Battery cell and battery pack

Abstract

The utility model relates to the technical field of battery cells, and discloses a battery cell and a battery pack. Wherein the battery cell comprises: two ends of a shell are provided with openings and cover plates for sealing the openings, the cover plates are provided with pole columns, and at least one cover plate is provided with a through hole; the pole group is arranged in the shell, the two ends of the pole group are provided with pole lugs, the pole lugs and the corresponding pole columns are arranged in a staggered mode, at least one pole lug comprises a body connected with the pole group and a bent part bent towards one side from the end of the body, and the bent part corresponds to the through hole; the pair of connecting sheets are arranged in the shell and are respectively arranged at the two ends of the pole group, the connecting sheets are used for connecting the pole columns and the corresponding tabs, and at least one connecting sheet is fixed in a space defined by the body and the bending part and is attached to the lower surface of the bending part. The tabs and the poles are arranged in a staggered manner, so that the installation thickness of the poles and the tabs in a connection state is reduced, and the utilization rate of the internal space of the shell is improved; and secondly, the tabs are connected with the connecting sheets through the bending parts, so that the operation difficulty in the connecting process can be reduced.

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] The connecting piece in the battery cell is a metal piece used to connect the pole column of the battery cell and the pole ear of the pole group. It ensures the smooth flow of current between the pole column and the pole ear, and realizes the storage and release of electric energy of the battery cell.

[0003] However, the method of connecting the connecting piece and the pole ear adopted in the related art is not only relatively complicated to operate, but also occupies more internal space 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 problems that the connection method between the connecting piece and the pole ear in the related art is complicated and occupies more internal space of the battery cell.

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

[0006] A housing with openings at both ends and a cover plate for sealing the openings. The cover plate is provided with a pole column, and at least one of the cover plates is provided with a through hole;

[0007] A pole group disposed in the housing and having pole ears at both ends. The pole ears are arranged in a staggered manner with the corresponding pole columns. At least one of the pole ears includes a body connected to the pole group and a bent portion bent from the end of the body towards one side. The bent portion is arranged corresponding to the through hole;

[0008] A pair of connecting pieces disposed in the housing and respectively arranged at both ends of the pole group. The connecting pieces are used to connect the pole column and its corresponding pole ear. At least one of the connecting pieces is fixed in the space defined by the body and the bent portion and is attached to the lower surface of the bent portion.

[0009] Beneficial effects: By providing an opening on the housing that communicates with its interior, the present utility model facilitates the assembly of components such as the electrode group into the housing by the operator, improving the convenience of assembly. Further, a cover plate is used to seal the opening, ensuring the sealing of the battery cell, reducing the possibility of external moisture, dust and other impurities entering the interior of the battery cell, guaranteeing the cleanliness and stability of the interior environment of the battery cell, and thus being conducive to extending the service life of the battery cell. Secondly, the pole posts and the pole ears of the present utility model are arranged in a staggered manner, making use of the space in other directions inside the housing. Compared with the existing connection piece and pole ear both arranged along the axial direction of the pole post, the internal space of the housing occupied by the connection piece and the pole ear in the height direction (axial direction of the pole post) of the housing in the connected state is reduced, improving the utilization rate of the internal space of the housing, and thus enabling the battery cell to store more energy under the same volume. Moreover, the pole ear is connected to the connection piece through a bent portion, which can reduce the operation difficulty of connecting the pole ear and the connection piece and also reduce the occupation of the internal space of the housing in the connected state of the two.

[0010] In an alternative embodiment, the connection piece includes a pole post connection portion connected to the pole post and a pole ear connection portion connected to the pole ear.

[0011] Beneficial effects: Since the pole ears and the pole posts in the present utility model are arranged in a staggered manner, the connection piece is divided into a pole post connection portion and a pole ear connection portion, which can adapt the position of the connection piece to the pole ears and the pole posts, so as to connect the pole ears and the pole posts and realize the smooth flow of current between the pole ears and the pole posts.

