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. Wherein the battery cell comprises a shell, one side of the shell is provided with a pair of pole mounting holes, and a pole group is mounted in the shell; each pole comprises a pole body and annular flanges arranged at the two ends of the pole body, the pole bodies are arranged in the pole mounting holes in a penetrating mode, and the annular flanges are arranged at the two opposite ends of the pole mounting holes; the pair of connecting sheets are arranged on the pole group and are respectively connected with the annular flanges in the shell; wherein one of the connecting piece and the annular flange located in the shell forms a bulge, the other one forms a groove matched with the bulge, and the connecting piece and the pole are fixedly connected by inserting the bulge into the groove. According to the utility model, the bulges and the grooves are additionally arranged between the connecting sheets and the pole columns, so that an operator can quickly and accurately position the relative positions of the connecting sheets and the pole columns, the time consumed in the assembly process is reduced, and the production efficiency of subsequent battery cells is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and particularly relates 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 ear of the pole group. It ensures the smooth flow of current between the pole column and the ear, and realizes the storage and release of electrical energy of the battery cell. However, currently, directly connecting the connecting piece to the pole column makes it difficult to install the two accurately in a short time, and it is inevitable to extend the assembly time of the battery cell and reduce the production efficiency of the battery cell during the process of adjusting their positions. Summary of the Utility Model

[0003] In view of this, the utility model provides a battery cell and a battery pack to solve the problems in the related art that it is difficult to accurately position the connecting piece and the pole column, and the long assembly time affects the production efficiency of the battery cell.

[0004] In the first aspect, the utility model provides a battery cell, including:

[0005] A housing with a pair of pole column mounting holes on one side and a pole group installed inside;

[0006] A pair of pole columns, each including a column body and annular flanges arranged at both ends of the column body. The column body passes through the pole column mounting holes, and a pair of the annular flanges are arranged at opposite ends of the pole column mounting holes;

[0007] A pair of connecting pieces arranged on the pole group and respectively connected to the annular flange located inside the housing and the pole group;

[0008] Wherein, a protrusion is formed on one of the connecting piece and the annular flange located inside the housing, and a groove adapted to the protrusion is formed on the other. The connecting piece and the pole column are fixedly connected by inserting the protrusion into the groove.

[0009] Advantageous Effects: The annular flanges at both ends of the column body of the utility model cooperate with the housing to form a limiting structure for the pole column, avoiding the pole column from deviating from the preset position during the assembly or use of the battery cell, and improving the use stability and safety of the battery cell. Further, during the assembly process, only by inserting the protrusion into the groove, the relative positions of the connecting piece and the pole column can be quickly and accurately positioned, reducing the time consumed during the assembly process and improving the production efficiency of the subsequent battery cell; in addition, by welding the connection between the protrusion and the groove, the connection stability between the connecting piece and the pole column can be improved, reducing the possibility of relative displacement between the two due to vibration or external force.

[0010] In an alternative embodiment, a pair of the pole columns and a pair of the connecting pieces are arranged at intervals along the length direction of the housing, and a pair of through holes are provided between the pair of pole columns, and the pair of through holes communicate with the interior of the housing.

[0011] Beneficial effects: Since the pole columns on the housing are divided into positive pole columns and negative pole columns, by providing a pair of connecting pieces on the pole group, a complete current loop can be formed between the positive pole column and the negative pole column and the pole group, ensuring that the battery cell can perform normal electric energy storage and release operations. Further, arranging a pair of pole columns and a pair of connecting pieces at intervals along the length direction of the housing can increase the physical distance between the positive pole column and the negative pole column, reducing the probability of short circuit between the positive pole column and the negative pole column. Secondly, arranging the through holes between a pair of pole columns and connecting the through holes with the cavity of the housing can leave an operating space for the operator to install the internal structure of the housing, improving the convenience of operation.

[0012] In an alternative embodiment, a pair of the through holes are arranged at intervals along the length direction of the housing on the housing.

