Top cover structure and battery

Abstract

A top cover structure and a battery, the top cover structure comprising: a cover plate (3), the cover plate (3) being made of an electrically conductive material; a first pole (4), located on a first surface (31) of the cover plate (3) and fixedly connected to the cover plate (3); a second pole (5), penetrating through the first surface (31) and a second surface (32) of the cover plate (3), and insulated from the cover plate (3); and a connecting block (6), located on the second surface (32) of the cover plate (3) and fixedly connected to the cover plate (3), the connecting block (6) being used to connect to a first tab (21) of a battery cell (2). In the described technical solution, the number of independent components that need to be configured is reduced, production and assembly processes of the components are simplified, and working efficiency is improved. Moreover, the number of independent components being reduced makes it more convenient to control the quality of each component, thereby facilitating management and control of the quality of the battery formed by subsequent assembly. Furthermore, the resistance of a transmission path is reduced, the internal resistance of the battery is reduced after the components are assembled to form the battery, and the working efficiency of the battery is improved.

Description

Top cover structure and battery Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a top cover structure and a battery. Background Art

[0002] In the existing battery structure, the pole is passed through the cover plate and maintains an insulated connection with the cover plate; a connecting piece is provided between the pole and the battery cell, and the electrical connection between the pole and the tab of the battery cell is achieved through the provided connecting piece.

[0003] In the existing battery structure, there are many independent components, which leads to more production and assembly processes and makes the overall quality control of the battery more difficult. The conductive components in multiple independent components are connected (such as welding) to realize the transmission path of the battery cell tab-connecting plate-electrode. The battery itself is affected by the large resistance at the connection positions of different components, which makes the battery itself have a large internal resistance and also causes the problem of low battery efficiency.

[0004] Summary of the Invention

[0005] The present application provides a top cover structure and a battery, which simplifies the battery structure, simplifies the production and assembly processes of battery components, and facilitates the control of battery quality; reduces the internal resistance of the battery itself, and improves the working efficiency of the battery.

[0006] In a first aspect, the present application provides a top cover structure, comprising:

[0007] A cover plate, wherein the cover plate is made of a conductive material;

[0008] A first pole, located on the first surface of the cover plate and fixedly connected to the cover plate;

[0009] a second pole, passing through the first surface and the second surface of the cover plate and insulated from the cover plate;

[0010] a connecting block, located on the second surface of the cover plate and fixedly connected to the cover plate;

[0011] The connecting block is used to connect to the first tab of the battery cell;

[0012] The first surface and the second surface are two surfaces facing away from each other in the thickness direction of the cover plate, and the second surface is a side of the cover plate facing the battery cell.

[0013] In the above technical solution, by setting the first pole and the connecting block, the number of independent components that need to be set is reduced, the production and assembly processes of the components are simplified, and work efficiency is improved; at the same time, the reduction in the number of independent components also makes it more convenient to control the quality of each component, and facilitates the quality control of the subsequent assembly to form a battery; and, by directly connecting the connecting block with the first pole ear, compared with the existing method of connecting the pole and the pole ear with a connecting piece, the resistance of the transmission path is reduced. After the battery is assembled, the internal resistance of the battery itself is reduced, thereby improving the working efficiency of the battery.

[0014] In a specific embodiment, the first electrode is a positive electrode, and the cover is made of aluminum or an aluminum alloy.

[0015] In the above technical solution, the positive electrode column and the cover plate are integrally formed, and the cover plate is made of aluminum or aluminum alloy, which reduces the number of independent components and the internal resistance of the battery while maintaining a low cost.

[0016] In a specific embodiment, the first electrode is a negative electrode, and the cover is made of copper or a copper alloy.

[0017] In the above technical solution, the cover plate is made of copper or copper alloy, which has lower resistivity and higher current transmission efficiency compared to aluminum and aluminum alloy.

[0018] In a specific implementation manner, the first pole and the connecting block are integrally formed with the cover plate.

[0019] In the above technical solution, the first pole and the connecting block are integrally formed with the cover plate, which simplifies the subsequent assembly process compared to welding and other methods. In addition, the integral molding method can minimize the resistance of the current in the transmission path of the connecting block-cover plate-first pole, reduce the loss of the battery itself, and improve the working efficiency of the battery.

