A lower plastic structure, a battery cover and a battery

Abstract

The utility model discloses a kind of lower plastic structure, battery cover plate and battery.Wherein, lower plastic structure includes the positive lower plastic and negative lower plastic of cooperation use, first boss is provided on the positive lower plastic, second boss is provided on the negative lower plastic, the both ends of the first boss are respectively provided with inwardly extending, for the positive extension wall of welding connection with insulating film, the both ends of the second boss are respectively provided with inwardly extending, for the negative extension wall of welding connection with insulating film.This application guarantees that large size battery pole group insulating film reliably wraps up big R angle, and ensures the stable welding connection of insulating film and lower plastic.

Description

Technical Field

[0001] This utility model relates to the field of battery structure technology, specifically to a lower plastic structure, a battery cover, and a battery. Background Technology

[0002] With the continuous development of power battery technology, in order to improve battery energy density and space utilization, the width of batteries is being designed to be larger and larger. This trend places higher demands on the internal structure of the battery, especially the insulation protection of the electrode assembly.

[0003] During battery production, an insulating film is typically wrapped around the outside of the electrode assembly to ensure electrical isolation. As the width of the electrode assembly increases, the requirements for the radius (R) of the insulating film during wrapping also increase to ensure that the insulating film can fit more snugly and reliably around the edges of the electrode assembly and to avoid problems such as loose wrapping or wrinkles.

[0004] However, in existing battery structures, the terminals are typically located at the two ends of the battery. This layout limits the available space at the ends of the electrode assembly, making it difficult to design a larger radius (R-angle). Forcibly increasing the R-angle to improve the insulating film's wrapping effect can easily lead to insufficient hot-melt welding positions near the ends of the electrode assembly, thus affecting the reliability of the connection between the insulating film and the underlying plastic, increasing the risk of detachment. This technical dilemma is particularly prominent in large-size battery designs, urgently requiring a solution that can ensure a reliable connection between the insulating film and the underlying plastic while maintaining a sufficient R-angle. Utility Model Content

[0005] In response to the technical problem mentioned in the prior art that if the radius (R) of the existing structure is increased to ensure better wrapping of the electrode assembly by the insulating film, there will be no hot-melt welding positions on both sides, making it easy for the insulating film to detach from the lower plastic. This application provides a lower plastic structure, a battery cover, and a battery.

[0006] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0007] First aspect

[0008] This application provides a lower plastic structure, including a positive electrode lower plastic and a negative electrode lower plastic used in conjunction. The positive electrode lower plastic is provided with a first protrusion, and the negative electrode lower plastic is provided with a second protrusion. Both ends of the first protrusion are respectively provided with a positive electrode extension wall extending inward for welding to an insulating film. Both ends of the second protrusion are respectively provided with a negative electrode extension wall extending inward for welding to an insulating film.

[0009] Wherein, the positive electrode extension wall is a first extension wall, and the negative electrode extension wall is a second extension wall; the two first extension walls are symmetrically arranged, and the inner end face of each first extension wall is connected to the corresponding side of the first boss through a first connecting R-angle; the two second extension walls are symmetrically arranged, and the inner end face of each second extension wall is connected to the corresponding side of the second boss through a second connecting R-angle.

[0010] The outer end face of each first extension wall is flush with the outer end face of the corresponding side of the first boss at the connection point; the outer end face of each second extension wall is flush with the outer end face of the corresponding side of the second boss at the connection point. The upper end face of each first extension wall is flush with the upper end face of the corresponding side of the first boss; the upper end face of each second extension wall is flush with the upper end face of the corresponding side of the second boss.

[0011] The two first extension walls are integrally formed with the corresponding side of the first boss; the two second extension walls are integrally formed with the corresponding side of the second boss.

[0012] Wherein, the positive electrode extension wall is a third extension wall, and the negative electrode extension wall is a fourth extension wall; the two third extension walls are symmetrically arranged, and the upper end face of each third extension wall is lower than the upper end face of the corresponding side of the first boss; the two fourth extension walls are symmetrically arranged, and the upper end face of each fourth extension wall is lower than the upper end face of the corresponding side of the second boss.

[0013] The outer end face of each third extension wall is flush with the outer end face of the corresponding side of the first boss at the connection point; the outer end face of each fourth extension wall is flush with the outer end face of the corresponding side of the second boss at the connection point. The two third extension walls are integrally formed with the corresponding side of the first boss; the two fourth extension walls are integrally formed with the corresponding side of the second boss.

[0014] Second aspect

[0015] This application provides a battery cover, including a mating aluminum plate and the aforementioned lower plastic structure.