[0013] Beneficial effects: The utility model arranges a pair of through holes at intervals, which is convenient for the operator to observe, debug or repair the structures at different positions inside the housing, improving the convenience of operation. In addition, by arranging a pair of through holes at intervals, the structural strength of the side of the housing provided with the through holes can be ensured, avoiding the phenomenon of local stress concentration caused by concentrated openings.

[0014] In an alternative embodiment, a pair of sealing plates are provided on the housing, and the pair of sealing plates are arranged in one-to-one correspondence with the pair of through holes and seal the corresponding through holes.

[0015] Beneficial effects: By providing sealing plates on the through holes, the utility model can improve the sealing performance of the housing and reduce the possibility of external impurities entering the interior of the battery cell.

[0016] In an alternative embodiment, a liquid injection hole is provided on one of the sealing plates, and an explosion-proof valve is provided on the other sealing plate.

[0017] Beneficial effects: By arranging the liquid injection hole and the explosion-proof valve on the sealing plate, on the one hand, the self-structure of the housing can be made more compact, optimizing the structural layout on the housing; on the other hand, it is convenient to add electrolyte into the battery cell, and at the same time, the pressure inside the battery cell can be prevented from being too high, improving the use safety of the battery cell.

[0018] In an alternative embodiment, there are a pair of pole groups, each pole group is provided with pole tabs, the opposite sides of each connecting piece are respectively provided with the pole tabs, and the pole tabs are arranged in a staggered manner with the pole columns and are connected to the corresponding pole columns through the connecting pieces.

[0019] Beneficial effects: The pole post and the pole ear of the present utility model are arranged in a dislocation manner, making use of the space in the length direction inside the housing. Compared with the existing connection piece and pole ear both arranged along the axial direction of the pole post, it reduces the internal space of the housing occupied by the connection piece and the pole ear in the height direction of the housing in the connected state, improves the utilization rate of the internal space of the housing, and thus allows the battery cell to store more energy under the same volume. Secondly, by connecting the pole ear and the pole post through the connection piece, the current can be introduced into or led out of the battery cell.

[0020] In an optional embodiment, the pole ear includes a body connected to the pole group and a bent portion bent from the end of the body towards one side; the connection piece is fixed in the space defined by the body and the bent portion and fits against the lower surface of the bent portion.

[0021] Beneficial effects: The pole ear of the present utility model is connected to the connection piece through the bent portion, which can not only reduce the operation difficulty of connecting the pole ear and the connection piece, but also reduce the occupation of the internal space of the housing when they are in the connected state, allowing the battery cell to store more energy under the same volume. Further, making the connection piece fit against the lower surface of the bent portion helps to ensure good electrical contact between the connection piece and the pole ear, reduce the contact resistance, and improve the electrical conductivity of the battery cell.

[0022] In an optional embodiment, the bent portions on the opposite sides face each other and are spaced apart.

[0023] Beneficial effects: Compared with stacking the bent portions of the pole ears on the connection piece, the present utility model leaves a gap between the ends of the bent portions on the opposite sides that face each other, which can reduce the thickness of the opposite sides of the pole ear and the connection piece in the connected state, and thus reduce the occupation of the internal space of the housing and improve the energy density of the battery cell.

[0024] In an optional embodiment, the protrusion and the groove are connected by welding.

[0025] Beneficial effects: The present utility model firmly connects the protrusion and the groove together through the welding process, which can significantly improve the strength and stability of the connection part. In this way, when the battery cell is subjected to external impact or vibration, the connection part will not easily loosen or break, thereby improving the overall reliability and service life of the battery cell. In addition, by connecting the protrusion and the groove by welding, the resistance at the connection between the two can be reduced, the current conduction path can be optimized, and the performance of the battery cell during charging and discharging can be improved.

[0026] In a second aspect, the present utility model further provides a battery pack, including:

[0027] Multiple of the above-mentioned battery cells.

