Battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery cell and a battery. Wherein the battery cell comprises a shell, one side of the shell is provided with a pair of pole columns, a pair of through holes and a liquid injection hole, the pair of through holes are located between the pair of pole columns, and the liquid injection hole is located between the pair of through holes; the plurality of pole groups are arranged in the shell, each pole group is provided with a pair of tabs, and the pair of tabs and the pair of through holes are arranged in a one-to-one correspondence manner; the tab comprises a body connected with the pole group and a bending part which is bent towards one side from the end part of the body; and the pair of connecting sheets are arranged on the plurality of pole groups and used for connecting the pole columns and the pole lugs, and the connecting sheets are fixed in a space defined by the body and the bending part and are attached to the lower surface of the bending part. The through holes and the tabs are arranged correspondingly, so that staggered arrangement of the tabs and the poles is realized, 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, and particularly relates to a battery cell and a battery pack. Background Art

[0002] The connecting piece in the battery cell is a metal sheet for connecting 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 electrical 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 complex in operation, 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 complex and occupies more internal space of the battery cell.

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

[0006] A housing, on one side of which there are provided a pair of pole columns, a pair of through holes and a liquid injection hole. The pair of through holes are located between the pair of pole columns, and the liquid injection hole is located between the pair of through holes;

[0007] A plurality of pole groups are arranged in the housing. A pair of pole ears are provided on each pole group, and the pair of pole ears are arranged in one-to-one correspondence with the pair of through holes; the pole ear includes a body connected to the pole group and a bent portion bent from the end of the body toward one side;

[0008] A pair of connecting pieces are arranged on the plurality of pole groups for connecting the pole column and the pole ear. 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.

[0009] Advantageous Effects: By providing a pair of pole columns on the housing in the utility model, it is convenient for operators to introduce or lead out current from the battery cell. Further, by arranging a pair of through holes between the pair of pole columns, on the one hand, it is convenient for operators to connect a pair of pole ears on each pole group with the corresponding connecting piece, and on the other hand, it can make the overall structure of the battery cell more compact. In addition, the through holes are arranged corresponding to the pole ears, realizing the offset arrangement of the pole ears and the pole columns, reducing the installation thickness in the connected state of the pole columns and the pole ears, and improving the utilization rate of the internal space of the housing; secondly, the pole ear is connected to the connecting piece through the bent portion, which can reduce the operation difficulty during the connection process.

[0010] In an alternative embodiment, a plurality of notches are provided on the connecting piece, and the plurality of notches are arranged at intervals in the width direction of the housing. The plurality of bending portions pass through the notches and are connected to the connecting piece.

[0011] Advantageous effects: By providing a plurality of notches on the connecting piece and allowing the plurality of bending portions to pass through the notches and be connected to the connecting piece, the present utility model can reduce the number of bends when the tabs of each electrode group are connected to the connecting piece, and reduce the complexity of the connection method between the two.

[0012] In an alternative embodiment, the plurality of electrode groups are arranged side by side in the width direction of the housing, and every two adjacent electrode groups form a pair and correspond to one notch; wherein, every two adjacent bending portions pass through the corresponding notch and are arranged back to back on the connecting piece.

[0013] Advantageous effects: By arranging the plurality of electrode groups side by side in the width direction of the housing, the present utility model can correspond to the arrangement mode of the plurality of notches. In addition, by allowing every two adjacent bending portions to pass through the corresponding notch and be arranged back to back on the connecting piece, the installation space in the width direction of the housing can be saved, the length of the through hole can be reduced, and the structural strength of the side of the housing provided with the through hole can be ensured.

[0014] In an alternative embodiment, a transition fillet is formed at the connection between the body and the bending portion, and a gap is left between the body and the side wall of the notch.

[0015] Advantageous effects: Whether a transition fillet is formed at the connection between the body and the bending portion or a certain gap is left between the body and the side wall of the notch, the structural strength of the tab can be effectively improved, and the occurrence of stress concentration and the connecting piece tearing the tab can be avoided.

[0016] In an alternative embodiment, the radius R of the transition fillet is 0.1 mm to 0.3 mm.