[0016] Third aspect

[0017] This application provides a battery, characterized in that it includes the aforementioned battery cover.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] While ensuring reliable wrapping of the insulating film (large radius) for large-size battery electrode groups, a stable welding connection between the insulating film and the underlying plastic is ensured, specifically including the following:

[0020] (1) By adding inwardly extending walls at both ends of the lower plastic boss, an additional and ample welding area is provided for the insulating film. This makes it possible to design a larger radius while ensuring welding strength.

[0021] (2) The extension wall smoothly transitions to the main body of the boss by connecting the R-corner, which not only enhances the structural strength of the extension wall itself, but also provides a smoother wrapping path for the insulating film, reduces stress concentration, and prevents the connection from falling off; in addition, the extension wall and the lower plastic main body are integrally molded, which fundamentally avoids the risk of failure caused by poor connection.

[0022] (3) This application provides two extension wall designs: flush and recessed. Flush design: ensures the flatness of the upper surface, which is beneficial for the cooperation with other components; Recessed design: provides more ample assembly space for other components such as aluminum plates, and improves the compatibility of the overall structure. Through ingenious local structural design, the internal space is effectively utilized without increasing the overall size, supporting the development needs of high energy density batteries. Attached Figure Description

[0023] Figure 1 The diagram shown is a schematic of the lower plastic structure in the prior art;

[0024] In the diagram, the radius (R) is 14.

[0025] Figure 2 The diagram shown is a schematic diagram of the first embodiment of the lower plastic structure provided in this application;

[0026] In the figure, the first extension wall is 1, the first positive electrode lower plastic is 2, the first connecting R-angle is 3, the second extension wall is 4, the first negative electrode lower plastic is 5, and the second connecting R-angle is 6.

[0027] Figure 3 The diagram shown is a schematic diagram of the first embodiment of the positive electrode plastic provided in this application;

[0028] Figure 4 The diagram shown is a schematic diagram of the first embodiment of the negative electrode plastic provided in this application;

[0029] Figure 5 The diagram shown is a schematic diagram of the battery explosion structure of the first embodiment of the plastic structure provided in this application.

[0030] In the figure, 7 is the insulating film, 8 is the electrode assembly, 9 is the negative electrode post, 10 is the positive electrode post, and 11 is the aluminum plate.

[0031] Figure 6 The diagram shown is a schematic diagram of the second embodiment of the positive electrode plastic provided in this application;

[0032] In the diagram, the third extension wall is 12;

[0033] Figure 7 The diagram shown is a schematic diagram of the second embodiment of the negative electrode plastic provided in this application;

[0034] In the diagram, the fourth extension wall is 13;

[0035] Figure 8 The diagram shown is a schematic diagram of the battery explosion structure according to the second embodiment of the plastic structure provided in this application. Detailed Implementation

[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0037] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0038] In the description of this patent, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting; they can refer to a direct connection or an indirect connection. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0039] like Figures 2-8 The diagram shows the structure of an embodiment provided by this utility model.

[0040] This embodiment provides a lower plastic structure, including a positive electrode lower plastic 2 and a negative electrode lower plastic 5 used in conjunction. The positive electrode lower plastic 2 is provided with a first protrusion, and the negative electrode lower plastic 5 is provided with a second protrusion. Both ends of the first protrusion are respectively provided with a positive electrode extension wall extending inward for welding to the insulating film 7. Both ends of the second protrusion are respectively provided with a negative electrode extension wall extending inward for welding to the insulating film 7.

[0041] It should be noted that, as Figure 1 As shown, since the first and second bosses are relatively small, if the radius 14 is too large, there will be no position for welding the insulating film later. Therefore, to solve the above problem, the radius of the first and second bosses is increased, and an extension wall is set at the edge of the boss. Two structures are adopted for the extension wall.

[0042] The first structure is as follows:

[0043] The positive electrode extension wall is a first extension wall 1, and the negative electrode extension wall is a second extension wall 4;

[0044] The two first extension walls 1 are symmetrically arranged, and the inner end face of each first extension wall 1 is connected to the corresponding side of the first boss through a first connecting R angle 3; the two second extension walls 4 are symmetrically arranged, and the inner end face of each second extension wall 4 is connected to the corresponding side of the second boss through a second connecting R angle 6.

[0045] The outer end face of each first extension wall 1 is flush with the outer end face of the corresponding side of the first boss; the outer end face of each second extension wall 4 is flush with the outer end face of the corresponding side of the second boss.

[0046] The upper end face of each first extension wall 1 is flush with the upper end face of the corresponding side of the first boss; the upper end face of each second extension wall 4 is flush with the upper end face of the corresponding side of the second boss.

[0047] The two first extension walls 1 are integrated with the corresponding side of the first protrusion; the two second extension walls 4 are integrated with the corresponding side of the second protrusion.

