Battery cell and battery pack
By adopting the limit clamping design between plastic parts and end plates and the side setting of explosion-proof valves in the lithium-ion battery cell, the problems of pole group shaking and pole ear tearing are solved, and the reliability and safety of the battery cell are improved.
Patent Information
- Application Number
- CN202421539885.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-01
- Publication Date
- 2025-07-08
- Estimated Expiration
- 2034-07-01
AI Technical Summary
In the existing lithium-ion battery cells, the assembly gap between the electrode group and the housing causes easy relative movement between the end plate and the plastic layer, which may cause tearing of the electrode ears and short circuits, and the explosion-proof valve exhaust path is long, affecting safety and reliability.
A plastic part is fixed to the cover plate, and a slot is provided on the end plate. The outer edge of the plastic part abuts upwards the X-direction and Y-direction, and is snapped through the limiting part. The end plate and the plastic part can be detached and fit. The cover plate and the end plate are in rigid contact, and the explosion-proof valve is arranged on the side of the housing.
It improves the connection firmness between the end plate and the plastic parts, reduces the risk of extreme ear tear, shortens the gas discharge path, and enhances the reliability and safety of the battery cell.
Smart Images
Figure CN223079211U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of energy storage devices, and more particularly, to a battery cell and a battery pack. Background Art
[0002] With the increasing maturity of lithium-ion battery technology, 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 day by day.
[0003] The lithium battery cell is the core component of the battery pack, and its structural design is crucial for the stability and safety of the battery cell. In existing battery cells, the electrode group is usually arranged in the housing, an end plate is installed at the end of the electrode group, and a plastic layer is provided between the end plate and the cover plate. However, there is generally an assembly gap between the electrode group and the housing, which makes it easy for the electrode group and the housing to have a relative position. The end plate and the plastic layer only contact but are not connected in the direction perpendicular to the cover plate. When there is a relative displacement between the electrode group and the housing, it is easy to cause relative movement between the end plate and the plastic layer. The movement of the end plate may cause the relatively weak tab to tear, and the torn tab may extend from the gap between the end plate and the plastic layer and overlap with the housing, resulting in a short circuit. Summary of the Utility Model
[0004] The purpose of this application is to provide a battery cell and a battery pack for at least one technical problem involved in the background art.
[0005] To achieve the above purpose, this application adopts the following technical solutions:
[0006] One aspect of this application provides a battery cell, including a cover plate, a plastic part, and an end plate. The plastic part is fixed to the cover plate. A notch facing the cover plate is formed on the end plate. The plastic part is located in the notch. The outer edge of the plastic part abuts against the inner edge of the notch both in the X direction and in the Y direction, and the X direction and the Y direction are perpendicular to each other.
[0007] Optionally, a first limiting part is formed on the inner edge of the notch, and a second limiting part is formed on the outer edge of the plastic part. The first limiting part and the second limiting part are detachably matched.
[0008] The beneficial effect of this technical solution is that it enables the detachable cooperation between the end plate and the plastic part, so as to achieve the purpose of repairing and replacing the cover plate, the end plate and other components inside the battery cell.
[0009] Optionally, the first limiting part and the second limiting part are snap-connected.
[0010] The beneficial effect of this technical solution is that, on the premise of ensuring the detachable cooperation between the end plate and the plastic part, the connection firmness between the end plate and the plastic part is improved, and thus the reliability of the battery cell is improved.
[0011] Optionally, the first limiting portion is a clamping groove formed on the inner edge of the notch, and the second limiting portion is a boss formed on the outer edge of the plastic part, and the clamping groove is clamped with the boss.
[0012] The beneficial effect of this technical solution is that: compared with setting a boss on the inner edge of the notch, it is easier to machine the clamping groove on the inner edge of the notch.
[0013] Optionally, the cross-section of the clamping groove is semi-circular, and / or the cross-section of the boss is semi-circular.
[0014] The beneficial effect of this technical solution is that: in this way, not only can the clamping between the first limiting portion and the second limiting portion be realized, but also the disassembly and assembly between the first limiting portion and the second limiting portion are facilitated due to the arc shape of the semi-circle, improving the disassembly and assembly efficiency between the end plate and the plastic part.
[0015] Optionally, the cross-section of the clamping groove is polygonal, and / or the cross-section of the boss is polygonal.
[0016] The beneficial effect of this technical solution is that: in this way, not only can the clamping between the first limiting portion and the second limiting portion be realized, but also the disassembly and assembly between the first limiting portion and the second limiting portion are facilitated due to the polygonal shape, improving the disassembly and assembly efficiency between the end plate and the plastic part.