[0017] Advantageous effects: By setting the radius R of the transition fillet to 0.1 mm to 0.3 mm, the present utility model can ensure the structural strength of the tab, avoid the tab from being torn, and at the same time limit the radius R of the transition fillet within a relatively reasonable range to avoid occupying too much internal space of the housing.

[0018] In an alternative embodiment, the length of the gap between the side of the body facing the bending portion and the side wall of the notch is ≥ 0.2 mm.

[0019] Advantageous effects: By limiting the size of the length of the gap, on the one hand, the present utility model can avoid the interference between the tab and the connecting piece, and on the other hand, it can prevent the connecting piece from tearing the tab.

[0020] In an alternative embodiment, the connection between the body and the electrode group is biased towards one side of the electrode group, and the offset W ≤ 1 / 2T1, where T1 is the thickness of the electrode group and T1 ranges from 6 mm to 30 mm.

[0021] Advantageous effects: The present utility model sets the offset W within a reasonable range, which can ensure the flatness of the end face of the bent part after folding, omit the ear die-cutting process, reduce the usage cost and improve the production efficiency.

[0022] In an alternative embodiment, one end of the electrode group connected to the body forms a converging inclined surface, and the height h of the converging inclined surface is from 0.2 mm to 3.5 mm.

[0023] Advantageous effects: Since the height of the converging inclined surface is determined by the thickness of the electrode group, setting the height of the converging inclined surface within a reasonable range can compact the folded ear, enabling the electrode group to have a certain load-bearing capacity.

[0024] In an alternative embodiment, the thickness T2 of the bent part is from 0.1 mm to 2.5 mm.

[0025] Advantageous effects: The present utility model sets the thickness T2 of the bent part within a reasonable range, which can further save the space in the height direction of the electrode group and improve the space utilization rate of the battery cell.

[0026] In a second aspect, the present utility model also provides a battery pack, comprising: a plurality of the above-mentioned battery cells.

[0027] Advantageous effects: Since the battery pack in the present utility model adopts the above-mentioned battery cells, it can also improve its own space utilization rate. Furthermore, without changing its own volume, it can increase its energy density, extend its usage time or reduce the charging frequency. 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 herein. BRIEF 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 following drawings 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 schematic structural diagram of a battery cell according to an embodiment of the present utility model;

[0030] Figure 2 is Figure 1 a schematic cross-sectional structural diagram of the battery cell shown;

[0031] Figure 3 Schematic diagram of the structure of another kind of battery cell according to an embodiment of the present invention;

[0032] Figure 4 It is Figure 3 Schematic diagram of the structure without installing the housing;

[0033] Figure 5 Schematic diagram of the structure of yet another kind of battery cell according to an embodiment of the present invention;

[0034] Figure 6 Schematic diagram of the structure of a battery cell without installing the housing according to an embodiment of the present invention;

[0035] Figure 7 It is Figure 6 Side view schematic diagram;

[0036] Figure 8 It is Figure 7 Partial enlarged schematic diagram of A in;

[0037] Figure 9 Partial structure schematic diagram of the electrode group in an embodiment of the present invention.

[0038] Explanation of reference numerals:

[0039] 1. Housing; 101. Terminal; 102. Through hole; 103. Liquid injection hole; 104. Sealing plate; 2. Electrode group; 201. Tab; 2011. Body; 2012. Bent portion; 2013. Transition fillet; 202. Converging inclined surface; 3. Connecting piece; 301. Terminal connecting portion; 302. Tab connecting portion; 3021. Notch. Detailed implementation manners

[0040] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0041] Aiming at the problems in the related art that the connection method between the connecting piece and the tab is complex and occupies more internal space of the battery cell, the present invention provides a battery cell and a battery pack.

[0042] The following combines Figures 1 to 9 , and describes the embodiments of the present invention.

[0043] According to the embodiments of the present invention, on the one hand, as Figures 1 to 8As shown in the figure, a battery cell is provided, including: a housing 1, a plurality of electrode groups 2, and a pair of connecting pieces 3.

