Battery cell cover plate assembly, battery cell, and battery pack

Abstract

The utility model relates to battery technology field discloses the electric core cover plate subassembly, electric core and battery package, wherein, the electric core cover plate subassembly, include: cover plate body, pole body and pole bottom plate, cover plate body is equipped with mounting hole, pole body is inserted in the mounting hole, and pole body includes the main part and the connecting body that are connected, the main part is non -cylinder, and the size of main part is greater than in the cover plate body width direction's size in the length direction of cover plate body, and the connecting hole is seted up on the pole bottom plate, and the connecting hole in the bottom plate is worn to the connecting body, and with pole bottom plate welds. The utility model connects the connecting body on the main part of non -cylinder structure, and the connection of pole body and pole bottom plate is realized through the welding of connecting body and the connecting hole of pole bottom plate, and the stress is even in the welding process, can reduce stress concentration, and it is convenient to press -pack welding forming, and welding stability is better, and it is favorable to realize the stable connection of pole body and pole bottom plate.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a cell cover assembly, a cell, and a battery pack. Background Technology

[0002] With the continuous development of technology, users have increasingly higher requirements for new energy batteries. In order to improve the fast charging capability of the battery cell, it is necessary to improve the current carrying capacity of the terminal. In thin battery cells, in order to ensure the current carrying capacity of the terminal, the terminal body can be made into a non-cylindrical structure and then connected to the terminal base plate.

[0003] However, due to the shape of the non-cylindrical pole body, there are problems such as uneven contact surface and uneven pressure distribution, which makes it difficult to press-fit the pole body. The pole body is difficult to press-fit and weld to the pole base plate, and it is also easy to produce defects in welding, resulting in poor connection stability between the pole body and the pole base plate. Utility Model Content

[0004] In view of this, the present invention provides a cell cover plate assembly, a cell, and a battery pack to solve the problem that when non-cylindrical electrode body and electrode base plate are press-fitted and welded, there are difficulties in press-fitting, which easily leads to welding defects and results in poor connection stability between the electrode body and electrode base plate.

[0005] In a first aspect, this utility model provides a battery cell cover assembly, comprising:

[0006] The cover plate body is provided with mounting holes;

[0007] The electrode body is inserted into the mounting hole. The electrode body includes a main body and a connecting body connected together. The main body is non-cylindrical. The dimension of the main body in the length direction of the cover plate body is greater than the dimension in the width direction of the cover plate body.

[0008] The electrode base plate has a connection hole, and the connector is inserted into the connection hole and welded to the electrode base plate.

[0009] Beneficial effects: The main body of the electrode post of this utility model adopts a non-cylindrical structure. The length dimension of the main body in the cover plate body is larger than the width dimension of the cover plate body, which increases the current-carrying area of ​​the main body and improves the current-carrying capacity, thereby enhancing the fast-charging capability and capacity of the battery cell. A connector is provided on the non-cylindrical main body and welded to the connection hole of the electrode post base plate, replacing the direct welding of the non-cylindrical main body to the electrode post base plate. This results in uniform stress distribution during press welding, reduces stress concentration, facilitates press welding formation, and improves welding stability. This facilitates a stable connection between the electrode post body and the electrode post base plate and also reduces the risks of electrode post body breakage, warping, and material expansion.

[0010] In one optional embodiment, the connector is a columnar structure, which includes a cylindrical structure and a prism structure.

[0011] Beneficial effects: The connector adopts a columnar structure, which has axisymmetric characteristics. During press fitting, the force is evenly distributed, which can avoid local stress concentration caused by uneven force distribution, reduce deformation, and further improve the connection stability between the pole body and the pole base plate.

[0012] In one optional embodiment, the size of the main body is W1 in the width direction of the cover plate body, satisfying 3mm≤W1≤15mm.

[0013] Beneficial effects: By limiting the dimensions of the main body in the width direction of the cover plate, that is, the width of the main body, the flow capacity of the main body can be ensured. If the width of the main body is too small, the flow area is small and the flow capacity is insufficient. If the size of the main body is too large, it occupies a large space and wastes materials.