[0020] In a specific embodiment, a plastic plate is further included. The plastic plate is attached to the second surface of the cover plate, and a avoidance hole is opened on the plastic plate for the second pole and the connecting block to pass through.

[0021] In the above technical solution, the plastic plate is provided to separate the cover plate and the battery cell, which plays a certain buffering role and absorbs the external impact on the cover plate; it also plays the role of insulating and isolating the cover plate and the battery cell, avoiding the risk of short circuit between the two when the cover plate directly contacts the battery cell, thereby improving the stability of the battery.

[0022] In a specific embodiment, the connecting block extends through the avoidance hole to a side of the plastic plate facing away from the cover plate;

[0023] The distance between the surface of the connecting block facing away from the cover plate and the surface of the plastic plate facing away from the cover plate is a, and a satisfies: <a≤5mm。

[0024] In the above technical solution, the connecting block protrudes from the plastic plate by a sufficiently large distance, which makes it more convenient to connect the connecting block to the first pole ear than when the surface of the connecting block facing the battery cell is flush with the surface of the plastic plate facing away from the cover plate, or even when the surface of the plastic plate facing away from the cover plate faces the cover plate. At the same time, the value of the spacing a is limited to no more than 5 mm, so as to avoid the problem of excessive gap between the plastic plate and the battery cell after the battery is assembled due to excessive spacing, thereby alleviating the problems of space waste and reduced energy density of the battery.

[0025] In a specific embodiment, the second pole extends through the avoidance hole to a side of the plastic plate facing away from the cover plate;

[0026] One end of the second pole passing through the avoidance hole is connected to a transfer plate;

[0027] The distance between the side surface of the adapter plate facing away from the cover plate and the surface of the plastic plate facing away from the cover plate is b;

[0028] a and b satisfy: a=b.

[0029] In the above technical solution, when the battery is assembled, the connecting block and the adapter are synchronously abutted against the corresponding first pole tab and second pole tab, and then fixedly connected by welding. This can ensure the synchronization of the connection with the first pole tab and the second pole tab during the assembly process, facilitate the assembly operation, and improve production efficiency.

[0030] In a second aspect, the present application further provides a battery, comprising a housing, a battery cell disposed in the housing, and a top cover structure as described in any one of the above items for sealing an opening of the housing;

[0031] The connecting block is connected to the first tab of the battery cell;

[0032] The first electrode tab has the same polarity as the first electrode column.

[0033] In the above technical solution, by adopting a top cover structure, the number of separate components that need to be set up is reduced, the process is simplified, the production efficiency is improved, and it is easier to control the quality of each component and the overall quality of the battery; reducing independent components and reducing the resistance of the current transmission path makes the internal resistance of the battery itself lower, thereby improving the working efficiency of the battery.

[0034] In a specific embodiment, there are multiple battery cells, and at least two battery cells are arranged in the width direction of the battery;

[0035] The connecting blocks correspond one-to-one to the first tabs of the batteries.

[0036] In the above technical solution, compared with the existing battery structure, the battery cells are stacked in the shell only in the thickness direction of the battery, which can increase the energy density of the battery; and the first pole and the connecting block are directly connected to the first pole lug through the connecting block, and only the adapter plate needs to be set for the second pole. Compared with the situation where the first pole and the second pole need to be respectively provided with corresponding adapter structures, the problem of interference between the adapter plates corresponding to poles of different polarities is reduced; during the design process, only the shape of the adapter plate corresponding to the second pole needs to be considered, and the arrangement of the battery cells needs to be adjusted to reduce the size of the adapter plate, and then the position of the connecting block can be set corresponding to the first pole lug, which makes the overall design and subsequent production and assembly more convenient.

[0037] In a specific embodiment, the area of ​​the surface of the connecting block connected to the first electrode tab is S1;

[0038] The area of ​​the surface of the first tab connected to the connection block is S2;

[0039] S1 and S2 satisfy: S1 / S2≥0.25.

