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 pair of pole columns and a pair of connecting sheets, a plurality of pairs of pole groups and a plurality of pairs of tabs in one-to-one correspondence with the pole groups are arranged in the shell, and through holes and mounting holes positioned in two opposite sides of the through holes are formed in one side, opposite to the tabs, of the shell; the pair of poles are respectively mounted in the mounting holes and extend to the outer side of the shell; the pair of connecting pieces are arranged on the pole groups and located on the inner side of the shell, 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 mounting thickness of the battery cell is reduced, 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] Currently, the battery cells of battery packs generally use connecting pieces to connect the pole columns and 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 is required, resulting in a 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 a low space utilization rate of the battery cell.

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

[0006] A housing, which is internally provided with multiple pairs of pole groups and multiple pairs of pole ears corresponding to the pole groups one by one. A through hole and mounting holes located on opposite sides of the through hole are formed on one side of the housing opposite to the pole ears;

[0007] A pair of pole columns, which are respectively installed in the mounting holes and extend to the outside of the housing;

[0008] A pair of connecting pieces, which are arranged on multiple pole groups and located inside the housing. 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 multiple mounting slots;

[0009] The pole ear includes a bent portion formed by converging the end of the pole group. The bent portion passes through the mounting slot and is connected to the connecting piece. 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 connecting pieces are both integrally arranged on the housing, and the structural strength is relatively high. The pole columns and the pole ears are connected through the connecting pieces. The pole columns and the pole ears are respectively located at opposite ends of the connecting piece. The connecting piece is directly arranged on multiple pole groups and installed inside the housing, and there is no need to bend the connecting piece. The paired pole ears are arranged back to back and pass through one mounting slot, reducing the total bending times 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.

[0011] In an alternative embodiment, the terminal post includes a column body and a boss provided at one end of the column body. The column body is disposed in the mounting hole, and a sealing ring is provided between the column body and the mounting hole. An insulating washer is provided between the bottom surface of the boss and the top surface of the housing. An insulating plate is also provided between the connecting piece and the housing.

[0012] Advantageous effects: By providing an insulating washer between the bottom surface of the boss and the top surface of the housing, the insulation and sealing performance of the terminal post can be improved. The boss facilitates the fixation of the insulating washer, and by providing a sealing ring between the column body and the mounting hole, the sealing effect can be further enhanced. An insulating plate is provided between the connecting piece and the housing to avoid short circuits and improve safety.

[0013] In an alternative embodiment, a sealing plate for sealing the through hole is further provided on the housing, and a liquid injection hole is provided on the sealing plate.

[0014] Advantageous effects: The sealing plate is used to seal the through hole, and the liquid injection hole is used to inject electrolyte.

[0015] 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. The first connecting section is connected to the electrode group and there is a gap between the first connecting section and the connecting piece. The bottom surface of the second connecting section is disposed along the width direction of the housing on the top surface of the connecting piece.

[0016] Advantageous effects: The first connecting section is used to connect the electrode group. A gap is provided between the first connecting section and the connecting piece, which can prevent the connecting piece from tearing the tab. The tabs are arranged in pairs, and the bottom surface of the second connecting section is disposed along the width direction of the housing on the top surface of the connecting piece, which can save the installation space in the width direction of the housing, thereby reducing the width of the through hole to ensure the structural strength of the housing.

[0017] In an alternative embodiment, the height H of the second connecting section relative to the electrode group is 1.5 mm to 5 mm;

[0018] and / or, the thickness T1 of the second connecting section is 0.1 mm to 2.5 mm.

[0019] Advantageous effects: By setting the height of the second connecting section relative to the electrode group, the space in the height direction of the battery cell 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. By limiting the thickness of the second connecting section, the space in the height direction of the battery cell can be further saved, improving the space utilization rate of the battery cell.

[0020] In an alternative embodiment, the connection point between the first connection segment and the electrode group is biased towards one side of the electrode group, and the offset W ≤ 1 / 2T2, where T2 is the thickness of the electrode group, and T2 ranges from 6 mm to 30 mm.