[0014] In one alternative embodiment, in the width direction of the cover plate body, the size W1 of the main body is greater than or equal to the size W2 of the connecting body.

[0015] Beneficial effects: Since the width of the main body is greater than or equal to the width of the connecting body, a stepped surface can be formed between the main body and the connecting body. This stepped surface abuts against the pole base plate, which is used to limit and support the main body, and can also prevent the formation of gaps between the pole base plate and the connecting body, thus ensuring sealing performance.

[0016] In one optional embodiment, the connector is a cylindrical structure with a radius of r, satisfying 1.25mm≤r≤W1 / 2.

[0017] Beneficial effect: By limiting the radius of the connecting body of the cylindrical structure, it is easier to form the connecting body. If the radius of the connecting body is too small, it will be difficult to process and form.

[0018] In one alternative embodiment, the main body and the connector are integrally formed.

[0019] Beneficial effects: The main body and connecting body are molded as one piece, which facilitates installation and assembly.

[0020] In one optional embodiment, the cell cover assembly further includes an upper insulating member and a riveting block. The cover body has a first surface and a second surface disposed opposite to each other along the thickness direction. The riveting block is connected to the main body and is disposed corresponding to the first surface. The upper insulating member is sandwiched between the riveting block and the cover body.

[0021] Beneficial effects: The upper insulating component effectively isolates the electrode post body from the cover plate body, avoiding risks such as short circuits and leakage in the electrode post body. The main body is fixed by the riveting blocks, which can resist external forces such as vibration and impact, improving the installation stability of the electrode post body.

[0022] In one optional embodiment, the cell cover assembly further includes a sealing ring and a lower insulating member, the lower insulating member being attached to the second surface, the electrode base plate being disposed on the side of the lower insulating member away from the second surface, and the sealing ring being sleeved on the outer peripheral wall of the main body and sandwiched between the electrode base plate and the lower insulating member and between the main body and the cover body.

[0023] Beneficial effects: By fitting a sealing ring on the outer periphery of the main body, a sealing effect can be achieved, preventing electrolyte leakage inside the battery cell and preventing foreign objects from entering the battery cell. In addition, the sealing ring also has good insulation properties.

[0024] Secondly, this utility model also provides a battery cell, comprising:

[0025] The housing has an opening at at least one end;

[0026] In the aforementioned cell cover assembly, the cover body is disposed over the opening and connected to the housing.

[0027] Beneficial effects: The battery cell of this utility model adopts a non-cylindrical structure for the main body of the electrode post. The length dimension of the main body in the cover plate body is larger than the width dimension of the cover plate body, which increases the current-carrying area of ​​the main body and improves the current-carrying capacity, thereby enhancing the fast-charging capability and capacity of the battery cell. A connector is set on the non-cylindrical main body and welded to the connection hole of the electrode post base plate, replacing the direct welding of the non-cylindrical main body to the electrode post base plate. This results in uniform stress distribution during press welding, reduces stress concentration, facilitates press welding and forming, and improves welding stability. This facilitates a stable connection between the electrode post body and the electrode post base plate and also reduces the risk of breakage, warping, and material expansion of the electrode post body.

[0028] Thirdly, the present invention also provides a battery pack, comprising: at least one of the above-mentioned battery cells.

[0029] Beneficial effects: Since the battery pack includes battery cells, it has the same effects as the battery cells, which will not be elaborated here. Attached Figure Description

[0030] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of a battery cell cover assembly according to an embodiment of the present utility model;

[0032] Figure 2 for Figure 1 Exploded view;

[0033] Figure 3 This is a bottom view of a battery cell cover assembly according to an embodiment of the present utility model;

[0034] Figure 4 This is a schematic diagram of the electrode post of a battery cell cover assembly according to an embodiment of the present utility model;

[0035] Figure 5 This is a schematic diagram of the first type of main body and connecting body of a battery cell cover assembly according to an embodiment of the present utility model;