[0044] Specifically, on one side of the housing 1, there are provided a pair of electrode terminals 101, a pair of through holes 102, and a liquid injection hole 103. The pair of through holes 102 are located between the pair of electrode terminals 101, and the liquid injection hole 103 is located between the pair of through holes 102; the plurality of electrode groups 2 are arranged inside the housing 1, and a pair of electrode tabs 201 are provided on each electrode group 2. The pair of electrode tabs 201 are arranged in one-to-one correspondence with the pair of through holes 102; the electrode tab 201 includes a body 2011 connected to the electrode group 2 and a bent portion 2012 bent from the end of the body 2011 towards one side; the pair of connecting pieces 3 are arranged on the plurality of electrode groups 2 for connecting the electrode terminals 101 and the electrode tabs 201. The connecting piece 3 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.

[0045] It can be understood that, in order to form a complete power-on loop to smoothly introduce or draw out the current from the battery cell, generally, a pair of electrode terminals 101 need to be provided on the battery cell. Specifically, the above-mentioned pair of electrode terminals 101 are divided into a positive electrode terminal and a negative electrode terminal. Subsequently, by correctly connecting the positive electrode terminal and the negative electrode terminal to external devices through current conductors, the current can flow between the battery cell and the external devices, and the operation of introducing or drawing out the current from the battery cell can be smoothly completed. Further, in order to facilitate the operator to install or adjust the relevant structures inside the battery cell, in this embodiment, through holes 102 are provided on the housing 1, which can leave an operation space for the operator to install or adjust the internal structures of the housing 1, such as the electrode tabs 201 and the connecting pieces 3, and improve the convenience of operation. In addition, by setting the through holes 102 as a pair and arranging the pair of through holes 102 between the pair of electrode terminals 101, on the one hand, the operator can select a suitable through hole 102 to adjust the internal structure of the battery cell to ensure the flexibility of installation and maintenance; on the other hand, the overall structure of the battery cell can be made more compact.

[0046] In addition, in this embodiment, the through holes 102 are arranged corresponding to the electrode tabs 201, which means that the electrode tabs 201 and the electrode terminals 101 in the battery cell are not on the same vertical plane. Compared with the existing connecting pieces 3 and electrode tabs 201 both arranged along the axial direction of the electrode terminals 101, by utilizing the space in other directions inside the housing 1, not only can the space occupied by the electrode terminals 101 and the electrode tabs 201 in the height direction (axial direction of the electrode terminals) inside the housing 1 in the connected state be reduced, but also the utilization rate of the internal space of the housing 1 can be improved, so that the battery cell can store more energy under the same volume. Secondly, the electrode tab 201 is connected to the connecting piece 3 through the bent portion 2012, which can reduce the operation difficulty when connecting the electrode tab 201 and the connecting piece 3, and can also reduce the occupation of the internal space of the housing 1 when they are in the connected state.

[0047] It should be noted that, asFigure 1 , Figure 3 and Figure 5 As shown in Figure 1 , Figure 3 and Figure 5 , since the positive electrode post and the negative electrode post are generally arranged at intervals along the length direction of the housing 1 on the housing 1 at present, a pair of through holes 102 in this embodiment are also arranged along the length direction of the housing 1. Therefore, the pole group 2 and the pole post 101 in the misaligned state in this embodiment utilize the space in the length direction of the housing 1. Among them, the above-mentioned height direction of the housing 1, the length direction of the housing 1 are consistent with the directions shown in Figure 1 .

[0048] It can be understood that, in order to increase the operating space for the operator, a pair of through holes 102 on the housing 1 can be combined into one, and the length direction of the through hole 102 is kept consistent with the length direction of the housing 1. Further, in order to reduce the difficulty of production and manufacturing, the shape of the through hole 102 can be set as a rectangle.

[0049] Further, in order to improve the sealing performance of the housing 1, as Figure 1 shown, a pair of sealing plates 104 can be arranged on the housing 1, and the sealing plate 104 seals the through hole 102 on the housing 1.

[0050] In addition, due to the misaligned state of the pole group 2 and the pole post 101 in this embodiment, in order to adapt to this design scheme and ensure the smooth connection of the current between the pole tab 201 and the pole post 101. In one embodiment, as Figure 4 and Figure 6 shown, the connecting piece 3 includes a pole post connecting portion 301 connected to the pole post 101 and a pole tab connecting portion 302 connected to the pole tab 201, and a transition connecting portion is formed between the pole tab connecting portion 302 and the pole post connecting portion 301. Moreover, in order to avoid the problem of short circuit between a pair of pole posts 101 on the housing 1, the pair of connecting pieces 3 on the pole group 2 need to be arranged at intervals.