[0040] In the above technical solution, the stability of the connection between the connecting block and the first electrode is ensured; the situation where the connection area is too small is avoided, that is, the flow area between the connecting block and the first electrode is large enough to maintain a sufficiently large current transmission efficiency and improve the working efficiency of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG1 is a schematic diagram of the overall structure of a battery provided in an embodiment of the present application;

[0042] FIG2 is a schematic diagram of a top cover structure provided in an embodiment of the present application;

[0043] FIG3 is a cross-sectional schematic diagram of a top cover structure provided in an embodiment of the present application;

[0044] FIG4 is a schematic diagram of the relative positions of the connection block and the second pole provided in an embodiment of the present application.

[0045] Explanation of the accompanying reference numerals: 1. Shell; 2. Battery cell; 21. First pole tab; 22. Second pole tab; 3. Cover plate; 31. First surface; 32. Second surface; 4. First pole; 5. Second pole; 6. Connecting block; 7. Adapter; 8. Plastic plate; 81. Avoidance hole. DETAILED DESCRIPTION

[0046] The present invention will be further described in detail below through the following examples, through which the features and advantages of the present invention will become more clear and distinct.

[0047] The word "exemplary" is used exclusively herein to mean "serving as an example, example, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0048] In addition, the technical features involved in different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0049] To facilitate understanding of the top cover structure and battery provided in the embodiments of the present application, the structure of the battery is first briefly described. The battery includes a shell, a battery cell arranged in the shell, and a top cover structure for sealing the shell opening. The top cover structure includes a cover plate, a pole arranged on the cover plate and insulated from the cover plate, and the pole column and the pole ear of the battery cell are electrically connected through a connecting piece to form an internal passage of the battery structure. This battery structure includes many independent components (poles, connecting links, insulating and sealing structures between poles and cover plates, etc.), which causes the production and assembly process of battery components to be more complicated, and the processing efficiency is low. In addition, without considering the influence of material and processing error, the resistance at the connection between different components is greater than the resistance of the single component itself. The more components on the current transmission path, the greater the internal resistance of the battery itself, which reduces the working efficiency of the battery.

[0050] The present invention provides a top cover structure and battery that simplifies the battery structure, simplifies the production and assembly processes of battery components, facilitates battery quality control, reduces the battery's internal resistance, and improves battery efficiency. The following describes this in detail with reference to specific figures and embodiments.

[0051] Referring to Figure 1, which shows a schematic structural diagram of a battery provided in an embodiment of the present application, the battery provided in an embodiment of the present application comprises a housing 1, a battery cell 2 disposed within the housing 1, and a top cover structure for sealing an opening of the housing 1. The battery cell 2 is located within the housing 1 and is fixedly connected to the housing 1, illustratively by bonding with structural adhesive. The top cover structure is fixedly connected to the housing 1 by various fixing methods, such as welding, bonding, and clamping.

[0052] Referring to Figures 2 and 3, the top cover structure includes a cover plate 3, a first pole 4, a second pole 5, and a connecting block 6. The cover plate 3 has a first surface 31 and a second surface 32. The first surface 31 and the second surface 32 are two surfaces facing each other in the thickness direction of the cover plate 3, and the second surface 32 is the side of the cover plate 3 facing the battery cell 2. The first pole 4 is located on the first surface 31 of the cover plate 3 and is fixedly connected to the cover plate 3. The connecting block 6 is located on the second surface 32 of the cover plate 3 and is also fixedly connected to the cover plate 3. The second pole 5 extends through the first and second surfaces 31 and 32 of the cover plate 3, is fixed relative to the cover plate 3, and is insulated from the cover plate 3. The battery cell 2 has a first tab 21 and a second tab. The connecting block 6 is connected to the first tab 21 of the battery cell 2, and the second pole 5 is connected to the second tab 22 of the battery cell 2. The first pole 4 has the same polarity as the first tab 21, and the second pole 5 has the same polarity as the second tab 22.

