Battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery cell and a battery pack, and the battery cell mainly comprises a shell, a cover plate and a pair of connecting sheets, the shell is provided with an opening, a plurality of pairs of pole groups arranged in the opening and a plurality of pairs of tabs in one-to-one correspondence with the pole groups; the cover plate covers the opening, the cover plate is provided with a through hole and a pair of poles, and the through hole is located between the pair of poles; the pair of connecting pieces are arranged on the pole groups and located on the inner side of the cover plate, one ends of the pair of connecting pieces are connected with the pole columns respectively, and the other opposite ends of the pair of connecting pieces extend to the through hole and are provided with a plurality of mounting grooves respectively; the tabs comprise bent parts formed by folding the end parts of the pole group, the bent parts penetrate through the mounting grooves and are connected with the connecting sheets, and the bent parts arranged in pairs are arranged in a back-to-back manner. According to the utility model, the bending times of the connecting sheet and the pole group are reduced, the pole column and the pole group are respectively positioned at two opposite ends of the connecting sheet, and the mounting thickness of the battery cell is reduced, so that the space utilization rate of the battery cell is improved, and the production efficiency of the battery cell is also improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery cell and a battery pack. Background Art

[0002] With the development of new energy technologies, battery packs are increasingly used in various new energy products.

[0003] At present, the battery cells of battery packs generally use connecting pieces to connect the pole columns and the pole ears. Both the connecting pieces and the pole ears need to be bent, and the connecting pieces, pole columns and pole ears are usually located on the same vertical plane. Therefore, a relatively large thickness space needs to be occupied, resulting in low space utilization rate of the battery cell. Summary of the Utility Model

[0004] In view of this, the utility model provides a battery cell and a battery pack to solve the problem that the connecting pieces and pole ears of the battery cell need to be bent and are arranged on the same vertical plane, occupying a relatively large thickness space and resulting in low space utilization rate of the battery cell.

[0005] In a first aspect, the utility model provides a battery cell, comprising:

[0006] A housing, provided with an opening, a plurality of pairs of pole groups arranged in the opening, and a plurality of pairs of pole ears corresponding to the pole groups one by one;

[0007] A cover plate, covering the opening, the cover plate being provided with a through hole and a pair of pole columns, the through hole being located between the pair of pole columns;

[0008] A pair of connecting pieces, arranged on the plurality of pole groups and located inside the cover plate, one ends of the pair of connecting pieces are respectively connected to the pair of pole columns, and the opposite ends both extend to the through hole and are respectively provided with a plurality of mounting grooves;

[0009] The pole ear includes a bent portion formed by converging the end of the pole group, the bent portion passes through the mounting groove and is connected to the connecting piece, and the paired bent portions are arranged back to back.

[0010] Advantageous Effects: For the battery cell provided by the utility model, the pole columns and the pole ears are connected by the connecting pieces. The pole columns and the pole ears are respectively located at opposite ends of the connecting piece. The connecting piece is arranged on the plurality of pole groups and located inside the cover plate, and there is no need to bend the connecting piece. The paired pole ears are arranged back to back and pass through one mounting groove, reducing the total number of bends of the connecting piece and the pole group. The pole columns and the pole groups are not on the same vertical plane, reducing the installation thickness of the battery cell, thereby improving the space utilization rate of the battery cell. Moreover, the processing procedures of the connecting piece and the pole group are also reduced, improving the production efficiency. Since both the pole columns and the connecting pieces are arranged on the cover plate, the pole columns and the connecting pieces can be installed on the housing together with the cover plate, which is also convenient for installation and disassembly.

[0011] In an alternative embodiment, the bent portion includes a first connecting section and a second connecting section perpendicularly connected to the first connecting section. A transition fillet is provided between the first connecting section and the second connecting section. A gap is left between the first connecting section and the pole group and the mounting groove of the connecting piece. The bottom surface of the second connecting section is attached to the top surface of the connecting piece along the width direction of the cover plate.