[0012] In an alternative embodiment, the height of the body is consistent with the thickness of the pole ear connection portion.

[0013] Beneficial effects: The present utility model makes the height of the body in the pole ear match the thickness of the pole ear connection portion. On the one hand, it can make the lower surface of the bent portion closely fit on the connection piece. In this way, not only can the connection stability between the two be enhanced, but also the contact resistance can be reduced and the transmission efficiency of current between the pole ear and the pole post can be improved. On the other hand, it can make the structure of the connection piece and the pole ear more compact in the connected state, reducing the unnecessary occupation of the internal space of the housing.

[0014] In an alternative embodiment, a gap is left between the pole ear connection portion and the inner wall of the housing extending along its length direction, and the bent portion is arranged on the upper surface of the pole ear connection portion through the body passing through the gap and the through hole.

[0015] Beneficial effects: Since the lower surface of the bent portion needs to fit against the upper surface of the tab connection portion, generally, in order to make the bent portion reach the upper surface of the tab connection portion, a channel opening suitable for the body to pass through needs to be provided on the tab connection portion. However, this will make the structure of the tab connection portion relatively complex and increase the upfront manufacturing cost. Therefore, to solve the above problems, in the present utility model, the body passes through the gap between the tab connection portion and the inner wall of the housing extending in the length direction and the through hole on the cover plate, and no complex adjustment needs to be made to the structure of the connection piece, simplifying the structure of the connection piece itself.

[0016] In an alternative embodiment, the body is perpendicularly arranged with respect to the bent portion.

[0017] Beneficial effects: In the present utility model, the body of the tab is perpendicularly arranged with respect to the bent portion of the tab, which can make the structure of the tab in the housing more compact, optimize the internal space of the housing, and improve the energy density of the battery cell.

[0018] In an alternative embodiment, the tab is arranged offset with respect to the corresponding terminal along the length direction of the housing.

[0019] Beneficial effects: In the present utility model, the terminal and the tab are arranged offset along the length direction of the housing, which can utilize the space in the length direction inside the housing and arrange the connection piece on the electrode group along the length direction of the housing. In this way, compared with the existing connection piece and tab both arranged along the axial direction of the terminal, the longitudinal distance between the tab and the terminal will become relatively smaller, thereby reducing the occupation of the internal space of the housing.

[0020] In an alternative embodiment, the connection piece is welded to the bent portion.

[0021] Beneficial effects: In the present utility model, the connection piece is connected to the bent portion by welding, which can increase the connection area between the tab and the connection piece, reduce the resistance at the connection between the two, optimize the current conduction path, and improve the performance of the battery cell during charging and discharging.

[0022] In an alternative embodiment, the cover plate is provided with an upper liquid injection hole and an explosion-proof valve.

[0023] Beneficial effects: In the present utility model, the liquid injection hole and the explosion-proof valve are arranged on the cover plate. On the one hand, it can make the structure of the cover plate itself more compact and optimize the structural layout on the cover plate; on the other hand, it is convenient to add electrolyte into the battery cell, and at the same time, it can prevent the pressure inside the battery cell from being too high, improving the safety of the battery cell during use.

[0024] In an alternative embodiment, a sealing plate is provided on the cover plate, and the sealing plate is welded to the through hole to seal the through hole.

[0025] Beneficial effects: In the present utility model, the sealing plate and the through hole are welded and connected. On the one hand, the connection strength between the two can be improved, reducing the possibility of the sealing plate falling off during the use of the battery cell. On the other hand, the occurrence of gaps between the sealing plate and the hole wall of the through hole can be avoided, improving the self-sealing performance of the housing and reducing the possibility of external impurities entering the interior of the battery cell.

[0026] Second, the present utility model also provides a battery pack, which includes: a plurality of the above-mentioned battery cells.