[0051] Since there are multiple pole groups 2 in the battery cell provided by the present utility model, in order to reduce the number of bends when the pole tabs 201 on each pole group 2 are connected to the connecting piece 3 and reduce the complexity of the connection method between the two. In one embodiment, as Figure 4 and Figure 6 shown, a plurality of notches 3021 are provided on the pole tab connecting portion 302, and a plurality of bending portions 2012 pass through the notches 3021 and are connected to the upper surface of the pole tab connecting portion 302.

[0052] Further, in order to facilitate the correspondence between the pole tabs 201 on the pole group 2 and the notches 3021 on the connecting piece 3, as Figure 4 and Figure 6As shown, a plurality of notches 3021 can be arranged at intervals in the width direction of the housing 1, and a plurality of pole groups 2 can be arranged side by side in the width direction of the housing 1. In addition, to ensure that the operator can connect the tab 201 to the connecting piece 3 through a pair of through holes 102 on the housing 1, the shape of the pair of through holes 102 can be set to a rectangle, and the length direction of the rectangle is kept consistent with the width direction of the housing 1. Among them, the width direction of the above-mentioned housing 1 is the same as Figure 1 the direction shown in

[0053] Furthermore, to save the installation space in the width direction of the housing 1, reduce the length of the through hole 102, and ensure the structural strength of the side of the housing 1 provided with the through hole 102. In the above embodiment, as Figure 4 and Figure 6 shown, two adjacent pole groups 2 are a pair and correspond to one notch 3021; among them, two adjacent bent portions 2012 pass through the corresponding notch 3021 and are arranged back to back on the connecting piece 3.

[0054] According to an embodiment of the present invention, as Figures 6 to 8 shown, a transition fillet 2013 is formed at the connection between the body 2011 and the bent portion 2012, and a gap is left between the body 2011 and the side wall of the notch 3021. Whether a transition fillet 2013 is formed at the connection between the body 2011 and the bent portion 2012, or a certain gap is left between the body 2011 and the side wall of the notch 3021, the structural strength of the tab 201 can be effectively improved, and the occurrence of stress concentration and the connecting piece 3 tearing the tab 201 can be avoided.

[0055] According to an embodiment of the present invention, as Figure 9 shown, the radius R of the transition fillet 2013 is 0.1 mm to 0.3 mm. In this embodiment, the radius R of the transition fillet 2013 is set to 0.1 mm to 0.3 mm, which can ensure the structural strength of the tab 201, avoid tearing of the tab 201, and at the same time limit the radius R of the transition fillet within a relatively reasonable range to avoid excessive occupation of the internal space of the housing 1.

[0056] According to an embodiment of the present invention, as Figure 9 shown, the length of the gap between the side of the body 2011 facing the bent portion 2012 and the side wall of the notch 3021 is ≥ 0.2 mm. In this embodiment, by limiting the size of the gap length, on the one hand, the interference between the tab 201 and the connecting piece 3 can be avoided, and on the other hand, the connecting piece 3 can be prevented from tearing the tab 201.

[0057] According to an embodiment of the present invention, as Figure 9As shown, the connection between the body 2011 and the electrode group 2 is biased towards one side of the electrode group 2, and the offset W ≤ 1 / 2T1, where T1 is the thickness of the electrode group 2, and T1 ranges from 6 mm to 30 mm. In this embodiment, setting the offset W within a reasonable range can ensure the flatness of the end face of the bent part 2012 after folding, omit the die-cutting process of the tab 201, reduce the usage cost and improve the production efficiency. It should be noted that the end face of the bent part 2012 is as shown by S in Figure 9 as follows.

[0058] According to an embodiment of the present invention, as shown in Figure 9 as follows, one end of the electrode group 2 connected to the body 2011 forms a converging inclined surface 202, and the height h of the converging inclined surface 202 is from 0.2 mm to 3.5 mm. Since the height of the converging inclined surface 202 is determined by the thickness of the electrode group 2, setting the height of the converging inclined surface 202 within a reasonable range can compact the tab 201 after folding and enable the electrode group 2 to have a certain load-bearing capacity.