[0028] Beneficial effects: Since the connecting piece and the pole in the above-mentioned battery cell are fixedly connected together through the protrusions and grooves, after the battery pack of the present utility model adopts the above-mentioned battery cell, the assembly time of itself can be effectively shortened, and the production efficiency of itself can be improved. In addition, the battery pack of the present utility model has all the advantages of the above-mentioned battery cell, which will not be elaborated here. 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 to be used 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.

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

[0031] Figure 2 is Figure 1 a partial structural diagram of the battery cell shown;

[0032] Figure 3 It is a schematic cross-sectional view of a battery cell according to an embodiment of the present utility model;

[0033] Figure 4 is Figure 3 a partial enlarged view of A in;

[0034] Figure 5 It is a schematic structural diagram of another battery cell according to an embodiment of the present utility model;

[0035] Figure 6 is Figure 5 a schematic structural diagram of the battery cell without the housing installed;

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

[0037] Figure 8 It is a schematic structural diagram of a battery cell without the housing installed according to an embodiment of the present utility model.

[0038] Description of the reference numerals:

[0039] 1. Housing; 101. Through hole; 102. Sealing plate; 2. Electrode group; 201. Tab; 2011. Body; 2012. Bent portion; 3. Terminal; 301. Column body; 302. Annular flange; 3021. Protrusion; 4. Connecting piece; 401. Groove; 402. Terminal connecting portion; 403. Tab connecting portion; 404. Transition connecting portion; 5. Liquid injection hole; 6. Explosion-proof valve. Detailed implementation manners

[0040] 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. 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.

[0041] In view of the problems in the related art that it is difficult to accurately position the connecting piece and the terminal, and the assembly time is relatively long, affecting the production efficiency of the battery cell, the present utility model provides a battery cell and a battery pack.

[0042] The following combines Figures 1 to 8 to describe the embodiments of the present utility model.

[0043] According to the embodiments of the present utility model, on the one hand, as Figures 1 to 8 shown, a battery cell is provided, including: a housing 1, a pair of terminals 3, and a pair of connecting pieces 4.

[0044] Specifically, a pair of terminal mounting holes are provided on one side of the housing 1, and an electrode group 2 is installed inside; each of the pair of terminals 3 includes a column body 301 and annular flanges 302 provided at both ends of the column body 301. The column body 301 passes through the terminal mounting holes, and the pair of annular flanges 302 are provided at opposite ends of the terminal mounting holes; the pair of connecting pieces 4 are provided on the electrode group 2 and are respectively connected to the annular flange 302 and the electrode group 2 located inside the housing 1; wherein, a protrusion 3021 is formed on one of the connecting piece 4 and the annular flange 302 located inside the housing 1, and a groove 401 adapted to the protrusion 3021 is formed on the other. The connecting piece 4 and the terminal 3 are fixedly connected by inserting the protrusion 3021 into the groove 401.

[0045] At both ends of the column body 301 in this embodiment, the annular flanges 302 can form a limiting structure for the pole column 3 through cooperation with the housing 1, avoiding the pole column 3 from deviating from the preset position during the assembly or use of the battery cell, and improving the use stability and safety of the battery cell. Further, during the assembly process, only by inserting the protrusion 3021 into the groove 401, the relative positions of the connecting piece 4 and the pole column 3 can be quickly and accurately positioned, reducing the time consumed during the assembly process and improving the subsequent production efficiency of the battery cell; in addition, by welding the connection between the protrusion and the groove, the connection stability between the connecting piece 4 and the pole column 3 can also be improved, reducing the possibility of relative displacement between the two due to vibration or external force.

[0046] It should be noted that in this embodiment, the pole column 3 is arranged on the housing 1, indicating that the housing 1 in this embodiment is an integrally formed structure, which can reduce the gaps on the housing 1, improve the dust and water protection level of the battery cell and the structural strength of the housing 1 itself. In addition, since current battery cells all have a positive pole column and a negative pole column, one of the pair of pole columns 3 in this embodiment is a positive pole column and the other is a negative pole column.

[0047] It should be added that the shape of the groove 401 in this embodiment can be, but is not limited to, cylindrical and frustum-shaped. In addition, in order to improve the stability of the groove 401 and the protrusion 3021 in the connected state, the shape and size of the protrusion 3021 can be adapted to the shape and size of the groove 401.