[0021] Advantageous effects: By setting the offset and defining the offset size, the flatness of the end face of the second connection segment after folding can be ensured, so as to omit the ear tab die-cutting process, reduce the use cost and improve the production efficiency.

[0022] In an alternative embodiment, one end of the electrode group connected to the first connection segment forms a folding slope, and the height h of the folding slope is from 0.2 mm to 3.5 mm.

[0023] Advantageous effects: The height of the folding slope is determined by the thickness of the electrode group. Setting the folding slope can compact the ear tab after folding, so that the electrode group has a certain load-bearing capacity.

[0024] In an alternative embodiment, the radius R of the transition fillet between the first connection segment and the second connection segment is from 0.1 mm to 0.3 mm.

[0025] Advantageous effects: By setting the transition fillet, the structural strength of the ear tab can be ensured, and the ear tab can be prevented from being torn.

[0026] In an alternative embodiment, the gap length D between the first connection segment and the connection piece is D ≥ 0.2 mm.

[0027] Advantageous effects: By defining the size of the gap length between the first connection segment and the connection piece, space can be reserved to prevent the connection piece from tearing the ear tab.

[0028] In a second aspect, the present invention further provides a battery pack, including: a plurality of the above-mentioned battery cells.

[0029] Advantageous effects: Since the battery pack includes battery cells, it has the same effects as the battery cells, that is, the pole column and the connection piece are both integrally arranged on the housing, and the structural strength is relatively high. The pole column and the ear tab are connected by the connection piece, and the pole column and the ear tab are respectively located at opposite ends of the connection piece. The connection piece is directly arranged on a plurality of electrode groups and installed inside the housing without bending the connection piece. The paired ear tabs are arranged back to back and pass through an installation slot, reducing the total number of bends of the connection piece and the electrode group. The pole column and the electrode 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 connection piece and the electrode group are also reduced, improving the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] 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 drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0031] Figure 1 Structural schematic diagram of a battery cell according to an embodiment of the present utility model;

[0032] Figure 2 For Figure 1 Top view;

[0033] Figure 3 For Figure 2 Partial structural schematic diagram of the A-A cross-section in

[0034] Figure 4 For Figure 2 B-B cross-sectional view in

[0035] Figure 5 For Figure 4 Enlarged view at C in

[0036] Figure 6 Partial structural schematic diagram of a battery cell before the ear of the battery cell is bent according to an embodiment of the present utility model;

[0037] Figure 7 Partial structural schematic diagram of a battery cell according to an embodiment of the present utility model;

[0038] Figure 8 Structural schematic diagram of the ear of the battery cell before bending and the connecting piece according to an embodiment of the present utility model;

[0039] Figure 9 Structural schematic diagram of the ear of the battery cell after bending and the connecting piece according to an embodiment of the present utility model.

[0040] Explanation of reference numerals:

[0041] 1. Housing; 101. Through hole; 2. Electrode group; 3. Ear; 301. Bent portion; 3011. First connection section; 3012. Second connection section; 4. Electrode post; 401. Column body; 402. Boss; 5. Connecting piece; 501. Installation groove; 6. Sealing ring; 7. Insulating washer; 8. Insulating plate; 9. Sealing plate; 10. Liquid injection hole. Detailed embodiments

[0042] 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 of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0043] The following will describe the embodiments of the present utility model in conjunction with Figures 1 to 9 , to describe the embodiments of the present utility model.