[0012] Advantageous effects: The first connecting section is used to connect the pole group. A gap is left between the first connecting section and the connecting piece, which can prevent the connecting piece from tearing the pole ear. The pole ears are arranged in pairs, and the bottom surface of the second connecting section is attached to the top surface of the connecting piece along the width direction of the cover plate, which can save the installation space in the width direction of the cover plate, thereby reducing the width of the through hole to ensure the structural strength of the cover plate.

[0013] In an alternative embodiment, the height H of the second connecting section relative to the pole group is 1.5 mm to 5 mm.

[0014] Advantageous effects: By setting the height of the second connecting section relative to the pole group, the space of the battery cell in the height direction of the pole group can be saved to the greatest extent while ensuring the strength and reliability of the second connecting section, improving the space utilization rate of the battery cell.

[0015] In an alternative embodiment, the connection part of the first connecting section and the pole group deviates to one side of the pole group, and the offset W ≤ 1 / 2T1, where T1 is the thickness of the pole group and T1 is 6 mm to 30 mm.

[0016] Advantageous effects: By setting the offset and limiting the offset size, the flatness of the end surface of the second connecting section after folding can be ensured, so as to omit the pole ear die-cutting process, reduce the use cost and improve the production efficiency.

[0017] In an alternative embodiment, a converging inclined surface is formed at one end of the pole group connected to the first connecting section, and the height h of the converging inclined surface is 0.2 mm to 3.5 mm.

[0018] Advantageous effects: The height of the converging inclined surface is determined by the thickness of the pole group. Setting the converging inclined surface can compact the pole ears after folding, so that the pole group has a certain load-bearing capacity.

[0019] In an alternative embodiment, the thickness T2 of the second connecting section is 0.1 mm to 2.5 mm.

[0020] Advantageous effects: By limiting the thickness of the second connecting section, the space in the height direction of the pole group can be further saved, improving the space utilization rate of the battery cell.

[0021] In an alternative embodiment, the radius R of the transition fillet between the first connecting section and the second connecting section is 0.1 mm to 0.3 mm.

[0022] Beneficial effects: By providing the transition fillet, the structural strength of the tab can be ensured, and tearing of the tab can be avoided.

[0023] In an alternative embodiment, the gap length D between the first connecting section and the mounting groove of the connecting piece satisfies D≥0.2 mm.

[0024] Beneficial effects: By defining the dimension of the gap length between the first connecting section and the connecting piece, space can be reserved to avoid the connecting piece tearing the tab.

[0025] In an alternative embodiment, the through hole is a rectangular through hole, the length direction of the rectangular through hole is the same as the length direction of the cover plate, and a pair of the pole columns are located on opposite sides in the length direction of the rectangular through hole.

[0026] Beneficial effects: The through hole being a rectangular through hole can adapt to the tab and the connecting piece. A pair of the pole columns are located on opposite sides in the length direction of the rectangular through hole, enabling the pole columns, the connecting piece, and the tab to be arranged in a staggered manner, avoiding the superposition of their thicknesses, and improving the space utilization rate of the battery cell.

[0027] In a second aspect, the present utility model further provides a battery pack, including: a plurality of the above-mentioned battery cells.

[0028] Beneficial effects: Since the battery pack includes the battery cells, it has the same effects as the battery cells, that is, the pole column and the tab are connected by the connecting piece, the pole column and the tab are respectively located at opposite ends of the connecting piece, the connecting piece is arranged on a plurality of pole groups and is located inside the cover plate, and there is no need to bend the connecting piece. The paired tabs are arranged back to back and pass through one mounting groove, reducing the total number of bends of the connecting piece and the pole groups. The pole column and the pole group are not in the same vertical plane, reducing the installation thickness of the battery cell, thereby improving the space utilization rate of the battery cell. Moreover, the processing procedures of the connecting piece and the pole group are also reduced, improving the production efficiency. Since both the pole column and the connecting piece are arranged on the cover plate, the pole column and the connecting piece can be installed on the housing together with the cover plate, which is also convenient for installation and disassembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0030] Figure 1Structural schematic diagram of a battery cell according to an embodiment of the present utility model;

