Battery cell connecting piece and battery pack

Abstract

The utility model belongs to the technical field of battery packs, and discloses a battery cell connecting piece and a battery pack. The battery cell connecting piece comprises a positive electrode conductive piece, a negative electrode conductive piece and a connecting piece main body, the positive conductive part is used for connecting a positive tab and comprises a first conductive part and a second conductive part which are arranged at an interval; the negative conductive piece is used for connecting a negative tab, the negative conductive piece comprises a third conductive piece and a fourth conductive piece which are arranged at an interval, and the positive conductive piece and the negative conductive piece are arranged at an interval. The connecting piece body comprises a first connecting part and a second connecting part, the first connecting part is connected to the same side of the first conductive piece and the third conductive piece, the second connecting part is connected to the second conductive piece and the fourth conductive piece, and the first connecting part is connected to the second connecting part. The battery cell connecting piece is small in internal resistance, less in heat loss and capable of improving the discharge performance of a battery pack.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packs, and in particular to a battery core connecting sheet and a battery pack. Background Art

[0002] Battery packs are widely used in various tools to provide power for the tools. At present, lithium battery packs are easy to use as a wireless battery pack, and they have the advantages of high energy density, safety, and small size, making them the preferred power source for various tools. Cylindrical cells have made significant progress in improving energy density and reducing costs. With the growing demand for power battery packs, cylindrical cells are widely used in power battery packs due to their high level of automated production and low production costs. The cell connector is a key component in the battery system. It is responsible for connecting the cell to the external circuit to ensure stable current transmission.

[0003] As the rated current of various tools increases, the battery pack needs to be able to meet a larger discharge current, which requires the structure of the battery pack to be able to adapt to its high current power supply requirements. The common battery cell connectors on the market currently have a simple structure, fewer current loops, and weak load capacity. They are not suitable for high current and high load working circuits. When the power battery pack is working at a high current, the temperature of the connector will be too high and even cause the temperature rise of the connector discharge slot to be too high and black, causing the battery pack to work poorly.

[0004] Therefore, there is an urgent need for a battery cell connecting sheet and a battery pack to solve the above problems. Utility Model Content

[0005] One purpose of the utility model is to provide a battery core connecting piece with good load capacity to avoid failure of the battery core connecting piece due to excessive temperature when a large current passes through.

[0006] To achieve this purpose, the utility model adopts the following technical solutions:

[0007] A battery cell connecting sheet, comprising:

[0008] A positive electrode conductive member, the positive electrode conductive member is used to connect the positive electrode tab, and the positive electrode conductive member includes a first conductive member and a second conductive member that are spaced apart;

[0009] A negative electrode conductive member, the negative electrode conductive member is used to connect the negative electrode tab, the negative electrode conductive member comprises a third conductive member and a fourth conductive member which are arranged at intervals, and the positive electrode conductive member is arranged at intervals from the negative electrode conductive member;

[0010] The connecting piece body includes a first connecting portion and a second connecting portion, wherein the first connecting portion is connected to the same side of the first conductive member and the third conductive member, the second connecting portion is connected to the second conductive member and the fourth conductive member, and the first connecting portion is connected to the second connecting portion.

[0011] As an optional solution for the battery cell connecting sheet, two ends of the first connecting portion are respectively flush with the outer side of the positive electrode conductive member and the outer side of the negative electrode conductive member.

[0012] As an optional solution for the battery cell connecting piece, the positive electrode conductive member is protrudingly provided on a side of the connecting piece body facing the positive electrode ear.

[0013] As an optional solution for the battery cell connecting piece, the negative electrode conductive member is protrudingly provided on a side of the connecting piece body facing the negative electrode tab.

[0014] As an optional solution for the battery cell connecting sheet, the positive electrode conductive member includes a first protrusion, which protrudes from a side of the first conductive member and the second conductive member facing the positive electrode tab, and the first protrusion is connected to the positive electrode tab.

[0015] As an optional solution for the battery cell connecting sheet, both the first conductive member and the second conductive member are provided with at least one first protrusion.

[0016] As an optional solution for the battery cell connecting sheet, the negative electrode conductive member includes a second protrusion, which protrudes from the third conductive member and the fourth conductive member on a side facing the negative electrode tab, the second protrusion is connected to the negative electrode tab, and the second protrusion is spaced apart from the center of the negative electrode tab.

[0017] As an optional solution for the battery cell connecting sheet, the third conductive member and the fourth conductive member are both provided with at least one second protrusion.

[0018] As an optional solution for the battery cell connecting sheet, the positive electrode conductive part, the negative electrode conductive part and the connecting sheet body constitute a connecting unit, and the battery cell connecting sheet includes a plurality of connecting units connected in sequence, and the first connecting part of one connecting unit is connected to the second connecting part of another connecting unit.

[0019] Another object of the present utility model is to provide a battery pack that can avoid failure of the battery pack due to excessive temperature when a large current passes through it, thereby ensuring the performance of the battery pack.