[0036] Figure 6 This is a schematic diagram of a second type of main body and connector of a battery cell cover assembly according to an embodiment of the present utility model;

[0037] Figure 7 This is a schematic diagram of a third type of main body and connector of a battery cell cover assembly according to an embodiment of the present utility model;

[0038] Figure 8 This is a schematic diagram of the fourth main body and connecting body of a battery cell cover assembly according to an embodiment of the present utility model.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Cover plate body; 101. Mounting hole; 2. Pole post body; 201. Main body; 202. Connector; 3. Pole post base plate; 301. Connecting hole; 4. Upper insulating component; 5. Riveting block; 6. Sealing ring; 7. Lower insulating component. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0042] The following is combined Figures 1 to 8 The following describes embodiments of the present invention.

[0043] According to embodiments of the present invention, on the one hand, such as Figure 1 and Figure 2 As shown, a battery cell cover assembly is provided, mainly including: a cover body 1, a terminal body 2, and a terminal base plate 3. The cover body 1 has a mounting hole 101. The terminal body 2 is inserted into the mounting hole 101. The terminal body 2 includes a main body 201 and a connecting body 202 connected together. The main body 201 is non-cylindrical, and the dimension of the main body 201 in the length direction of the cover body 1 is larger than the dimension in the width direction of the cover body 1. The terminal base plate 3 has a connecting hole 301, and the connecting body 202 passes through the connecting hole 301 and is welded to the terminal base plate 3.

[0044] Therefore, the battery cell provided in this embodiment of the present invention has a non-cylindrical structure for the main body 201 of the electrode body 2. The length dimension of the main body 201 in the cover plate body 1 is larger than the width dimension of the cover plate body 1, which increases the current-carrying area of ​​the main body 201 and improves the current-carrying capacity, thereby enhancing the fast-charging capability and capacity of the battery cell. A connector 202 is provided on the non-cylindrical main body 201, and the connector 202 is welded to the connection hole 301 of the electrode base plate 3, replacing the non-cylindrical main body 302 which is directly welded to the electrode base plate 3. The pressure is evenly distributed during press welding, which can reduce stress concentration, facilitate press welding and forming, and improve welding stability. This facilitates the stable connection between the electrode body 2 and the electrode base plate 3, and also reduces the risk of breakage, warping, and material expansion of the electrode body 2.

[0045] Specifically, the connector 202 is fixed to one end of the main body 201 near the pole base plate 3. After passing through the connecting hole 301, the connector 202 is fixed by butt welding through the press-fit pole base plate 3. The shape of the connecting hole 301 corresponds to the connector 202. The connecting hole 301 can be selected as a blind hole or a through hole as needed. Other conventional structures such as explosion-proof valves can also be installed on the cover plate body 1 as needed.

[0046] It should be noted that the cell cover assembly in this embodiment is applied to a blade battery. The cover body 1 of the blade battery has a large aspect ratio, that is, the length of the cover body 1 is large and the width is small. Currently, the industry has increasingly higher requirements for the charge and discharge rate of batteries, which requires an increase in the current carrying capacity of the terminals, that is, an increase in the cross-sectional area of ​​the terminals. In the prior art, the cross-section of the terminals is usually circular. Since the width of the cover body 1 of the blade battery is small, it is not convenient to increase the diameter of the circle. Therefore, the prior art usually sets two cylindrical terminals to increase the current carrying capacity. This setting leads to a complicated assembly process and low assembly efficiency of the cover assembly. In this embodiment, the dimension of the main body 201 along the length direction of the cover body 1 is increased, which can improve the current carrying capacity of the terminal body 2 without increasing the number of terminals, thus ensuring assembly efficiency.

[0047] It should be noted that the non-cylindrical main body 201 needs to be as large as possible in the length direction of the cover plate body 1. Under the premise that the width of the cover plate body 1 is limited, the cross-sectional area of ​​the main body 201 should also be increased as much as possible to improve the flow area of ​​the main body 201, thereby having good flow capacity.