[0017] Optionally, the first limiting portion is a boss formed on the inner edge of the notch, the boss extends in the Y direction, the second limiting portion is a clamping groove formed on the outer edge of the plastic part, and the clamping groove is clamped with the boss.
[0018] The beneficial effect of this technical solution is that: in this way, the boss can play a role in improving the structural strength of the end plate, making the end plate not easily deformed.
[0019] Optionally, in the Z direction, the end plate abuts against the cover plate, and the X direction and the Y direction are both perpendicular to the Z direction.
[0020] The beneficial effect of this technical solution is that: in the prior art, the end plate abuts against the plastic part in a direction perpendicular to the cover plate. Since the plastic part is an elastic structure, it is difficult for the plastic part to limit the pole group when the pole group shakes relative to the housing. In this application, the cover plate is a rigid structure, and the abutment between the end plate and the cover plate is a rigid contact. This rigid contact can play a good limiting role on the end plate and the pole group connected to the end plate, making it difficult for the pole group to shake. Moreover, when the pole group shakes, it is easy to cause damage to the internal components of the battery cell. By abutting the end plate against the cover plate to limit the pole group, while making the pole group not easily shake, it also effectively reduces the damage probability of the internal components of the battery cell; and, through the rigid limit of the cover plate, the end plate is not easily deformed.
[0021] Optionally, the battery cell further includes a housing and an explosion-proof valve. The housing has a first end face and a second end face. The cover plate is installed on the first end face, and the explosion-proof valve is installed on the second end face. The first end face is perpendicular to the second end face.
[0022] The beneficial effect of this technical solution is that: generally, when the battery cell is in use, the end face where the cover plate of the housing is located (i.e., the first end face) is the top surface of the housing, and the explosion-proof valve is generally also installed on the first end face. However, in this case, when gas is generated inside the battery cell, it needs to move a relatively long distance and for a long time to reach the explosion-proof valve. In this application, the explosion-proof valve is arranged on the second end face. When the first end face is at the top of the battery cell, the second end face is the side surface of the housing. Arranging the explosion-proof valve on the second end face can effectively reduce the length of the gas discharge path inside the battery cell and shorten the time used for discharging gas.
[0023] Another aspect of this application provides a battery pack, including the battery cell as described in this application.
[0024] The technical solution provided by this application can achieve at least one of the following beneficial effects:
[0025] For the battery cell and the battery pack provided by this application, since the outer edge of the plastic part abuts against the inner edge of the notch in both the X direction and the Y direction, when the battery cell is in use, it is not easy for relative movement to occur between the end plate and the plastic part in the direction parallel to the cover plate. Furthermore, it is not easy for the pole ear to be torn due to relative movement between the end plate and the plastic part in the direction parallel to the cover plate. Since the plastic part is located in the notch on the end plate, even if the pole ear is torn, it is difficult for the torn pole ear to protrude from between the plastic part and the end plate. Furthermore, it is not easy for the pole ear to overlap with the housing inside the housing.
[0026] The additional technical features and their advantages of this application will be more clearly described in the following description content, or can be understood through the specific practice of this application. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the technical solutions of the specific embodiments of this application, the drawings required for use in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.
[0028] Figure 1 An exploded structural schematic diagram of an embodiment of the battery cell provided by an embodiment of this application;
[0029] Figure 2 A partial cross-sectional structural schematic diagram of an embodiment of the battery cell provided by an embodiment of this application;
[0030] Figure 3 is Figure 2 a partial enlarged schematic view at position A in
[0031] Figure 4 a top view structural schematic diagram of an implementation manner of the end plate provided by an embodiment of the present application;
[0032] Figure 5 is Figure 4 a sectional structural schematic diagram at B-B in
[0033] Figure 6 is Figure 5 a partial enlarged schematic view of
[0034] Figure 7 is Figure 4 a sectional structural schematic diagram at C-C in
[0035] Figure 8 a partial front view structural schematic diagram of an implementation manner of the battery cell provided by an embodiment of the present application;
[0036] Figure 9 a partial left view structural schematic diagram of an implementation manner of the battery cell provided by an embodiment of the present application.
[0037] Reference numerals:
[0038] 01, cover plate; 02, end plate;
[0039] 03, electrode group; 04, insulating film;
[0040] 05, housing; 06, explosion-proof valve;
[0041] 07, plastic part; 08, tab;
[0042] 09, first limiting part; 10, second limiting part;
[0043] 11, notch. Specific embodiments
[0044] Next, the technical solutions of the present application will be described clearly and completely with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts shall fall within the protection scope of the present application.
[0045] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present application. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.
[0046] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.