[0031] Figure 2 is Figure 1 top view of;

[0032] Figure 3 is Figure 2 partial structural schematic diagram of the A-A cross-section in;

[0033] Figure 4 is Figure 2 B-B cross-sectional view in;

[0034] Figure 5 is Figure 4 magnified view at C in;

[0035] Figure 6 Partial structural schematic diagram of a battery cell before the ear is bent according to an embodiment of the present utility model;

[0036] Figure 7 Partial structural schematic diagram of a battery cell according to an embodiment of the present utility model;

[0037] Figure 8 Structural schematic diagram of the ear and the connecting piece of a battery cell before the ear is bent according to an embodiment of the present utility model;

[0038] Figure 9 Structural schematic diagram of the ear and the connecting piece of a battery cell after the ear is bent according to an embodiment of the present utility model.

[0039] Explanation of reference numerals:

[0040] 1. Housing; 2. Electrode group; 3. Ear; 301. Bending part; 3011. First connecting section; 3012. Second connecting section; 4. Cover plate; 401. Through hole; 5. Electrode post; 6. Connecting piece; 601. Installation groove; 7. Insulating washer; 8. Sealing ring; 9. Insulating plate; 10. Sealing plate; 11. Liquid injection hole. Detailed implementation manners

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

[0042] Next, in conjunction with Figures 1 to 9 , the embodiments of the present utility model will be described.

[0043] According to an embodiment of the present utility model, on the one hand, as Figures 1 to 4 shown, a battery cell is provided, mainly including: a housing 1, a cover plate 4, and a pair of connecting pieces 6. The housing 1 is provided with an opening, multiple pairs of electrode groups 2 disposed in the opening, and multiple pairs of electrode tabs 3 corresponding to the electrode groups 2 one by one. The cover plate 4 covers the opening. The cover plate 4 is provided with a through hole 401 and a pair of electrode posts 5. The through hole 401 is located between the pair of electrode posts 5. A pair of connecting pieces 6 are disposed on the multiple electrode groups 2 and are located inside the cover plate 4. One ends of the pair of connecting pieces 6 are respectively connected to the pair of electrode posts 5, and the opposite ends both extend to the through hole 401 and are respectively provided with a plurality of mounting grooves 601. The electrode tab 3 includes a bent portion 301 formed by converging the end of the electrode group 2. The bent portion 301 passes through the mounting groove 601 and is connected to the connecting piece 6. The paired bent portions 301 are disposed back to back.

[0044] For the battery cell provided by the embodiment of the present utility model, the electrode post 5 and the electrode tab 3 are connected by the connecting piece 6. The electrode post 5 and the electrode tab 3 are respectively located at opposite ends of the connecting piece 6. The connecting piece 6 is disposed on the multiple electrode groups 2 and is located inside the cover plate 4, without bending the connecting piece 6. The paired electrode tabs 3 are disposed back to back and pass through one mounting groove 601, reducing the total number of bends of the connecting piece 6 and the electrode group 2. The electrode post 5 and the electrode group 2 are not in the same vertical plane, reducing the installation thickness of the battery cell, thereby improving the space utilization rate of the battery cell. Moreover, the processing procedures of the connecting piece 6 and the electrode group 2 are also reduced, improving the production efficiency. Since both the electrode post 5 and the connecting piece 6 are disposed on the cover plate 4, the electrode post 5 and the connecting piece 6 can be installed on the housing 1 together with the cover plate 4, which is also convenient for installation and disassembly.

[0045] Specifically, the interior of the housing 1 has a cavity, and multiple pairs of electrode groups 2 are stacked and disposed in the cavity. One side of the housing 1 is provided with an opening, and multiple pairs of electrode groups 2 are provided with multiple pairs of electrode tabs 3 on the side close to the opening. Each electrode group 2 is correspondingly provided with a positive electrode tab and a negative electrode tab, and multiple positive electrode tabs and multiple negative electrode tabs are respectively paired. The through hole 401 of the cover plate 4 is used to leave a connection space for the connecting piece 6 and the electrode tab 3. Since the electrode post 5 is disposed on the cover plate 4, the electrode tab 3 and the electrode post 5 are misaligned, thereby reducing the installation thickness.