[0044] According to the embodiments of the present utility model, on the one hand, as Figures 1 to 3 shown, a battery cell is provided, mainly including: a housing 1, a pair of pole columns 4, and a pair of connection plates 5. Inside the housing 1, multiple pairs of pole groups 2 and multiple pairs of pole tabs 3 corresponding to the pole groups 2 one by one are provided. A through hole 101 and mounting holes located on opposite sides of the through hole 101 are formed on one side of the housing 1 opposite to the pole tabs 3. A pair of pole columns 4 are respectively installed in the mounting holes and extend to the outside of the housing 1. A pair of connection plates 5 are arranged on the multiple pole groups 2 and located inside the housing 1. One ends of the pair of connection plates 5 are respectively connected to the pair of pole columns 4, and the opposite ends both extend to the through hole 101 and are respectively provided with multiple mounting slots 501. The pole tab 3 includes a bent portion 301 formed by converging the end of the pole group 2. The bent portion 301 passes through the mounting slot 501 and is connected to the connection plate 5. The paired bent portions 301 are arranged back to back.

[0045] For the battery cell provided by the present utility model, both the pole column 4 and the connection plate 5 are integrally arranged on the housing 1, and the structural strength is relatively high. By connecting the pole column 4 and the pole tab 3 through the connection plate 5, the pole column 4 and the pole tab 3 are respectively located at opposite ends of the connection plate 5. The connection plate 5 is directly arranged on the multiple pole groups 2 and installed inside the housing 1 without bending the connection plate 5. The paired pole tabs 3 are arranged back to back and pass through one mounting slot 501, reducing the total number of bends of the connection plate 5 and the pole group 2. The pole column 4 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 connection plate 5 and the pole group 2 are also reduced, improving the production efficiency.

[0046] Specifically, side plates are provided around the housing 1, a bottom plate is provided at the bottom, and a top plate is provided at the top. The four side plates, the top plate, and the bottom plate are integrally formed and enclose a cavity. Multiple pairs of pole groups 2 are stacked and arranged in the cavity. On one side of the multiple pairs of pole groups 2 close to the top plate, multiple pairs of pole lugs 3 are provided. Each pole group 2 is correspondingly provided with a positive pole lug and a negative pole lug, and multiple positive pole lugs and multiple negative pole lugs are respectively arranged in pairs. Through holes 101 and a pair of pole posts 4 are provided on the top plate at intervals, and the through holes 101 are provided between the pair of pole posts 4. The through holes 101 are used to leave a connection space for the connection piece 5 and the pole lug 3. The pole lug 3 and the pole post 4 are arranged in a staggered manner, and the length direction of the connection piece 5 is the same as the length direction of the housing 1, which can reduce the installation thickness of the housing 1.

[0047] A pair of pole posts 4 includes a positive pole post and a negative pole post. Correspondingly, the pole lug 3 includes a positive pole lug and a negative pole lug. As Figure 8 and Figure 9 shown, a pair of connection pieces 5 are arranged on the top of the multiple pairs of pole groups 2 in a back-to-back manner. One of the connection pieces 5 connects the positive pole post and the positive pole lugs of the multiple pole groups 2, and the other connection piece 5 connects the negative pole post and the negative pole lugs of the multiple pole groups 2. The connection piece 5 needs to be conductive to achieve electrical conduction between the pole lug 3 and the pole post 4. A gap is left between the two connection pieces 5 to prevent short circuit between the positive pole post and the negative pole post.

[0048] It should be noted that the top and bottom directions of the embodiments of the present invention are as Figure 1 shown.

[0049] It should be noted that the embodiments of the present invention do not limit the number of pole 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 8 and Figure 9 shown, two pairs of pole groups 2 are provided. The two positive pole lugs of each pair of pole groups 2 form a pair and are bent back-to-back. Similarly, the two negative pole lugs of each pair of pole groups 2 form a pair and are bent back-to-back.

[0050] In addition, the embodiments of the present invention do not limit the connection of the connection piece 5 with the pole post 4 and the pole lug 3, and any existing connection form can be selected according to needs. In order to improve the connection stability between the connection piece 5 and the pole post 4 and the pole lug 3, in one embodiment, welding pads are respectively provided at opposite ends of the connection piece 5 and are welded to the pole post 4 and the pole lug 3.