[0048] Non-cylinders include, but are not limited to, elliptical cylinders, racetrack-shaped cylinders, rectangular cylinders, and irregular cylinders. That is, the cross-section of the main body 201 includes, but is not limited to, elliptical cross-sections, racetrack-shaped cross-sections, rectangular cross-sections, and irregular cross-sections.

[0049] For example, the main body 201 is an elliptical cylinder, that is, the cross-section of the main body 201 is an elliptical cross-section, such as... Figure 6 As shown, the elliptical cylinder body 201 has a larger radius of curvature along its major axis and a smaller radius of curvature along its minor axis. If it is directly press-fitted and welded to the pole base plate 3, uneven stress is likely to occur, leading to excessive local stress and thus cracks, eventually resulting in fracture defects. Furthermore, the major and minor axes of the elliptical cylinder dissipate heat at different rates—the major axis dissipates heat faster than the minor axis—which can easily lead to uneven shrinkage and warping defects. When the elliptical cylinder body 201 is directly press-fitted to the connecting hole 301 of the pole base plate 3, the body 201 is easily compressed and, after long-term use, is prone to bulging, resulting in a material bulging defect.

[0050] In other embodiments, the main body 201 can also be a racetrack-shaped column, that is, the cross-section of the main body 201 is a racetrack-shaped cross-section, such as... Figure 5 As shown; or, the main body 201 can also be a rectangular prism, that is, the cross-section of the main body 201 is a rectangular cross-section, as shown. Figure 7 As shown; or, the main body 201 can also be an irregular column, that is, the cross-section of the main body 201 is an irregular cross-section, such as... Figure 8 As shown.

[0051] To facilitate press-fit welding and overcome welding defects, in one embodiment, the connector 202 is a columnar structure, including cylindrical and prismatic structures. The columnar structure has axisymmetric characteristics, ensuring uniform stress distribution during press-fitting. This avoids localized stress concentration caused by uneven stress distribution, reduces deformation, and further enhances the connection stability between the pole body 2 and the pole base plate 3.

[0052] In this embodiment of the utility model, the symmetrical connecting body 202 is welded to the pole base plate 3, resulting in uniform pressure distribution and heat dissipation, which is conducive to press-fitting and welding and can reduce defects such as breakage, warping, and material expansion of the pole body 2.

[0053] In one embodiment, such as Figure 1 and Figure 5 As shown, in the width direction of the cover plate body 1, the dimension W1 of the main body 201 satisfies 3mm ≤ W1 ≤ 15mm. For example, the dimension W1 of the main body 201 can be 3mm, 5mm, 10mm, 15mm, etc. The main body 201 extends along the length direction of the cover plate body 1, that is, the length direction of the main body 201 is consistent with the length direction of the cover plate body 1, and the width direction of the main body 201 is consistent with the width direction of the cover plate body 1, which facilitates the installation of the main body 201. By limiting the dimension of the main body 201 in the width direction of the cover plate body 1, that is, the width of the main body 201, a suitable flow area can be formed to ensure the flow capacity of the main body 201. If the dimension of the main body 201 is too small, the flow area will be small and the flow capacity will be insufficient; if the dimension of the main body 201 is too large, it will occupy a large space and waste materials.

[0054] Specifically, the length direction of the cover plate body 1 is as follows: Figure 3 As indicated by arrow L in the diagram, the width direction of the cover body 1 is as follows: Figure 3 As indicated by the arrow W in the diagram.

[0055] In one embodiment, in the width direction of the cover plate body 1, the dimension W1 of the main body 201 is greater than or equal to the dimension W2 of the connecting body 202. Since the width dimension of the main body 201 is greater than or equal to the width dimension W2 of the connecting body 202, a stepped surface can be formed between the main body 201 and the connecting body 202. This stepped surface abuts against the pole post base plate 3, serving to limit and support the main body 201, and also improving sealing. If the width dimension W2 of the connecting body 202 is greater than the width dimension W1 of the main body 201, a gap can easily form between the top of the pole post base plate 3 and the connecting body 202 after the connecting body 202 is assembled with the pole post base plate 3, thereby posing a risk of abnormal airtightness.