[0048] It should be noted that in the above structure, the extended wall protrudes from the boss, providing a location for welding the insulating film. The extended walls are connected by a connecting radius (R-angle). This radius ensures that the connection point between the extended wall and the boss is not parallel to the plane of the extended wall, preventing a parallel surface from pressing down on the electrode assembly, causing electrode powder shedding, and affecting cell performance. Simultaneously, the connecting radius integrates the extended wall and the boss into a single unit, ensuring that the contact points between the boss, the extended wall, and the electrode assembly are flat. This prevents a single extended wall from being easily inserted into the electrode assembly during assembly, which could lead to electrode powder shedding and affect battery performance.

[0049] The second structure is as follows:

[0050] The positive electrode extension wall is the third extension wall 12, and the negative electrode extension wall is the fourth extension wall 13;

[0051] The two third extension walls 12 are symmetrically arranged, and the upper end face of each third extension wall 12 is lower than the upper end face of the corresponding side of the first boss; the two fourth extension walls 13 are symmetrically arranged, and the upper end face of each fourth extension wall 13 is lower than the upper end face of the corresponding side of the second boss.

[0052] The outer end face of each third extension wall 12 is flush with the outer end face of the corresponding side of the first boss; the outer end face of each fourth extension wall 13 is flush with the outer end face of the corresponding side of the second boss.

[0053] The two third extension walls 12 are integrated with the corresponding side of the first protrusion; the two fourth extension walls 13 are integrated with the corresponding side of the second protrusion.

[0054] It should be noted that in the above structure, the extension wall extends out of the boss to provide a position for welding the insulating film. The extension wall is lower than the surface of the boss, and the height reduction is greater than the amount of compression of the electrode group by the boss. This prevents the extension wall from being inserted into the electrode group, which would cause the electrode group to shed powder and affect the performance of the cell.

[0055] In addition, this application also provides a battery cover, including a mating aluminum plate 11 and the aforementioned lower plastic structure.

[0056] In addition, this application also provides a battery, including the battery cover, and also includes a pole group 8, a negative terminal 9, a positive terminal 10 and other structures. This structure adopts the prior art and will not be described in detail here.

[0057] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A lower plastic structure, characterized in that, It includes a positive electrode lower plastic (2) and a negative electrode lower plastic (5) used in conjunction. The positive electrode lower plastic (2) is provided with a first protrusion, and the negative electrode lower plastic (5) is provided with a second protrusion. Both ends of the first protrusion are respectively provided with a positive electrode extension wall extending inward for welding to the insulating film (7), and both ends of the second protrusion are respectively provided with a negative electrode extension wall extending inward for welding to the insulating film (7).

2. The lower plastic structure according to claim 1, characterized in that, The positive electrode extension wall is a first extension wall (1), and the negative electrode extension wall is a second extension wall (4); The two first extension walls (1) are symmetrically arranged, and the inner end face of each first extension wall (1) is connected to the corresponding side of the first boss through a first connecting R angle (3); the two second extension walls (4) are symmetrically arranged, and the inner end face of each second extension wall (4) is connected to the corresponding side of the second boss through a second connecting R angle (6).

3. The lower plastic structure according to claim 2, characterized in that, The outer end face of each first extension wall (1) is flush with the connection point of the outer end face of the corresponding side of the first boss; the outer end face of each second extension wall (4) is flush with the connection point of the outer end face of the corresponding side of the second boss.

4. The lower plastic structure according to claim 3, characterized in that, The upper end face of each first extension wall (1) is flush with the upper end face of the corresponding side of the first boss; the upper end face of each second extension wall (4) is flush with the upper end face of the corresponding side of the second boss.

5. The lower plastic structure according to claim 2, characterized in that, Both first extension walls (1) are integrally formed with the corresponding side of the first boss; both second extension walls (4) are integrally formed with the corresponding side of the second boss.

6. The lower plastic structure according to claim 1, characterized in that, The positive electrode extension wall is the third extension wall (12), and the negative electrode extension wall is the fourth extension wall (13); The two third extension walls (12) are symmetrically arranged, and the upper end face of each third extension wall (12) is lower than the upper end face of the corresponding side of the first boss; the two fourth extension walls (13) are symmetrically arranged, and the upper end face of each fourth extension wall (13) is lower than the upper end face of the corresponding side of the second boss.

7. A lower plastic structure according to claim 6, characterized in that, The outer end face of each third extension wall (12) is flush with the outer end face of the corresponding side of the first boss; the outer end face of each fourth extension wall (13) is flush with the outer end face of the corresponding side of the second boss.

8. The lower plastic structure according to claim 6, characterized in that, The two third extension walls (12) are integrated with the corresponding side of the first boss; the two fourth extension walls (13) are integrated with the corresponding side of the second boss.

9. A battery cover, characterized in that, It includes a light aluminum plate (11) used in conjunction with the lower plastic structure as described in any one of claims 1-8.

10. A battery, characterized in that, Includes the battery cover as described in claim 9.

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