[0053] The connecting block 6 abuts against the first pole ear 21 of the battery cell 2, and an electrical connection between the two is achieved by welding; the second pole 5 is located at one end of the second surface 32 of the cover plate 3 and is connected to the adapter plate 7, and the second pole ear 22 is electrically connected to the second pole 5 through the adapter plate 7; illustratively, the second pole 5, the adapter plate 7 and the second pole ear 22 of the battery cell 2 are fixedly connected by welding to achieve electrical connection between the three.

[0054] Among them, the connection method between the second pole 5 and the cover plate 3, as well as the insulation treatment between the second pole 5 and the cover plate 3, can refer to the existing battery structure, the connection structure between the pole and the cover plate 3 and the insulation treatment method, and this part will not be repeated in the embodiment of the present application.

[0055] Through the provided top cover structure, the first terminal 4 is fixedly connected to the cover plate 3. A connecting block 6 is provided on the second surface 32 of the cover plate 3, forming a raised structure protruding from the second surface 32. The connecting block 6 is electrically connected to the first terminal tab 21 of the battery cell 2. This reduces the number of required independent components, simplifies the component production and assembly processes, and improves work efficiency. The reduced number of components also makes it easier to monitor the quality of each component and facilitate overall battery quality control. In addition, the direct connection between the connecting block 6 and the first terminal tab 21 reduces the resistance of the transmission path compared to the existing connection method via a connecting piece. In other words, the internal resistance of the battery itself is reduced, thereby improving the battery's operating efficiency.

[0056] For example, the first pole 4 is a positive pole. In this case, the cover plate 3 is made of aluminum or an aluminum alloy. Of course, in other embodiments, the first pole 4 can also be set as a negative pole. Correspondingly, the cover plate 3 is made of copper or a copper alloy. In the specific design, the specific polarity of the first pole 4 can be determined according to actual needs. In the embodiment of this application, the first pole 4 is used as a positive pole as an example for description.

[0057] The first pole column 4 and the cover plate 3 can be fixed by welding, or the first pole column 4 and the cover plate 3 can be integrally formed. In the embodiment of the present application, the first pole column 4 and the cover plate 3 are integrally formed. The connecting block 6 is also integrally formed with the cover plate 3. The connecting block 6 can not only be set as a solid block structure, but also the connecting block 6 can be set as a hollow shell structure formed by stamping the cover plate 3; of course, in other embodiments, the connecting block 6 can also be welded and fixed to the cover plate 3.

[0058] In addition, the top cover structure further includes a plastic plate 8. The plastic plate 8 is arranged on one side of the second surface 32 of the cover plate 3 and is adhered to the second surface 32 of the cover plate 3. The plastic plate 8 is fixedly connected to the cover plate 3 and / or the housing 1; an avoidance hole 81 for the second pole column 5 and the connecting block 6 to pass through is formed on the plastic plate 8. The arranged plastic plate 8 separates the cover plate 3 from the battery cell 2. In the case where the cover plate 3 is subjected to an external impact, a certain buffering effect can also be achieved through the plastic plate 8; in addition, the plastic plate 8 is an insulating structure (determined by the nature of the plastic material itself), avoiding the problem of short circuit when the cover plate 3 directly abuts against the battery cell 2, and improving the stability of the battery.

[0059] In the state where the top cover structure is assembled with the housing 1, the connecting block 6 abuts against the first pole ear 21 on the battery cell 2, and the electrical connection between the two is realized by welding subsequently. Referring to FIGS. 3 and 4, the connecting block 6 is arranged to pass through the avoidance hole 81 and extend to the side of the plastic plate 8背离盖板3 (away from the cover plate 3). The distance between the surface of the connecting block 6背离盖板3 (away from the cover plate 3) and the surface of the plastic plate 8背离盖板3 (away from the cover plate 3) is a, and a satisfies: 0 < a ≤ 5 mm; and the position of the connecting block 6 corresponds to the position of the first pole ear 21. In this way, the connection between the connecting block 6 and the first pole ear 21 can be realized more conveniently.