[0027] Beneficial effects: By adopting the above-mentioned battery cells, the battery pack of the present utility model can improve its space utilization rate. Thus, without changing its own volume, its energy density can be increased, its service time can be extended or the charging frequency can be reduced. In addition, the battery pack of the present utility model has all the advantages of the above-mentioned battery cells, which will not be elaborated here. Description of the Drawings

[0028] 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 use in 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.

[0029] Figure 1 It is a partial structural schematic diagram of a battery cell according to an embodiment of the present utility model;

[0030] Figure 2 It is a partial structural schematic diagram of another battery cell according to an embodiment of the present utility model;

[0031] Figure 3 It is a cross-sectional schematic diagram of a cover plate according to an embodiment of the present utility model;

[0032] Figure 4 It is a bottom view schematic diagram of a cover plate according to an embodiment of the present utility model;

[0033] Figure 5 It is a structural schematic diagram of a cover plate according to an embodiment of the present utility model;

[0034] Figure 6 For Figure 5 the cross-sectional schematic diagram of the cover plate shown;

[0035] Figure 7 For Figure 5 the bottom view schematic diagram of the cover plate shown.

[0036] Description of the reference numerals:

[0037] 1. Housing; 101. Cover plate; 1011. Liquid injection hole; 1012. Explosion-proof valve; 1013. Sealing plate; 102. Terminal; 103. Through hole; 2. Tab; 3. Connecting piece; 301. Terminal connecting part; 302. Tab connecting part; 4. Gap. Detailed implementation manners

[0038] 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. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0039] In view of the problem that the connection manner between the connecting piece and the tab in the related art is complex and occupies a relatively large internal space of the battery cell, the present utility model provides a battery cell and a battery pack.

[0040] The following combines Figures 1 to 7 to describe the embodiments of the present utility model.

[0041] According to the embodiments of the present utility model, on the one hand, as Figures 1 to 7 shown, a battery cell is provided, including: a housing 1, an electrode assembly, and a pair of connecting pieces 3.

[0042] Specifically, openings are provided at both ends of the housing 1 and a cover plate 101 for sealing the openings, the cover plate 101 is provided with a terminal 102, and at least one cover plate 101 is provided with a through hole 103; the electrode assembly is arranged in the housing 1 and tabs 2 are provided at both ends, the tabs 2 are arranged in a staggered manner with the corresponding terminals 102, at least one tab 2 includes a body connected to the electrode assembly and a bent portion bent from the end of the body toward one side, and the bent portion is arranged corresponding to the through hole 103; a pair of connecting pieces 3 are arranged in the housing 1 and are respectively arranged at both ends of the electrode assembly, the connecting pieces 3 are used to connect the terminal 102 and its corresponding tab 2, and at least one connecting piece 3 is fixed in the space defined by the body and the bent portion and is attached to the lower surface of the bent portion.

[0043] In this embodiment, an opening communicating with the interior is provided on the housing 1, facilitating the operator to assemble relevant structures such as the electrode group into the housing 1 and improving the assembly convenience. Further, the cover plate 101 is used to seal the opening, ensuring the tightness of the battery cell, reducing the possibility of external moisture, dust and other impurities entering the interior of the battery cell, guaranteeing the cleanliness and stability of the interior environment of the battery cell, and thus being conducive to extending the service life of the battery cell. Secondly, the pole column 102 and the pole ear 2 of this embodiment are arranged in a dislocation manner, making use of the space in other directions inside the housing 1. Compared with the existing connecting piece 3 and the pole ear 2 both arranged along the axial direction of the pole column 102, the internal space of the housing 1 occupied by the connecting piece 3 and the pole ear 2 in the height direction (axial direction of the pole column) of the housing 1 in the connected state is reduced, improving the utilization rate of the internal space of the housing 1. Furthermore, the pole ear 2 is connected to the connecting piece 3 through a bending part, which can reduce the operation difficulty of connecting the pole ear 2 and the connecting piece 3 and also reduce the occupation of the internal space of the housing 1 when they are in the connected state.