[0051] In one embodiment, as Figure 3As shown, the terminal post 4 includes a post body 401 and a boss 402 provided at one end of the post body 401. The post body 401 is provided in the mounting hole, and a sealing ring 6 is provided between the post body 401 and the mounting hole. An insulating washer 7 is provided between the bottom surface of the boss 402 and the top surface of the housing 1. An insulating plate 8 is also provided between the connecting piece 5 and the housing 1. The sealing ring 6 can be a conventional sealing ring such as a rubber sealing ring or a silicone rubber sealing ring. The insulating washer 7 and the insulating plate 8 can be made of plastic parts.

[0052] By providing the insulating washer 7 between the bottom surface of the boss 402 and the top surface of the housing 1, the insulation and sealing performance of the terminal post 4 can be improved. The boss 402 facilitates the fixing of the insulating washer 7, and by providing the sealing ring 6 between the post body 401 and the mounting hole, the sealing effect can be further improved. By providing the insulating plate 8 between the connecting piece 5 and the housing 1, short circuits can be avoided and safety can be improved.

[0053] In one embodiment, as Figure 1 and Figure 2 shown, the housing 1 is further provided with a sealing plate 9 for sealing the through hole 101, and the sealing plate 9 is provided with a liquid injection hole 10. The sealing plate 9 is used to seal the through hole 101, and the liquid injection hole 10 is used to inject electrolyte. The terminal post 4, the insulating washer 7, the sealing ring 6, the sealing plate 9 and the insulating plate 8 are all provided on the housing 1, having good structural strength.

[0054] In one embodiment, as Figure 5 shown, the bent portion 301 includes a first connecting section 3011 and a second connecting section 3012 perpendicularly connected to the first connecting section 3011. A transition fillet is provided between the first connecting section 3011 and the second connecting section 3012. The first connecting section 3011 is connected to the electrode group 2 and there is a gap between the first connecting section 3011 and the connecting piece 5. The bottom surface of the second connecting section 3012 is attached to the top surface of the connecting piece 5 along the width direction of the housing 1.

[0055] The first connecting section 3011 is used to connect the electrode group 2. There is a gap between the first connecting section 3011 and the connecting piece 5, which can prevent the connecting piece 5 from tearing the tab 3. The tabs 3 are arranged in pairs, and the bottom surface of the second connecting section 3012 is attached to the top surface of the connecting piece 5 along the width direction of the housing 1, which can save the installation space in the width direction of the housing 1, thereby reducing the width of the through hole 101 to ensure the structural strength of the housing 1.

[0056] As Figures 6 to 9 shown, the second connecting section 3012 passes through the mounting groove 601 of the connecting piece 5 before bending, and is welded to the surface of the connecting piece 5 as a whole after bending.

[0057] In one embodiment, as Figure 5As shown, the height H of the second connection section 3012 relative to the pole group 2 is 1.5 mm to 5 mm. By setting the height of the second connection section 3012 relative to the pole group 2, it is possible to save the space in the height direction of the battery cell to the greatest extent while ensuring the strength and reliability of the second connection section 3012, and improve the space utilization rate of the battery cell.

[0058] In one embodiment, as Figure 5 shown, the thickness T1 of the second connection section 3012 is 0.1 mm to 2.5 mm. By limiting the thickness of the second connection section 3012, it is possible to further save the space in the height direction of the battery cell and improve the space utilization rate of the battery cell.

[0059] In one embodiment, as Figure 5 shown, the connection part of the first connection section 3011 and the pole group 2 is biased towards one side of the pole group 2, and the offset W ≤ 1 / 2T2, where T2 is the thickness of the pole group 2, and T2 is 6 mm to 30 mm. By setting the offset and limiting the offset size, it is possible to ensure the flatness of the end face of the second connection section 3012 after folding, 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 section 3012 is as Figure 5 shown as S in

[0060] In one embodiment, as Figure 5 shown, one end of the pole group 2 connected to the first connection section 3011 forms a folding inclined plane, and the height h of the folding inclined plane is 0.2 mm to 3.5 mm. The height of the folding inclined plane is determined by the thickness of the pole group 2. Setting the folding inclined plane can compact the tab 3 after folding, so that the pole group 2 has a certain load-bearing capacity.