[0048] For the sake of convenience of description, hereinafter Figure 1 the length direction, width direction and height direction of the housing are described in the directions shown.

[0049] According to an embodiment of the present invention, as Figures 5 to 8 shown, a pair of pole columns 3 and a pair of connecting pieces 4 are arranged at intervals along the length direction of the housing 1, and a pair of through holes 101 are provided between the pair of pole columns 3, and the pair of through holes 101 communicate with the inside of the housing 1. It can be understood that since the pole columns 3 on the housing 1 are divided into a positive pole column and a negative pole column, by providing a pair of connecting pieces 4 on the pole group 2, a complete current loop can be formed between the positive pole column and the negative pole column and the pole group 2, ensuring that the battery cell can perform normal electric energy storage and release operations. Further, arranging a pair of pole columns 3 and a pair of connecting pieces 4 at intervals along the length direction of the housing 1 can increase the physical distance between the positive pole column and the negative pole column, reducing the probability of short circuit between the positive pole column and the negative pole column. Secondly, by arranging the through hole 101 between the pair of pole columns 3 and connecting the through hole 101 with the cavity of the housing 1, an operation space for installing the internal structure of the housing 1 can be left for the operator, improving the operation convenience.

[0050] According to an embodiment of the present invention, as Figure 5 andFigure 7 As shown in the figure, a pair of through holes 101 are arranged on the housing 1 at intervals along the length direction of the housing 1. In this embodiment, the pair of through holes 101 are arranged at intervals, which is convenient for operators to observe, debug or repair the structures at different positions inside the housing 1, improving the convenience of operation. In addition, by arranging the pair of through holes 101 at intervals, the structural strength of the side of the housing 1 provided with the through holes 101 can be ensured, and the phenomenon of local stress concentration caused by concentrated openings can be avoided.

[0051] According to an embodiment of the present invention, as Figure 1 shown in the figure, a pair of sealing plates 102 are provided on the housing 1. The pair of sealing plates 102 are arranged in one-to-one correspondence with the pair of through holes 101 and seal the corresponding through holes 101. In this embodiment, by providing the sealing plates 102 on the through holes 101, the sealing performance of the housing 1 can be improved, and the possibility of external impurities entering the inside of the battery cell can be reduced.

[0052] According to an embodiment of the present invention, as Figure 1 shown in the figure, a liquid injection hole 5 is provided on one of the sealing plates 102, and an explosion-proof valve 6 is provided on the other sealing plate 102. In this embodiment, the liquid injection hole 5 and the explosion-proof valve 6 are arranged on the sealing plate 102. On the one hand, the self-structure of the housing 1 can be made more compact, optimizing the structural layout on the housing 1; on the other hand, it is convenient to add electrolyte into the inside of the battery cell, and at the same time, the pressure inside the battery cell can be prevented from being too high, improving the use safety of the battery cell.

[0053] According to an embodiment of the present invention, as Figures 5 to 8 shown in the figure, there are a pair of electrode groups 2. Each electrode group 2 is provided with an electrode tab 201. The opposite sides of each connecting piece 4 are respectively provided with an electrode tab 201. The electrode tab 201 is arranged in a staggered manner with the electrode post 3 and is connected to the corresponding electrode post 3 through the connecting piece 4. In this embodiment, the electrode post 3 and the electrode tab 201 are arranged in a staggered manner, making use of the space in the housing 1 in the length direction. Compared with the existing situation where the connecting piece 4 and the electrode tab 201 are both arranged along the axial direction of the electrode post 3, the internal space of the housing 1 occupied by the connecting piece 4 and the electrode tab 201 in the height direction of the housing 1 in the connected state is reduced, improving the utilization rate of the internal space of the housing 1. Furthermore, the battery cell can store more energy under the same volume. Secondly, by connecting the electrode tab 201 and the electrode post 3 through the connecting piece 4, the current can be introduced into the battery cell or led out of the battery cell.