[0047] As Figures 1 to 9 shown, one aspect of the present application provides a battery cell, including a cover plate 01, a plastic part 07, and an end plate 02. The plastic part 07 is fixed to the cover plate 01. A notch 11 facing the cover plate 01 is formed on the end plate 02. The plastic part 07 is located within the notch 11. The outer edge of the plastic part 07 abuts against the inner edge of the notch 11 both in the X direction and in the Y direction, and the X direction and the Y direction are perpendicular to each other. In the embodiment of the present application, preferably, both the X direction and the Y direction are parallel to the cover plate 01.
[0048] For the battery cell provided by the present application, since the outer edge of the plastic part 07 abuts against the inner edge of the notch 11 both in the X direction and in the Y direction, when the battery cell is in use, relative movement between the end plate 02 and the plastic part 07 in the direction parallel to the cover plate 01 is not likely to occur, and thus it is not likely that the tab 08 is torn due to the relative movement between the end plate 02 and the plastic part 07 in the direction parallel to the cover plate 01. Since the plastic part 07 is located within the notch 11 on the end plate 02, even if the tab 08 is torn, the torn tab 08 is difficult to extend out between the plastic part 07 and the end plate 02, and thus it is not likely that the tab 08 in the housing is in lap joint with the housing; moreover, in the prior art, the insulating film 04 (also called mylar) is coated on the outer wall of the end plate 02 and the outer edge of the plastic part 07. In the present application, the plastic part 07 is located within the notch 11 on the end plate 02, and the length of the end plate 02 in the direction perpendicular to the cover plate 01 needs to be increased to make up for the length occupied by the plastic part 07 in the prior art. This increases the contact area between the end plate 02 and the insulating film 04, which is more conducive to the positioning and hot melting process of the insulating film 04.
[0049] Optionally, a first limiting portion 09 is formed on the inner edge of the notch 11, and a second limiting portion 10 is formed on the outer edge of the plastic part 07. The first limiting portion 09 and the second limiting portion 10 are detachably engaged. This enables the detachable cooperation between the end plate 02 and the plastic part 07, so as to achieve the purpose of repairing and replacing the cover plate 01, the end plate 02 and other components inside the battery cell.
[0050] Optionally, the first limiting portion 09 and the second limiting portion 10 are snap-connected. In this way, on the premise of ensuring the detachable cooperation between the end plate 02 and the plastic part 07, the connection firmness between the end plate 02 and the plastic part 07 is improved, thereby improving the reliability of the battery cell. Of course, the first limiting portion 09 and the second limiting portion 10 can also be connected by screws made of insulating materials.
[0051] Optionally, the first limiting portion 09 is a clamping groove formed on the inner edge of the notch 11, and the second limiting portion 10 is a convex platform formed on the outer edge of the plastic part 07. The clamping groove and the convex platform are snap-connected. Compared with setting a convex platform on the inner edge of the notch 11, it is easier to process the clamping groove on the inner edge of the notch 11.
[0052] Optionally, the cross-section of the clamping groove is semi-circular, and / or the cross-section of the convex platform is semi-circular. That is to say, the embodiments of the present application at least include the following three implementation manners: the cross-section of the clamping groove is semi-circular; the cross-section of the convex platform is semi-circular; the cross-section of the clamping groove is semi-circular and the cross-section of the convex platform is semi-circular. In this way, not only can the snap connection between the first limiting portion 09 and the second limiting portion 10 be realized, but also the arc shape of the semi-circle facilitates the disassembly and assembly between the first limiting portion 09 and the second limiting portion 10, improving the disassembly and assembly efficiency between the end plate 02 and the plastic part 07.
[0053] Optionally, the cross-section of the clamping groove is polygonal, and / or the cross-section of the convex platform is polygonal. That is to say, the embodiments of the present application at least include the following three implementation manners: the cross-section of the clamping groove is polygonal; the cross-section of the convex platform is polygonal; the cross-section of the clamping groove is polygonal and the cross-section of the convex platform is polygonal. In this way, not only can the snap connection between the first limiting portion 09 and the second limiting portion 10 be realized, but also the polygonal shape facilitates the disassembly and assembly between the first limiting portion 09 and the second limiting portion 10, improving the disassembly and assembly efficiency between the end plate 02 and the plastic part 07. The polygon is preferably a triangle. Of course, the cross-section of the clamping groove can also be square, and / or the cross-section of the convex platform can be square.
[0054] Optionally, the first limiting portion 09 is a boss formed on the inner edge of the notch 11, the boss Y extends upward, and the second limiting portion 10 is a clamping groove formed on the outer edge of the plastic part 07, and the clamping groove is clamped with the boss. In this way, the boss can play a role in improving the structural strength of the end plate 02, making the end plate 02 not easily deformed.