[0044] It should be noted that the height direction of the above-mentioned housing 1 is the same as Figure 1 and Figure 2 the direction shown in

[0045] According to an embodiment of the present invention, as Figure 4 shown, the connecting piece 3 includes a pole column connecting part 301 connected to the pole column 102 and a pole ear connecting part 302 connected to the pole ear 2. Since the pole ear 2 and the pole column 102 in this embodiment are arranged in a dislocation manner, the connecting piece 3 is divided into the pole column connecting part 301 and the pole ear connecting part 302, which can make the position of the connecting piece 3 adapt to the pole ear 2 and the pole column 102, so that the pole ear 2 and the pole column 102 can be connected, realizing the smooth flow of current between the pole ear 2 and the pole column 102.

[0046] According to an embodiment of the present invention, the height of the body is consistent with the thickness of the pole ear connecting part 302. In this embodiment, the height of the body in the pole ear 2 is adapted to the thickness of the pole ear connecting part 302. On the one hand, the lower surface of the bending part can be closely attached to the connecting piece 3. In this way, not only the connection stability between the two can be enhanced, but also the contact resistance can be reduced, improving the transmission efficiency of current between the pole ear 2 and the pole column 102. On the other hand, it can make the structure of the connecting piece 3 and the pole ear 2 more compact in the connected state, reducing the unnecessary occupation of the internal space of the housing 1.

[0047] According to an embodiment of the present invention, as Figure 1As shown, there is a gap 4 between the tab connecting portion 302 and the inner wall of the housing 1 extending along its length direction. The bent portion is disposed on the upper surface of the tab connecting portion 302 by passing the body through the gap 4 and the through hole 103. It can be understood that since the lower surface of the bent portion needs to be in contact with the upper surface of the tab connecting portion 302, usually a channel opening suitable for the body to pass through needs to be provided on the tab connecting portion 302. However, this will make the structure of the tab connecting portion 302 relatively complex and increase the production cost in the early stage. Therefore, to solve the above problems, in this embodiment, the body passes through the gap 4 between the tab connecting portion 302 and the inner wall of the housing 1 extending along the length direction and the through hole 103 on the cover plate 101, so that no complex adjustment needs to be made to the structure of the connecting piece 3, and the structure of the connecting piece 3 itself is simplified.

[0048] According to an embodiment of the present embodiment, the body is perpendicular to the bent portion. In this embodiment, the body of the tab 2 and the bent portion of the tab 2 are perpendicular to each other, which can make the structure of the tab 2 in the housing 1 more compact, optimize the internal space of the housing 1, and improve the energy density of the battery cell.

[0049] According to an embodiment of the present invention, as Figure 1 shown, the tab 2 and the corresponding terminal 102 are arranged offset in the length direction of the housing 1. In this embodiment, the terminal 102 and the tab 2 are arranged offset in the length direction of the housing 1, which can utilize the space in the length direction inside the housing 1, and arrange the connecting piece 3 along the length direction of the housing 1 on the electrode assembly. In this way, compared with the existing connecting piece 3 and tab 2 both being arranged along the axial direction of the terminal 102, the longitudinal distance between the tab 2 and the terminal 102 will become relatively smaller, thereby reducing the occupation of the internal space of the housing 1.

[0050] It should be noted that the length direction of the above-mentioned housing 1 is Figure 1 and Figure 2 consistent with the direction shown in

[0051] According to an embodiment of the present invention, as Figure 2 shown, the connecting piece 3 is welded to the bent portion. In this embodiment, the connecting piece 3 is connected to the bent portion by welding, which can increase the connection area between the tab 2 and the connecting piece 3, reduce the resistance at the connection between the two, optimize the current conduction path, and improve the performance of the battery cell during charging and discharging.