[0061] In one embodiment, as Figure 5 shown, the radius R of the transition fillet between the first connection section 3011 and the second connection section 3012 is 0.1 mm to 0.3 mm. By setting the transition fillet, it is possible to ensure the structural strength of the tab 3 and avoid tearing of the tab 3.

[0062] In one embodiment, as Figure 5 shown, the gap length D between the first connection section 3011 and the connection piece 5 is D ≥ 0.2 mm. By limiting the size of the gap length between the first connection section 3011 and the connection piece 5, it is possible to reserve space and avoid the connection piece 5 tearing the tab 3. Through the above-mentioned size limitation of the tab 3, it is also possible to ensure the reliability and consistency of multiple tabs 3 after bending.

[0063] According to an embodiment of the present invention, on the other hand, a battery pack is further provided, including: a plurality of the above-mentioned battery cells.

[0064] Since the battery pack includes battery cells and has the same effect as the battery cells, that is, the pole column 4 and the connecting piece 5 are both integrally arranged on the housing 1, and the structural strength is relatively high. The pole column 4 and the pole ear 3 are connected by the connecting piece 5. The pole column 4 and the pole ear 3 are respectively located at opposite ends of the connecting piece 5. The connecting piece 5 is directly arranged on a plurality of pole groups 2 and installed inside the housing 1 without bending the connecting piece 5. The paired pole ears 3 are arranged back to back and pass through an installation groove 501, reducing the total number of bends of the connecting piece 5 and the pole groups 2. The pole column 4 and the pole groups 2 are not in the same vertical plane, reducing the installation thickness of the battery cells, thereby improving the space utilization rate of the battery cells. Moreover, the processing procedures of the connecting piece 5 and the pole groups 2 are also reduced, improving the production efficiency.

[0065] Specifically, multiple 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 and parallel to form a battery pack. In this regard, the embodiments of the present invention do not have many restrictions.

[0066] To achieve 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 the other necessary modules or components included in the battery pack can be any suitable existing structures. To clearly and briefly illustrate the technical solutions provided in this embodiment, the above parts will not be described in detail here, and the accompanying drawings of the specification have also been simplified accordingly. However, it should be understood that the scope of the present invention is not limited thereby.

[0067] Although the 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 battery cell, characterized in that: include: A shell, wherein a plurality of pairs of pole groups and a plurality of pairs of pole ears corresponding to the pole groups are arranged inside, and a through hole and mounting holes located on opposite sides of the through hole are opened on a side of the shell opposite to the pole ears; A pair of poles, respectively installed in the installation holes and extending to the outside of the shell; A pair of connecting pieces, provided on the plurality of pole groups and located on the inner side of the housing, one end of the pair of connecting pieces being respectively connected to a pair of poles, and the other ends of the pair of connecting pieces 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 pole includes a column and a boss arranged at one end of the column. The column is arranged in the mounting hole and a sealing ring is arranged between the column and the mounting hole. An insulating gasket is arranged between the bottom surface of the boss and the top surface of the shell. An insulating plate is also arranged between the connecting piece and the shell.

3. The battery cell according to claim 1, characterized in that: The shell is also provided with a sealing plate for sealing the through hole, and the sealing plate is provided with a liquid injection hole.

4. The battery cell according to any one of claims 1 to 3, 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 connecting sheet, and the bottom surface of the second connecting section is attached to the top surface of the connecting sheet along the width direction of the shell.

5. The battery cell according to claim 4, characterized in that: The height H of the second connecting section relative to the pole group is 1.5 mm to 5 mm; And / or, the thickness T1 of the second connecting segment is 0.1 mm to 2.5 mm.

6. The battery cell according to claim 4, 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 / 2T2, wherein T2 is the thickness of the pole group, and T2 is 6 mm to 30 mm.

7. 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.

8. The battery cell according to claim 4, 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.

9. The battery cell according to claim 4, characterized in that: The gap length D between the first connecting section and the connecting sheet is ≥0.2 mm.

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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