[0020] To achieve this purpose, the utility model adopts the following technical solutions:

[0021] A battery pack comprises a battery cell and the above-mentioned battery cell connecting sheet, wherein the battery cell comprises a positive electrode tab and a negative electrode tab, the positive electrode conductive member is connected to the positive electrode tab, and the negative electrode conductive member is connected to the negative electrode tab.

[0022] Beneficial effects of the utility model:

[0023] The utility model provides a battery cell connecting sheet, wherein a first conductive member, a first connecting portion and a third conductive member constitute a first conductive path connecting a positive electrode tab and a negative electrode tab, and a second conductive member, a second connecting portion and a fourth conductive member constitute a second conductive path connecting the positive electrode tab and the negative electrode tab. Compared with the prior art in which the positive electrode tab and the negative electrode tab are directly connected through a conductive member, the number of parallel circuits between the positive electrode tab and the negative electrode tab of the battery cell is increased. Under the same load condition, when multiple circuits are connected in parallel, the internal resistance is smaller, the accumulated heat and the heat loss are less, the discharge performance of the battery cell is improved, the problem of battery cell or structure failure caused by the high temperature of the battery cell connecting sheet during high-power discharge is avoided, and the safety of the battery cell is improved.

[0024] The utility model also provides a battery pack, comprising a battery cell and the above-mentioned battery cell connecting piece, the battery cell connecting piece conducts the battery cell with the electrode pole of the battery pack, and the battery pack has a strong load capacity and good discharge performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a battery cell connecting sheet provided in the first embodiment of the utility model;

[0026] Figure 2 It is a structural schematic diagram of a battery cell connecting sheet provided in the second embodiment of the present utility model;

[0027] Figure 3 It is a top view of the battery pack provided by the utility model;

[0028] Figure 4 It is a structural schematic diagram of the battery pack provided by the utility model.

[0029] In the figure:

[0030] 1. positive electrode conductive member; 11. first conductive member; 12. second conductive member; 13. first protrusion;

[0031] 2. negative electrode conductive member; 21. third conductive member; 22. fourth conductive member; 23. second protruding portion;

[0032] 3. Connecting piece body; 31. First connecting portion; 32. Second connecting portion;

[0033] 4. Circuit board connectors;

[0034] 5. Single electrode conductive member; 51. Fifth conductive member; 52. Sixth conductive member; 53. Third connecting portion; 54. Fourth connecting portion;

[0035] 100, battery cell; 110, positive electrode tab; 120, negative electrode tab;

[0036] 200. Install the support. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0038] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0040] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0041] like Figure 1 to Figure 2As shown, the cell connecting piece includes a positive conductive member 1, a negative conductive member 2 and a connecting piece body 3. The positive conductive member 1 is used to connect the positive electrode tab 110, and the positive conductive member 1 includes a first conductive member 11 and a second conductive member 12 arranged at intervals. The negative conductive member 2 is used to connect the negative electrode tab 120, and the negative conductive member 2 includes a third conductive member 21 and a fourth conductive member 22 arranged at intervals, and the positive conductive member 1 is arranged at intervals from the negative conductive member 2. The connecting piece body 3 includes a first connecting portion 31 and a second connecting portion, the first connecting portion 31 is connected to the same side of the first conductive member 11 and the third conductive member 21, the second connecting portion 32 is connected to the second conductive member 12 and the fourth conductive member 22, and the first connecting portion 31 is connected to the second connecting portion 32.

[0042] Based on the above design, the first conductive member 11, the first connecting portion 31 and the third conductive member 21 of the battery cell connector constitute a first conductive path connecting the positive electrode tab 110 and the negative electrode tab 120, and the second conductive member 12, the second connecting portion 32 and the fourth conductive member 22 constitute a second conductive path connecting the positive electrode tab 110 and the negative electrode tab 120. Compared with the prior art in which the positive electrode tab and the negative electrode tab are directly connected through a conductive member, the number of parallel circuits between the positive electrode tab 110 and the negative electrode tab 120 is increased. Under the same load, when multiple circuits are connected in parallel, the internal resistance is smaller, and the accumulated heat and heat loss are less, which is beneficial to improving the discharge performance of the battery cell, avoiding the problem of battery cell or structure failure caused by high temperature of the battery cell connecting piece during high-power discharge, and improving the safety of the battery cell.

[0043] Optionally, a side of the first conductive member 11 facing away from the second conductive member 12 and a side of the third conductive member 21 facing away from the fourth conductive member 22 are connected to the first connection portion 31. In some embodiments, a side of the second conductive member 12 facing away from the first conductive member 11 and a side of the fourth conductive member 22 facing away from the third conductive member 12 are connected to the second connection portion 32; in some other embodiments, the second connection portion 32 is connected between the second conductive member 12 and the fourth conductive member 22.