[0046] A pair of electrode posts 5 includes a positive electrode post and a negative electrode post. Correspondingly, the electrode tab 3 includes a positive electrode tab and a negative electrode tab. One of the connecting pieces 6 connects the positive electrode post and the positive electrode tabs of the multiple electrode groups 2, and the other connecting piece 6 connects the negative electrode post and the negative electrode tabs of the multiple electrode groups 2. The connecting piece 6 needs to be conductive to achieve electrical conduction between the electrode tab 3 and the electrode post 5. A gap is left between the two connecting pieces 6 to prevent short circuit between the positive electrode post and the negative electrode post.

[0047] It should be noted that the embodiment of the present utility model does not limit the number of the electrode groups 2, which can be selected according to needs. For example, one pair, two pairs or more than two pairs can be selected. Exemplarily, as Figure 8As shown, two pairs of electrode groups 2 are provided. The two positive electrode tabs of each pair of electrode groups 2 form a pair and are bent backward. Similarly, the two negative electrode tabs of each pair of electrode groups 2 form a pair and are bent backward.

[0048] In addition, the embodiments of the present utility model do not limit the connection between the connecting piece 6 and the electrode post 5 and the electrode tab 3 either, and any existing connection form can be selected according to needs. In order to improve the connection stability between the connecting piece 6 and the electrode post 5 and the electrode tab 3, in one embodiment, solder pads are respectively arranged at opposite ends of the connecting piece 6 and are welded to the electrode post 5 and the electrode tab 3.

[0049] In one embodiment, as Figure 5 shown, the bending portion 301 includes a first connection segment 3011 and a second connection segment 3012 perpendicularly connected to the first connection segment 3011. A transition fillet is provided between the first connection segment 3011 and the second connection segment 3012. The first connection segment 3011 is connected to the electrode group 2 and there is a gap between the first connection segment 3011 and the installation groove 601 of the connecting piece 6. The bottom surface of the second connection segment 3012 is disposed along the width direction of the cover plate 4 on the top surface of the connecting piece 6. The top and bottom directions of the embodiments of the present utility model are as Figure 1 shown.

[0050] The first connection segment 3011 is used to connect the electrode group 2. There is a gap between the first connection segment 3011 and the connecting piece 6, which can prevent the connecting piece 6 from tearing the electrode tab 3. The electrode tabs 3 are arranged in pairs, and the bottom surface of the second connection segment 3012 is disposed along the width direction of the cover plate 4 on the top surface of the connecting piece 6, which can save the installation space in the width direction of the cover plate 4, thereby reducing the width of the through hole 401 to ensure the structural strength of the cover plate 4.

[0051] As Figure 8 and Figure 9 shown, the second connection segment 3012 passes through the installation groove 601 of the connecting piece 6 before bending and is welded to the surface of the connecting piece 6 as a whole after bending.

[0052] In one embodiment, as Figure 5 shown, the height H of the second connection segment 3012 relative to the electrode group 2 is 1.5 mm to 5 mm. It can save the space of the battery cell in the height direction of the electrode group 2 to the greatest extent and improve the space utilization rate of the battery cell while ensuring the strength and reliability of the second connection segment 3012.

[0053] Furthermore, in one embodiment, as Figure 5As shown, the connection point between the first connection segment 3011 and the electrode group 2 is biased towards one side of the electrode group 2, and the offset W ≤ 1 / 2T1, where T1 is the thickness of the electrode group 2, and T1 ranges from 6 mm to 30 mm. The thickness of the electrode group 2 can be selected and set according to the capacity of the battery cell. By setting the offset, the flatness of the end face of the second connection segment 3012 after folding can be ensured, so as to omit the die-cutting process of the tab 3, reduce the use cost and improve the production efficiency. The end face of the second connection segment 3012 is as Figure 5 shown by S in

[0054] In one embodiment, as Figure 5 shown, one end of the electrode group 2 connected to the first connection segment 3011 forms a folding inclined surface, and the height h of the folding inclined surface is 0.2 mm to 3.5 mm. The height of the folding inclined surface is determined by the thickness of the electrode group 2. Setting the folding inclined surface can compact the tab 3 after folding, so that the electrode group 2 has a certain load-bearing capacity.