[0055] Optionally, in the Z direction, the end plate 02 abuts against the cover plate 01, and the X direction and the Y direction are both perpendicular to the Z direction. In the prior art, the end plate 02 abuts against the plastic part 07 in a direction perpendicular to the cover plate 01. Since the plastic part 07 is an elastic structure, it is difficult for the plastic part 07 to limit the pole group 03 when the pole group 03 shakes relative to the housing. In this application, the cover plate 01 is a rigid structure, and the abutment between the end plate 02 and the cover plate 01 is a rigid contact. This rigid contact can play a better limiting role on the end plate 02 and the pole group 03 connected to the end plate 02, making it difficult for the pole group 03 to shake. Moreover, when the pole group 03 shakes, it is easy to cause damage to the internal components of the battery cell. By limiting the pole group 03 through the abutment of the end plate 02 and the cover plate 01, while making the pole group 03 not easily shake, it also effectively reduces the damage probability of the internal components of the battery cell; and, through the rigid limit of the cover plate 01, the end plate 02 is not easily deformed.
[0056] Optionally, the battery cell further includes a housing 05 and an explosion-proof valve 06. The housing 05 has a first end face and a second end face. The cover plate 01 is installed on the first end face, and the explosion-proof valve 06 is installed on the second end face. The first end face is perpendicular to the second end face. Generally, when the battery cell is in use, the end face where the cover plate 01 is located on the housing 05 (i.e., the first end face) is the top face of the housing 05, and the explosion-proof valve 06 is generally also installed on the first end face. However, in this case, when gas is generated inside the battery cell, it needs to move a relatively long distance and for a long time to reach the explosion-proof valve 06. In this application, the explosion-proof valve 06 is arranged on the second end face. When the first end face is at the top of the battery cell, the second end face is the side face of the housing 05. Arranging the explosion-proof valve 06 on the second end face can effectively reduce the length of the gas discharge path inside the battery cell and shorten the time used to discharge the gas.
[0057] Another aspect of the present application provides a battery pack, including the battery cell provided by the embodiments of the present application.
[0058] The battery pack provided by the present application uses the battery cell provided by the present application. Since the outer edge of the plastic part 07 is in contact with the inner edge of the notch 11 in both the X direction and the Y direction, when the battery cell is in use, relative movement between the end plate 02 and the plastic part 07 in a direction parallel to the cover plate 01 is not likely to occur, and thus the ear 08 is not likely to be torn due to relative movement between the end plate 02 and the plastic part 07 in a direction parallel to the cover plate 01. Since the plastic part 07 is located in the notch 11 on the end plate 02, even if the ear 08 is torn, the torn ear 08 is difficult to extend out between the plastic part 07 and the end plate 02, and thus the situation where the ear 08 is in lap joint with the housing 05 in the housing 05 is not likely to occur.
[0059] 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 them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A battery cell, characterized in that, It includes a cover plate, a plastic part, and an end plate. The plastic part is fixed to the cover plate. A notch facing the cover plate is formed on the end plate. The plastic part is located within the notch. The outer edge of the plastic part abuts against the inner edge of the notch both in the X direction and in the Y direction, and the X direction and the Y direction are perpendicular to each other.
2. The battery cell according to claim 1, wherein, A first limiting part is formed on the inner edge of the notch, and a second limiting part is formed on the outer edge of the plastic part. The first limiting part and the second limiting part are detachably engaged.
3. The battery cell according to claim 2, wherein, The first limiting part and the second limiting part are snap-fitted.
4. The battery cell according to claim 3, wherein, The first limiting part is a clamping groove formed on the inner edge of the notch, and the second limiting part is a boss formed on the outer edge of the plastic part. The clamping groove and the boss are snap-fitted.
5. The battery cell according to claim 4, characterized in that, The cross-section of the clamping groove is semi-circular, and / or the cross-section of the boss is semi-circular.
6. The battery cell according to claim 4, wherein, The cross-section of the clamping groove is polygonal, and / or the cross-section of the boss is polygonal.
7. The battery cell according to claim 3, wherein, The first limiting part is a boss formed on the inner edge of the notch. The boss extends in the Y direction. The second limiting part is a clamping groove formed on the outer edge of the plastic part. The clamping groove and the boss are snap-fitted.
8. The battery cell according to any one of claims 1 to 7, characterized in that, In the Z direction, the end plate abuts against the cover plate, and both the X direction and the Y direction are perpendicular to the Z direction.
9. The battery cell according to any one of claims 1 to 7, characterized in that, The battery cell further includes a housing and an explosion-proof valve. The housing has a first end face and a second end face. The cover plate is installed on the first end face, and the explosion-proof valve is installed on the second end face. The first end face is perpendicular to the second end face.
10. Battery pack, characterized in that, It includes a battery cell according to any one of claims 1 to 9.