[0052] According to an embodiment of the present invention, as Figure 5 and Figure 6As shown in the figure, the cover plate 101 is provided with a liquid injection hole 1011 and an explosion-proof valve 1012. In this embodiment, the liquid injection hole 1011 and the explosion-proof valve 1012 are arranged on the cover plate 101. On the one hand, it can make the self-structure of the cover plate 101 more compact and optimize the structural layout on the cover plate 101. On the other hand, it is convenient to add electrolyte into the battery cell, and at the same time, it can avoid excessive pressure inside the battery cell, improving the use safety of the battery cell.

[0053] According to an embodiment of the present invention, as Figure 3 shown, the cover plate 101 is provided with a sealing plate 1013, and the sealing plate 1013 is welded to the through hole 103 to seal the through hole 103. In this embodiment, the sealing plate 1013 is welded to the through hole 103 by welding. On the one hand, it can improve the connection strength between the two and reduce the possibility of the sealing plate 1013 falling off during the use of the battery cell. On the other hand, it can avoid the appearance of gaps between the sealing plate 1013 and the hole wall of the through hole 103, improving the self-sealing performance of the housing 1 and reducing the possibility of external impurities entering the battery cell.

[0054] 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.

[0055] It can be understood that by adopting the above-mentioned battery cells, the battery pack of this embodiment can improve its space utilization rate, so that without changing its own volume, it can improve its energy density, extend its use time or reduce the charging frequency. In addition, the battery pack of the present invention has all the advantages of the above-mentioned battery cells and will not be elaborated here.

[0056] It should be noted that the battery cell in this embodiment can be a blade battery. Specifically, the battery pack in this embodiment can be formed by connecting a plurality of blade batteries in series, or by connecting a plurality of blade batteries in parallel, or by a combination of series and parallel connections of a plurality of blade batteries. It can be specifically adjusted according to the actual application scenario and requirements, and the present invention does not make specific limitations in this regard.

[0057] In addition, to realize 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 selected from any suitable existing structures. To clearly and briefly illustrate the technical solutions provided in this embodiment, the above parts will not be elaborated here, and the accompanying drawings of the specification have also been correspondingly simplified. However, it should be understood that the scope of the present invention is not limited thereby.

[0058] Although 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 fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that: include: A shell, with openings and covers for sealing the openings at both ends, the covers are provided with poles, and at least one of the covers is provided with a through hole; A pole group, arranged in the shell and provided with pole ears at both ends, the pole ears are staggered with the corresponding pole column, at least one of the pole ears comprises a body connected to the pole group and a bending portion bent toward one side from the end of the body, the bending portion is arranged corresponding to the through hole; A pair of connecting plates are arranged in the shell and respectively arranged at both ends of the pole group, the connecting plates are used to connect the pole column and its corresponding pole ear, at least one of the connecting plates is fixed in the space defined by the body and the bending portion and is in contact with the lower surface of the bending portion.

2. The battery cell according to claim 1, characterized in that: The connecting piece includes a pole connecting portion connected to the pole and a tab connecting portion connected to the tab.

3. The battery cell according to claim 2, characterized in that: The height of the body is consistent with the thickness of the tab connecting portion.

4. The battery cell according to claim 2, characterized in that: A gap is left between the tab connection portion and the inner wall of the shell extending along the length direction thereof, and the bending portion passes through the body, through the gap and the through hole, and is arranged on the upper surface of the tab connection portion.

5. The battery cell according to claim 1, characterized in that: The main body and the bending portion are arranged perpendicularly.

6. The battery cell according to any one of claims 1 to 5, characterized in that: The pole lugs and the corresponding poles are staggered along the length direction of the shell.

7. The battery cell according to any one of claims 1 to 5, characterized in that: The connecting piece is connected to the bent portion by welding.

8. The battery cell according to any one of claims 1 to 5, characterized in that: The cover plate is provided with a liquid injection hole and an explosion-proof valve.

9. The battery cell according to any one of claims 1 to 5, characterized in that: A sealing plate is disposed on the cover plate, and the sealing plate is welded to the through hole and seals the 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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