[0059] It should be noted that since a converging inclined surface 202 will be formed at one end of the electrode group 2 connected to the body 2011, the position of the tab connection part 302 in the height direction of the housing 1 will be higher than the position of the terminal connection part 301 in the height direction of the housing 1.

[0060] According to an embodiment of the present invention, as shown in Figure 9 as follows, the thickness T2 of the bent part 2012 is from 0.1 mm to 2.5 mm. In this embodiment, setting the thickness T2 of the bent part 2012 within a reasonable range can further save the space in the height direction of the electrode group 2 and improve the space utilization rate of the battery cell.

[0061] In one embodiment, as shown in Figure 9 as follows, the height H of the bent part 2012 relative to the electrode group 2 is from 1.5 mm to 5 mm. It can save the space of the battery cell in the height direction of the electrode group 2 to the greatest extent while ensuring the strength and reliability of the bent part 2012, and improve the space utilization rate of the battery cell.

[0062] 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.

[0063] It can be understood that since the battery pack in this embodiment uses the above-mentioned battery cells, it can also improve its own space utilization rate. Furthermore, without changing its own volume, it can increase its energy density, extend its usage 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, which will not be elaborated here.

[0064] It should be noted that the battery cells in this embodiment can be, but are not limited to, lithium-ion batteries, lithium manganate batteries, and nickel cobalt manganese ternary material batteries. Specifically, taking the lithium-ion battery as an example, the battery pack in this embodiment can 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 series-parallel combination manner. Specifically, it can be adjusted according to the actual application scenario and requirements. In this regard, the present utility model does not make specific limitations.

[0065] In addition, 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 for the other necessary modules or components included in the battery pack, any suitable existing structure can be selected. To clearly and briefly illustrate the technical solutions provided in this embodiment, the above parts will not be elaborated herein, and the accompanying drawings of the specification have also been correspondingly simplified. However, it should be understood that the scope of the present utility model is not limited thereby.

[0066] Although the embodiments of the present utility model have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present utility model, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that, Comprising: A housing, on one side of which are provided a pair of pole posts, a pair of through holes and a liquid injection hole. The pair of through holes are located between the pair of pole posts, and the liquid injection hole is located between the pair of through holes; A plurality of electrode groups are arranged in the housing. A pair of electrode tabs are provided on each electrode group, and the pair of electrode tabs are arranged in one-to-one correspondence with the pair of through holes; The electrode tab includes a body connected to the electrode group and a bent portion bent from the end of the body toward one side; A pair of connecting pieces are arranged on the plurality of electrode groups for connecting the pole posts and the electrode tabs. The connecting piece is fixed in the space defined by the body and the bent portion and fits with the lower surface of the bent portion.

2. The battery cell according to claim 1, wherein, A plurality of notches are provided on the connecting piece, and the plurality of notches are arranged at intervals along the width direction of the housing. The plurality of bent portions pass through the notches and are connected to the connecting piece.

3. The battery cell according to claim 2, characterized in that, The plurality of electrode groups are arranged side by side along the width direction of the housing, and two adjacent electrode groups form a pair and correspond to one notch; wherein, two adjacent bent portions pass through the corresponding notches and are arranged back to back on the connecting piece.

4. The battery cell according to claim 2, characterized in that, A transition fillet is formed at the connection between the body and the bent portion, and a gap is left between the body and the side wall of the notch.

5. The battery cell according to claim 4, characterized in that, The radius R of the transition fillet is 0.1 mm to 0.3 mm.

6. The battery cell according to claim 4, characterized in that The length of the gap between the side of the body facing the bent portion and the side wall of the notch is ≥ 0.2 mm.

7. The battery cell according to any one of claims 1 to 6, characterized in that, The connection between the body and the electrode group is biased toward one side of the electrode group, and the offset W ≤ 1 / 2T1, where T1 is the thickness of the electrode group, and T1 is 6 mm to 30 mm.

8. The battery cell according to any one of claims 1 to 6, characterized in that, One end of the electrode group connected to the body forms a converging inclined surface, and the height h of the converging inclined surface is 0.2 mm to 3.5 mm.

9. The battery cell according to any one of claims 1 to 6, characterized in that, The thickness T2 of the bent portion is 0.1 mm to 2.5 mm.

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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