[0060] The connecting block 6 is arranged to protrude from the plastic plate 8 by a sufficient distance. Compared with the situation where the surface of the connecting block 6 facing the battery cell 2 is flush with the surface of the plastic plate 8背离盖板3 (away from the cover plate 3) or even the surface of the plastic plate 8背离盖板3 (away from the cover plate 3) faces the cover plate 3 side, it is more convenient to connect the connecting block 6 and the first pole ear 21. At the same time, the value of the distance a is limited not to exceed 5 mm to avoid the problem of leaving too large a gap between the plastic plate 8 and the battery cell 2 after the battery is assembled due to too large a distance, reducing the problems of space waste and reduction of the energy density of the battery.

[0061] The second pole column 5 also passes through the avoidance hole 81 to the side of the plastic plate 8背离盖板3 (away from the cover plate 3). The adapter plate 7 is connected to one end of the second pole column 5 passing through the avoidance hole 81. In the state where the adapter plate 7 is connected to the second pole column 5, the distance between the surface of the adapter plate 7背离盖板3 (away from the cover plate 3) and the surface of the plastic plate 8背离盖板3 (away from the cover plate 3) is b, and a = b.

[0062] It should be made clear here that the way in which the second pole 5 is connected to the second pole 5 of the battery cell 2 through the adapter 7 is a design method commonly adopted in existing battery structures. Therefore, the dimensions of the second pole 5 and the adapter 7, that is, the value of the spacing b, can be determined by personnel in this field based on existing design methods.

[0063] When designing the top cover structure, the size of the connecting block 6, that is, the value of the spacing a, is determined according to the value of the spacing b, so that the two remain the same. During the battery assembly process, the top cover structure blocks the opening of the shell 1, so that the connecting block 6 and the adapter plate 7 are synchronously abutted against their respective corresponding first pole lugs 21 and second pole lugs 22, and then fixedly connected by welding. This can ensure the synchronization of the connection with the first pole lug 21 and the second pole lug 22 during the assembly process, facilitate the assembly operation, and improve production efficiency.

[0064] It should also be noted that in actual production, if the value of spacing b is greater than 5 mm, the size of the connecting block 6 can be designed according to actual needs, that is, the value of spacing a can also be set to be greater than 5 mm and remain the same as the value of spacing b to ensure that the subsequent welding of the two can be carried out synchronously and maintain high production efficiency.

[0065] The connecting block 6 is connected to the first pole tab 21. In order to ensure the stability of the connection and maintain a high current transmission efficiency, it is necessary to ensure that the connection area between the connecting block 6 and the first pole tab 21 is large enough. The area of ​​the surface of the connecting block 6 connected to the first pole tab 21 is S1, and the area of ​​the surface of the first pole tab 21 connected to the connecting block 6 is S2. S1 and S2 satisfy: S1 / S2≥0.25.

[0066] When connecting the connecting block 6 to the first pole tab 21, with the size of the first pole tab 21 determined, ensure that the size of the connecting block 6 is large enough, S1 is not less than 1 / 4 of S2, to ensure the stability of the connection between the connecting block 6 and the first pole tab 21; avoid the situation where the connection area is too small, that is, the flow area between the connecting block 6 and the first pole tab 21 is large enough to maintain a sufficiently large current transmission efficiency and improve the working efficiency of the battery.

[0067] Furthermore, referring to Figure 1 , multiple battery cells 2 are provided, and at least two battery cells 2 are arranged in the width direction of the battery. Accordingly, multiple connection blocks 6 are provided, and the multiple connection blocks 6 correspond one-to-one with the first tabs 21 of the multiple batteries. In this embodiment of the present application, an example of two battery cells 2 arranged in the width direction of the battery is used for illustration.

[0068] The width direction of the battery refers to the direction parallel to the large surface of the battery cell 2 and perpendicular to the height direction of the battery; of course, in this case, multiple battery cells 2 can also be stacked and arranged in the thickness direction of the battery at the same time.

[0069] Compared with the existing battery structure, the battery cells 2 are stacked only in the thickness direction of the battery in the shell 1, which can increase the energy density of the battery; and in conjunction with the first pole 4 and the connecting block 6 integrally formed with the cover plate 3, it is directly connected to the first pole ear 21 through the connecting block 6, and only the adapter plate 7 needs to be set for the second pole 5. Compared with the situation where corresponding connecting plates need to be set respectively for the first pole 4 and the second pole 5, the problem of interference between the connecting plates corresponding to poles of different polarities is reduced, and it is more convenient to set the adapter plate 7 to connect the second pole 5 and the second pole ear 22.