[0054] It should be noted that, as Figures 5 to 8 shown in the figure, the positions of the pair of through holes 101 on the housing 1 respectively correspond to the positions where the pair of connecting pieces 4 are connected to the electrode tabs 201. Such a setting is convenient for operators to use the welding process to connect the connecting piece 4 and the corresponding electrode tab 201 together.

[0055] It should be noted that the tab 201 in this embodiment is integrally formed with the electrode assembly 2. In addition, the length direction and the height direction of the housing 1 in this embodiment are the same as those shown in Figure 1 .

[0056] In addition, since the tab 201 and the terminal 3 are arranged in a staggered manner, it means that the connection positions of the tab 201 and the terminal 3 with the connecting piece 4 are different. Specifically, the connecting piece 4 includes a terminal connecting portion 402 connected to the terminal 3 and a tab connecting portion 403 connected to the tab 201. A transition connecting portion 404 is formed between the tab connecting portion 403 and the terminal connecting portion 402, and the position of the through hole 101 corresponds to the position of the tab connecting portion 403. It can be understood that by forming the transition connecting portion 404 between the tab connecting portion 403 and the terminal connecting portion 402, the stress concentration phenomenon between the tab connecting portion 403 and the terminal connecting portion 402 can be avoided, ensuring the connection strength between the two.

[0057] It can be understood that since the connection position of the tab 201 and the electrode assembly 2 is higher than other positions of the electrode assembly 2, the position of the tab connecting portion 403 on the electrode assembly 2 needs to be adjusted adaptively, that is, along the height direction of the housing 1, the position of the tab connecting portion 403 is higher than the position of the terminal connecting portion 402.

[0058] According to an embodiment of the present invention, as shown in Figure 7 and Figure 8 , the tab 201 includes a body 2011 connected to the electrode assembly 2 and a bent portion 2012 bent from the end of the body 2011 toward one side; the connecting piece 4 is fixed in the space defined by the body 2011 and the bent portion 2012 and is attached to the lower surface of the bent portion 2012. The tab 201 in this embodiment is connected to the connecting piece 4 through the bent portion 2012, which can not only reduce the operation difficulty of connecting the tab 201 and the connecting piece 4, but also reduce the occupation of the internal space of the housing 1 in the connected state, enabling the battery cell to store more energy under the same volume. Further, attaching the connecting piece 4 to the lower surface of the bent portion 2012 helps to ensure good electrical contact between the connecting piece 4 and the tab 201, reduce the contact resistance, and improve the electrical conductivity of the battery cell.

[0059] According to an embodiment of the present invention, as shown in Figure 8 , the body 2011 and the bent portion 2012 are perpendicularly arranged. In this embodiment, the body 2011 of the tab 201 and the bent portion 2012 of the tab 201 are perpendicularly arranged, which can make the structure of the tab 201 in the housing 1 more compact, optimize the internal space of the housing 1, and improve the energy density of the battery cell.

[0060] In order to improve the self - structural strength of the tab 201, in a specific embodiment, the main body 2011 and the bent portion 2012 are integrally formed, and a transition fillet is provided at the connection between the main body 2011 and the bent portion 2012.

[0061] According to an embodiment of the present invention, the height of the main body 2011 is adapted to the thickness of the connecting piece 4. In this embodiment, making the height of the main body 2011 in the tab 201 adapted to the thickness of the connecting piece 4 can, on the one hand, make the lower surface of the bent portion 2012 closely fit on the connecting piece 4. Thus, not only can the connection stability between the two be enhanced, but also the contact resistance can be reduced, and the transmission efficiency of the current between the tab 201 and the terminal 3 can be improved; on the other hand, it can make the structure of the connecting piece 4 and the tab 201 more compact in the connected state, reducing the unnecessary occupation of the internal space of the housing 1.

