating member 400 facing the top cover 300 through the fourth recess 340.

[0046] The first insulating member 400 has a fourth protrusion 414 on the side facing the top cover 300. The fourth protrusion 414 is engaged with the fourth recess 340, that is, the outer wall of the fourth protrusion 414 is connected to the inner wall of the fourth recess 340, so as to improve the stability of the connection between the first insulating member 400 and the top cover 300 and the assembly efficiency.

[0047] In this embodiment, the third protrusion 333 is disposed around the fourth protrusion 414 to enhance the mechanical strength of the thinning portion 310 near the electrode assembly 200 by the third protrusion 333 disposed on the side of the thinning portion 310 facing the electrode assembly 200.

[0048] like Figure 6 and Figure 8As shown, in some embodiments of this application, the top cover 300 further includes a flange 360. The flange 360 ​​is located on the edge of the thinned portion 310 opposite to the electrode assembly 200. The height of the flange 360 ​​along the first direction Z is greater than the height of the thinned portion 310 along the first direction Z, so as to improve the mechanical strength of the edge of the thinned portion 310. It can be understood that by setting the flange 360 ​​on the side of the thinned portion 310 opposite to the electrode assembly 200 along the first direction Z, not only can the mechanical strength of the top cover 300 be increased, but also the flange 360 ​​can be prevented from affecting the effective utilization space of the electrode assembly 200 inside the housing 100, thus ensuring the energy density of the electrode assembly 200.

[0049] Secondly, this application provides a battery pack that includes the individual battery cells in any of the above embodiments.

[0050] It is understood that the battery pack has the beneficial effects of the individual cells in any of the above embodiments, which will not be elaborated here.

[0051] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limitations; therefore, other examples of exemplary embodiments may have different values.

[0052] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0053] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application.

Claims

1. A single-cell battery having a first orientation (Z), characterized in that, include: Casing (100); A top cover (300) is connected to one end of the housing (100) along the first direction (Z), and the top cover (300) includes a thinning portion (310). An electrode assembly (200) is disposed within the housing (100); An explosion-proof valve (320) is located inside the thinning part (310). The explosion-proof valve (320) is integrally formed with the top cover (300). The explosion-proof valve (320) has a weak part (321) on the side away from the electrode assembly (200).

2. The single-cell battery according to claim 1, characterized in that, The single cell also includes a first insulating member (400) disposed inside the housing (100), and the first insulating member (400) is connected to the top cover (300) on the side near the electrode assembly (200); The first insulating member (400) has a first recess (411) on the side facing the top cover (300), the first recess (411) is recessed towards the side close to the electrode assembly (200), the top cover (300) also includes a protrusion (330), the protrusion (330) is connected to the side of the thinned part (310) facing the electrode assembly (200), and the protrusion (330) is disposed in the first recess (411).

3. The single-cell battery according to claim 2, characterized in that, The protrusion (330) includes a first protrusion (331), which surrounds the explosion-proof valve (320) and is engaged with the first recess (411).

4. The single-cell battery according to claim 3, characterized in that, The weak part (321) is recessed in the direction of the first direction (Z) toward the electrode assembly (200), and the weak part (321) protrudes in the direction of the first direction (Z) toward the electrode assembly (200) to form a boss (350). The first protrusion (331) is arranged around the boss (350). The first insulating member (400) is provided with a relief groove (420) on the side facing the explosion-proof valve (320). The relief groove (420) is recessed in the direction of the first direction (Z) toward the electrode assembly (200), and the boss (350) is engaged in the relief groove (420).

5. The single-cell battery according to claim 2, characterized in that, The single cell has a second direction (X) perpendicular to the first direction (Z); The protrusion (330) includes a second protrusion (332), and the thinning portion (310) is provided with the second protrusion (332) at both ends along the second direction (X). The second protrusion (332) is located on the side of the thinning portion (310) facing the electrode assembly (200). The first insulating member (400) has a second recess (412) on the side facing the thinned portion (310). The second recess (412) and the first recess (411) are spaced apart along the second direction (X). The second recess (412) is recessed along the first direction (Z) towards the side close to the electrode assembly (200). The second protrusion (332) is engaged with the second recess (412).

6. The single-cell battery according to any one of claims 2 to 5, characterized in that, The single cell also includes a terminal post (700), a second insulating member (600), and a riveting part (500). The second insulating member (600) is disposed on the side of the top cover (300) away from the first insulating member (400), and the riveting part (500) is disposed on the side of the second insulating member (600) away from the top cover (300). The end of the pole post (700) facing away from the electrode assembly (200) along the first direction (Z) passes through the first insulating member (400), the top cover (300) and the second insulating member (600). The part of the pole post (700) passing through the second insulating member (600) is fixedly connected to the riveting part (500). The end of the pole post (700) near the electrode assembly (200) is electrically connected to the electrode assembly (200).

7. The single-cell battery according to claim 6, characterized in that, The protrusion (330) includes a third protrusion (333), which is disposed on the side of the top cover (300) facing the electrode assembly (200) and surrounds the pole post (700). The first insulating member (400) has a third recess (413) on the side facing the thinned portion (310), the third recess (413) is recessed in the direction close to the electrode assembly (200), and the third protrusion (333) is engaged in the third recess (413).

8. The single-cell battery according to claim 7, characterized in that, The thinned portion (310) is recessed along the first direction (Z) towards the side opposite to the first insulating member (400) to form a fourth recessed portion (340). The first insulating member (400) has a fourth protrusion (414) on the side facing the top cover (300), the fourth protrusion (414) is engaged with the fourth recess (340), and the third protrusion (333) is arranged around the fourth protrusion (414).

9. The single-cell battery according to claim 2, characterized in that, The top cover (300) also includes a flange (360) located on the edge of the thinned portion (310) away from the electrode assembly (200), and the height of the flange (360) along the first direction (Z) is greater than the height of the thinned portion (310) along the first direction (Z).

10. A battery pack, characterized in that, The single-cell battery includes any one of claims 1 to 9.

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