[0055] In one embodiment, as Figure 5 shown, the thickness T2 of the second connection segment 3012 is 0.1 mm to 2.5 mm. By limiting the thickness of the second connection segment 3012, the space in the height direction of the electrode group 2 can be further saved, and the space utilization rate of the battery cell can be improved.

[0056] In one embodiment, as Figure 5 shown, the radius R of the transition fillet between the first connection segment 3011 and the second connection segment 3012 is 0.1 mm to 0.3 mm. By setting a transition fillet between the first connection segment 3011 and the second connection segment 3012, the structural strength of the tab 3 can be ensured, and the tab 3 can be prevented from being torn.

[0057] In one embodiment, as Figure 5 shown, the gap length D between the first connection segment 3011 and the mounting groove 601 of the connecting piece 6 is D ≥ 0.2 mm. By limiting the size of the gap length between the first connection segment 3011 and the connecting piece 6, space can be reserved to prevent the connecting piece 6 from tearing the tab 3. Through the above size limitation of the tab 3, the reliability and consistency of multiple tabs 3 after bending can also be ensured.

[0058] In one embodiment, as Figure 6 and Figure 7 shown, the through hole 401 is a rectangular through hole, the length direction of the rectangular through hole is the same as the length direction of the cover plate 4, and a pair of pole columns 5 are located on opposite sides in the length direction of the rectangular through hole. The through hole 401 being a rectangular through hole can be adapted to the tab 3 and the connecting piece 6. A pair of pole columns 5 being located on opposite sides in the length direction of the rectangular through hole can make the pole columns 5, the connecting piece 6 and the tab 3 arranged in a staggered manner, avoiding the superposition of their thicknesses and improving the space utilization rate of the battery cell. The length direction of the cover plate 4 is as Figure 2 shown by the arrow L in

[0059] In one embodiment, as Figure 3 shown, an insulating washer 7 and a sealing ring 8 are further provided between the terminal post 5 and the cover plate 4. The insulating washer 7 is disposed above the sealing ring 8. The insulating washer 7 can simultaneously achieve the effects of insulation and sealing. The setting of the sealing ring 8 can further ensure the sealing performance of the terminal post 5. The sealing ring 8 can adopt conventional sealing rings such as rubber sealing rings and silicone rubber sealing rings. An insulating plate 9 is further provided between the connecting piece 6 and the housing 1 to prevent short - circuit connection between the positive terminal post and the negative terminal post.

[0060] It should be noted that the embodiment of the present utility model does not limit the material of the cover plate 4 either. For example, the cover plate 4 can be selected as a light aluminum plate. In addition, the materials of the insulating washer 7 and the insulating plate 9 are not limited either. For example, both the insulating washer 7 and the insulating plate 9 can adopt plastic parts.

[0061] In one embodiment, as Figure 1 and Figure 2 shown, a sealing plate 10 for sealing the through - hole 401 is further provided on the cover plate 4, and a liquid injection hole 11 is provided on the sealing plate 10. The terminal post 5, the insulating washer 7, the sealing ring 8, the sealing plate 10 and the insulating plate 9 are all arranged on the cover plate 4, and can be installed and disassembled as a whole, which is beneficial to improving the production efficiency of the battery cell.

[0062] According to an embodiment of the present utility model, on the other hand, a battery pack is further provided, including: a plurality of battery cells.