[0070] During the design stage, it is only necessary to consider the size of the adapter 7 connected to the second pole 5. By adjusting the position of the battery cell 2, the size of the adapter 7 connected to the second pole ear 22 can be made as small as possible, which can save materials and reduce the internal resistance of the battery. The position of the connecting block 6 can then be designed according to the position of the first pole ear 21, making the overall design process and subsequent production and assembly more convenient.

[0071] Taking two battery cells 2 arranged in the width direction of the battery as an example, the second pole 5 of the battery cell 2 is located in the middle of the battery, and correspondingly, the adapter plate 7 is located in the middle of the battery to realize the connection between the second pole 5 and multiple (four in total as shown in the figure) second pole ears 22; the position of the connecting block 6 is determined according to the size of the battery cell 2 and other data during production, and is distributed on the outside of the battery structure. In this case, since there is no need to set a connecting plate for the first pole 4, it can be more convenient to realize the connection between the first pole 4 and multiple first pole ears 21.

[0072] In the description of this application, it should be noted that the terms "upper", "lower", "inside", "outside", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships in the working state of this application. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on this application.

[0073] In the description of this application, it should be noted that, unless otherwise specified or limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0074] The present application has been described above in conjunction with preferred embodiments, but these embodiments are merely exemplary and serve only as an illustrative example. On this basis, various replacements and improvements can be made to the present application, all of which fall within the scope of protection of the present application.

Claims

1. A top cover structure, characterized in that: include, A cover plate, wherein the cover plate is made of a conductive material; A first pole, located on the first surface of the cover plate and fixedly connected to the cover plate; a second pole, passing through the first surface and the second surface of the cover plate and insulated from the cover plate; a connecting block, located on the second surface of the cover plate and fixedly connected to the cover plate; The connecting block is used to connect to the first tab of the battery cell; The first surface and the second surface are two surfaces facing away from each other in the thickness direction of the cover plate, and the second surface is a side of the cover plate facing the battery cell.

2. The top cover structure according to claim 1, characterized in that: The first pole is a positive pole, and the cover is made of aluminum or an aluminum alloy.

3. The top cover structure according to claim 1, characterized in that: The first pole is a negative pole, and the cover is made of copper or a copper alloy.

4. The top cover structure according to any one of claims 1 to 3, characterized in that: The first pole and the connecting block are integrally formed with the cover plate.

5. The top cover structure according to claim 1, characterized in that: It also includes a plastic plate, which is attached to the second surface of the cover plate. The plastic plate is provided with an avoidance hole for the second pole and the connecting block to pass through.

6. The top cover structure according to claim 5, characterized in that: The connecting block extends through the avoidance hole to a side of the plastic plate facing away from the cover plate; The distance between the surface of the connecting block facing away from the cover plate and the surface of the plastic plate facing away from the cover plate is a, and a satisfies: <a≤5mm。 7. The roof structure according to claim 1 or 6, characterized in that: The second pole extends through the avoidance hole to the side of the plastic plate facing away from the cover plate; One end of the second pole passing through the avoidance hole is connected to a transfer plate; The distance between the side surface of the adapter plate facing away from the cover plate and the surface of the plastic plate facing away from the cover plate is b; a and b satisfy: a=b.

8. A battery, characterized in that: comprising a housing, a battery cell disposed in the housing, and a top cover structure according to any one of claims 1 to 7 for sealing an opening of the housing; The connecting block is connected to the first tab of the battery cell; The first electrode tab has the same polarity as the first electrode column.

9. The battery according to claim 8, characterized in that There are multiple battery cells, and at least two of the battery cells are arranged in the width direction of the battery; The connection blocks correspond one-to-one to the first tabs of the batteries.

10. The battery according to claim 8, characterized in that The area of the surface of the connecting block connected to the first tab is S1; The area of the surface of the first tab connected to the connection block is S2; S1 and S2 satisfy: S1 / S2≥0.25.

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