[0056] Furthermore, since the main body 201 extends along the length of the cover plate body 1 and the connecting body 202 is a cylindrical structure, the size of the main body 201 is greater than or equal to the size of the connecting body 202 along the length of the cover plate body 1.

[0057] Furthermore, in one embodiment, such as Figure 4 and Figure 5 As shown, the connector 202 is a cylindrical structure with a radius of r, satisfying 1.25mm ≤ r ≤ W1 / 2. For example, when the size W1 of the main body 201 is 3mm, the radius r of the connector 202 can be 1.25mm, 1.35mm, 1.5mm, etc. By limiting the radius of the cylindrical connector 202, it is easier to form the connector 202. If the radius of the connector 202 is too small, it will be difficult to process and form.

[0058] Furthermore, in the case where the connector 202 is a cylindrical structure, such as Figure 3 As shown, the connecting hole 301 on the pole base plate 3 is set as a round hole.

[0059] It should be noted that the present invention does not limit the connection structure between the main body 201 and the connector 202, and any existing connection structure can be selected as needed.

[0060] In one embodiment, such as Figure 4 As shown, the main body 201 and the connector 202 are integrally formed. This integral forming of the main body 201 and the connector 202 facilitates installation and assembly.

[0061] In one embodiment, such as Figure 1 and Figure 2 As shown, the cell cover assembly also includes an upper insulating member 4 and a riveting block 5. The cover body 1 has a first surface and a second surface that are arranged opposite each other along the thickness direction. The riveting block 5 is connected to the main body 201 and is arranged corresponding to the first surface. The upper insulating member 4 is sandwiched between the riveting block 5 and the cover body 1. The upper insulating member 4 can effectively isolate the electrode post body 2 and the cover body 1, avoiding the risk of short circuits and leakage in the electrode post body 2. By fixing the main body 201 with the riveting block 5, it can resist external forces such as vibration and impact, improving the installation stability of the electrode post body 2.

[0062] It should be noted that after the cell cover assembly is installed with the cell housing, the first surface of the cover body 1 is located on the outer side, and the second surface is located on the inner side. In addition, the electrode base plate 3 is located on the inner side of the cover body 1, and the main body 201 needs to extend and partially protrude from the outer side of the cover body 1.

[0063] Specifically, the "inner" and "outer" directions in this embodiment of the utility model are as follows: Figure 1 As shown by the arrow.

[0064] Furthermore, in one embodiment, such as Figure 1 and Figure 2As shown, the cell cover assembly also includes a sealing ring 6 and a lower insulating member 7. The lower insulating member 7 is attached to the second surface, and the electrode base plate 3 is located on the side of the lower insulating member 7 away from the second surface. The sealing ring 6 is sleeved on the outer peripheral wall of the main body 201 and sandwiched between the electrode base plate 3 and the lower insulating member 7, as well as between the main body 201 and the cover body 1. By sleeved on the outer peripheral wall of the main body 201, a sealing function can be achieved, preventing electrolyte leakage from the cell and preventing foreign objects from entering the cell. In addition, the sealing ring 6 also has good insulation properties. The lower insulating member 7 is used for insulation between the cover body 1 and the cell electrode assembly.

[0065] It should be noted that the material of the cover plate body 1 is not limited in this embodiment of the utility model. Any existing material can be selected as needed, such as the cover plate body 1 being a plain aluminum plate.

[0066] According to an embodiment of the present invention, another aspect provides a battery cell, comprising: a housing and a battery cell cover assembly. The housing has an opening at at least one end, and an electrode assembly is disposed within the housing. The cover body 1 of the battery cell cover assembly covers the opening and is connected to the housing.