[0063] Because the battery pack includes battery cells and has the same effects as the battery cells, that is, the terminal post 5 and the tab 3 are connected by the connecting piece 6. The terminal post 5 and the tab 3 are respectively located at opposite ends of the connecting piece 6. The connecting piece 6 is disposed on a plurality of pole groups 2 and is located inside the cover plate 4, and there is no need to bend the connecting piece 6. The paired tabs 3 are arranged back - to - back and pass through an installation groove 601, reducing the total number of bending times of the connecting piece 6 and the pole group 2. The terminal post 5 and the pole group 2 are not in the same vertical plane, reducing the installation thickness of the battery cell, thereby improving the space utilization rate of the battery cell. Moreover, the processing procedures of the connecting piece 6 and the pole group 2 are also reduced, improving the production efficiency. Since both the terminal post 5 and the connecting piece 6 are disposed on the cover plate 4, the terminal post 5 and the connecting piece 6 can be installed on the housing 1 together with the cover plate 4, which is also convenient for installation and disassembly.

[0064] Specifically, a plurality of battery cells can be selected to be connected in series to form a battery pack, or can be selected to be connected in parallel to form a battery pack, or can be combined in series - parallel to form a battery pack. In this regard, the embodiment of the present utility model does not have many restrictions.

[0065] To implement the basic functions of the battery pack, the battery pack in this embodiment may further include other necessary modules or components, such as a battery management system, a heat dissipation system, etc. It should be noted that for the other necessary modules or components included in the battery pack, any suitable existing structure can be selected. To clearly and briefly illustrate the technical solution provided in this embodiment, the above parts will not be elaborated herein, and the accompanying drawings of the specification have also been correspondingly simplified. However, it should be understood that the scope of the present utility model is not limited thereby.

[0066] Although the embodiments of the present utility model 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 utility model, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that: include: A shell having an opening, a plurality of pairs of pole groups arranged in the opening, and a plurality of pairs of pole ears corresponding to the pole groups one by one; A cover plate, covering the opening, wherein a through hole and a pair of poles are provided on the cover plate, wherein the through hole is located between the pair of poles; A pair of connecting pieces, provided on the plurality of pole groups and located on the inner side of the cover plate, one end of the pair of connecting pieces being respectively connected to a pair of poles, and the other ends thereof extending to the through holes and respectively provided with a plurality of mounting grooves; The pole lug comprises a bent portion formed by gathering the ends of the pole group, the bent portion passes through the mounting groove and is connected to the connecting piece, and the bent portions arranged in pairs are arranged back to back.

2. The battery cell according to claim 1, characterized in that: The bending portion includes a first connecting section and a second connecting section perpendicularly connected to the first connecting section, a transition fillet is provided between the first connecting section and the second connecting section, the first connecting section is connected to the pole group and a gap is left between the first connecting section and the mounting groove of the connecting plate, and the bottom surface of the second connecting section is attached to the top surface of the connecting plate along the width direction of the cover plate.

3. The battery cell according to claim 2, characterized in that: A height H of the second connecting section relative to the pole group is 1.5 mm to 5 mm.

4. The battery cell according to claim 2, characterized in that: The connection between the first connecting section and the pole group is biased toward one side of the pole group, and the offset W is ≤ 1 / 2T1, wherein T1 is the thickness of the pole group, and T1 is 6 mm to 30 mm.

5. The battery cell according to claim 4, characterized in that: One end of the pole group connected to the first connecting section forms a gathered slope, and the height h of the gathered slope is 0.2 mm to 3.5 mm.

6. The battery cell according to claim 2, characterized in that: The thickness T2 of the second connecting section is 0.1 mm to 2.5 mm.

7. The battery cell according to claim 2, characterized in that: The radius R of the transition fillet between the first connecting segment and the second connecting segment is 0.1 mm to 0.3 mm.

8. The battery cell according to claim 2, characterized in that: A gap length D between the first connecting section and the mounting groove of the connecting piece is ≥0.2 mm.

9. The battery cell according to any one of claims 1 to 8, characterized in that: The through hole is a rectangular through hole, the length direction of the rectangular through hole is consistent with the length direction of the cover plate, and a pair of poles are located at opposite sides of the length direction of the rectangular through hole.

10. A battery pack, characterized in that: include: A plurality of battery cells according to any one of claims 1 to 9.

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