[0062] According to an embodiment of the present invention, the bent portions 2012 on the opposite sides face each other and leave a gap. Compared with stacking the bent portions 2012 of the tabs 201 on the connecting piece 4 together, in this embodiment, leaving a gap between the ends of the bent portions 2012 on the opposite sides that face each other can reduce the thickness when the tabs 201 on the opposite sides and the connecting piece 4 are in the connected state, and thus can reduce the occupation of the internal space of the housing 1 and improve the energy density of the battery cell.

[0063] According to an embodiment of the present invention, the protrusion 3021 and the groove 401 are connected by welding. In this embodiment, the protrusion 3021 and the groove 401 are firmly connected together by the welding process, which can significantly improve the strength and stability of the connection part. In this way, when the battery cell is subjected to external impact or vibration, the connection part will not easily loosen or break, thereby improving the overall reliability and service life of the battery cell. In addition, connecting the protrusion 3021 and the groove 401 by welding can reduce the resistance at their connection, optimize the current conduction path, and improve the performance of the battery cell during charging and discharging.

[0064] According to an embodiment of the present invention, on the other hand, a battery pack is also provided, including: a plurality of the above - mentioned battery cells. Since the connecting piece 4 and the terminal 3 in the above - mentioned battery cells are fixedly connected together by the protrusion 3021 and the groove 401, the battery pack in this embodiment can shorten its own assembly time and improve its production efficiency after adopting the above - mentioned battery cells. In addition, the battery pack of the present invention has all the advantages of the above - mentioned battery cells, which will not be elaborated here.

[0065] It should be noted that the battery cells in this embodiment may be, but are not limited to, lithium-ion batteries, lithium manganate batteries, and nickel cobalt manganese ternary material batteries. Specifically, taking a lithium-ion battery as an example, the battery pack in this embodiment may be formed by connecting multiple lithium-ion batteries in series, or by connecting multiple lithium-ion batteries in parallel, or by preparing multiple lithium-ion batteries in a combination of series and parallel. Specifically, adjustments can be made according to the actual application scenarios and requirements, and the present utility model does not make specific limitations thereto.

[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, Comprising: A housing having a pair of pole post mounting holes on one side and a pole group mounted inside; A pair of pole posts, each including a post body and annular flanges provided at both ends of the post body, the post body being inserted through the pole post mounting holes, and the pair of annular flanges being provided at opposite ends of the pole post mounting holes; A pair of connecting pieces provided on the pole group and respectively connected to the annular flange located inside the housing and the pole group; Wherein, one of the connecting piece and the annular flange located inside the housing is formed with a protrusion, and the other is formed with a groove adapted to the protrusion, and the connecting piece and the pole post are fixedly connected by inserting the protrusion into the groove.

2. The battery cell according to claim 1, wherein The pair of pole posts and the pair of connecting pieces are arranged at intervals along the length direction of the housing, and a pair of through holes are provided between the pair of pole posts, and the pair of through holes communicate with the inside of the housing.

3. The battery cell according to claim 2, characterized in that, The pair of through holes are arranged on the housing at intervals along the length direction of the housing.

4. The battery cell according to claim 2, wherein, A pair of sealing plates are provided on the housing, and the pair of sealing plates are arranged in one-to-one correspondence with the pair of through holes and seal the corresponding through holes.

5. The cell according to claim 4, wherein, A liquid injection hole is provided on one of the sealing plates, and an explosion-proof valve is provided on the other sealing plate.

6. The battery cell according to any one of claims 1 to 5, characterized in that, There are a pair of the pole groups, each pole group is provided with a pole tab, the opposite sides of each connecting piece are respectively provided with the pole tab, and the pole tab is arranged offset from the pole post and is connected to the corresponding pole post through the connecting piece.

7. The battery cell according to claim 6, characterized in that, The pole tab includes a body connected to the pole group and a bent portion bent from the end of the body toward one side; the connecting piece is fixed in the space defined by the body and the bent portion and is attached to the lower surface of the bent portion.

8. The cell according to claim 7, wherein, The bent portions on the opposite sides face each other and leave a gap.

9. The battery cell according to any one of claims 1 to 5, characterized in that, The protrusion and the groove are connected by welding.

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

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