[0067] The battery cell provided in this embodiment of the utility model has a non-cylindrical structure for the main body 201 of the electrode body 2. The length dimension of the main body 201 in the cover plate body 1 is larger than its width dimension, which increases the current-carrying area of ​​the main body 201 and improves the current-carrying capacity, thereby enhancing the fast-charging capability and capacity of the battery cell. A connector 202 is provided on the non-cylindrical main body 201, and the connector 202 is welded to the connection hole 301 of the electrode base plate 3, replacing the non-cylindrical main body 302 which is directly welded to the electrode base plate 3. This results in uniform stress distribution during press welding, reduces stress concentration, facilitates press welding and forming, and improves welding stability. This facilitates a stable connection between the electrode body 2 and the electrode base plate 3 and reduces the risks of breakage, warping, and material expansion of the electrode body 2.

[0068] Specifically, a tab is provided on one side of the electrode assembly. The tab includes a positive tab and a negative tab. The electrode post body 2 includes a positive post and a negative post, wherein the positive tab is electrically connected to the positive post and the negative tab is electrically connected to the negative post. The connection between the cover plate body 1 and the housing can be selected from any existing connection structure as needed, and this embodiment of the utility model does not impose too many restrictions on this.

[0069] According to an embodiment of the present invention, in another aspect, a battery pack is also provided, comprising: at least one battery cell.

[0070] Since the battery pack includes battery cells and has the same effect as the battery cells, it will not be elaborated on here.

[0071] To achieve the basic functions of the battery pack, the battery pack in this embodiment may also include other necessary modules or components, such as a battery management system and a heat dissipation system. It should be noted that any suitable existing structure can be selected from the other necessary modules or components included in the battery pack. To clearly and concisely illustrate the technical solution provided in this embodiment, the above-mentioned parts will not be repeated here, and the accompanying drawings have also been simplified accordingly. However, it should be understood that the scope of the embodiments of this utility model is not limited thereto.

[0072] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cell cover assembly, characterized in that, include: The cover plate body is provided with mounting holes; The electrode body is inserted into the mounting hole. The electrode body includes a main body and a connecting body connected together. The main body is non-cylindrical. The dimension of the main body in the length direction of the cover plate body is greater than the dimension in the width direction of the cover plate body. The electrode base plate has a connection hole, and the connector passes through the connection hole and is welded to the electrode base plate.

2. The cell cover assembly according to claim 1, characterized in that, The connector is a columnar structure, which includes cylindrical structures and prism structures.

3. The cell cover assembly according to claim 2, characterized in that, In the width direction of the cover plate body, the size of the main body is W1, which satisfies 3mm≤W1≤15mm.

4. The cell cover assembly according to claim 3, characterized in that, In the width direction of the cover plate body, the size W1 of the main body is greater than or equal to the size W2 of the connecting body.

5. The cell cover assembly according to claim 4, characterized in that, The connector is a cylindrical structure with a radius of r, satisfying 1.25mm≤r≤W1 / 2.

6. The cell cover assembly according to any one of claims 1 to 5, characterized in that, The main body and the connector are integrally formed.

7. The cell cover assembly according to any one of claims 1 to 5, characterized in that, The cell cover assembly further includes an upper insulating member and a riveting block. The cover body has a first surface and a second surface that are disposed opposite to each other along the thickness direction. The riveting block is connected to the main body and is disposed corresponding to the first surface. The upper insulating member is sandwiched between the riveting block and the cover body.

8. The cell cover assembly according to claim 7, characterized in that, The cell cover assembly also includes a sealing ring and a lower insulating member. The lower insulating member is attached to the second surface, and the electrode base plate is located on the side of the lower insulating member away from the second surface. The sealing ring is sleeved on the outer peripheral wall of the main body and sandwiched between the electrode base plate and the lower insulating member, as well as between the main body and the cover body.

9. A battery cell, characterized in that, include: The housing has an opening at at least one end; The cell cover assembly according to any one of claims 1 to 8, wherein the cover body is disposed over the opening and connected to the housing.

10. A battery pack, characterized in that, include: At least one battery cell as described in claim 9.

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