[0044] It should be noted that the first conductive member 11, the second conductive member 12, the third conductive member 21 and the fourth conductive member 22 can be set as an integral structure or a split structure. By setting the split structure, the current loop conducted from the battery cell tab can be further refined, the number of current loops can be increased, and the efficiency of conduction can be improved. Exemplarily, the shape of the positive electrode conductive member 1 and the negative electrode conductive member 2 can be set to a polygon or a circle, which can be changed according to the shape of the battery cell.

[0045] Furthermore, the two ends of the first connection part 31 are flush with the outer side of the positive electrode conductive member 1 and the outer side of the negative electrode conductive member 2, respectively, and the two ends of the second connection part 32 are flush with the inner side of the positive electrode connector 1 and the inner side of the negative electrode connector 2, respectively. That is, by increasing the area of ​​the first connection part 31 and the second connection part 32, increasing the loop area of ​​the battery cell connection sheet, and widening the width of a single loop of the battery cell connection sheet, the resistance of the current path of the battery cell connection sheet can be reduced, the power loss and heat loss on the battery cell connection sheet can be reduced, and the transmission efficiency of electric energy can be improved. In addition, by increasing the area of ​​the connection sheet body 3, the heat dissipation area can also be increased, so that the heat dissipation effect of the entire battery cell connection sheet is better. When a large current passes through the connection sheet body 3, the heat dissipation efficiency of the battery cell connection sheet is improved, and the safety hazards such as thermal failure of the battery cell, deformation of components due to excessive temperature of the battery cell connection sheet, and even smoke and fire are avoided, which greatly improves the safety of the product.

[0046] Optionally, the positive electrode conductive member 1 is protruding from a side of the connecting piece body 3 facing the positive electrode tab 110 , so as to facilitate the connection between the positive electrode conductive member 1 and the positive electrode tab 110 .

[0047] Optionally, the negative electrode conductive member 2 is protruding from a side of the connecting piece body 3 facing the negative electrode tab 120 , so as to facilitate the connection between the negative electrode conductive member 2 and the negative electrode tab 120 .

[0048] Furthermore, the positive electrode conductive member 1 includes a first protruding portion 13, the first protruding portion 13 protrudes from the first conductive member 11 and the second conductive member 12 on one side facing the positive electrode tab 110, and the first protruding portion 13 is connected to the positive electrode tab 110. In addition, the first protruding portion 13 makes it easier to use the resistance welding process, thereby improving the operability when welding the positive electrode conductive member 1 and the positive electrode tab 110.

[0049] Optionally, the first conductive member 11 and the second conductive member 12 are each provided with at least one first protrusion 13. Exemplarily, the first conductive member 11 and the second conductive member 12 are each provided with two, three, four, or other number of first protrusions 13.

[0050] Furthermore, the negative electrode conductive member 2 includes a second protrusion 23, the second protrusion 23 protrudes from the side of the third conductive member 21 and the fourth conductive member 22 facing the negative electrode tab 120, the second protrusion 23 is connected to the negative electrode tab 120, and the second protrusion 23 is spaced apart from the center of the negative electrode tab 120. For a full-tab battery cell, a protection area is set at the center of the negative electrode tab 120. When the second protrusion 23 is connected to the negative electrode tab 120, it is necessary to avoid the protection area. The second protrusion 23 is set outside the protection area, avoiding the center of the negative electrode tab 120, and connecting to the edge of the negative electrode tab 120, preventing the protection area from short circuiting or damage, which may cause the battery cell to fail directly, thereby solving the problem of the protection area. In addition, the use of the second protrusion 23 also makes it easier to use the resistance welding process, thereby improving the operability of welding the negative electrode conductive member 2 to the negative electrode tab 120.

[0051] Optionally, the third conductive member 21 and the fourth conductive member 22 are each provided with at least one second protrusion 23. Exemplarily, two, three, four, etc. second protrusions 23 may be provided on the third conductive member 21 and the fourth conductive member 22.

[0052] Furthermore, the battery cell connecting sheet also includes a single electrode conductive member 5, which is used to connect a group of positive electrode groups or a group of negative electrode groups. The single electrode conductive member 5 includes a fifth conductive member 51, a sixth conductive member 52, a third connecting portion 53 and a fourth connecting portion 54. The fifth conductive member 51 and the sixth conductive member 52 are arranged at intervals. The fifth conductive member 51 and the sixth conductive member 52 are used to connect the positive electrode tab 110 or the negative electrode tab 120. The third connecting portion 53 is connected to the side of the fifth conductive member 51 away from the sixth conductive member 52, the fourth connecting portion 54 is connected to the sixth conductive member 52, and the fifth connecting portion 53 is connected to the sixth connecting portion 54.

[0053] Embodiment 1:

[0054] like Figure 1 As shown, the positive electrode conductive member 1 and the negative electrode conductive member 2 are circular structures, and the first conductive member 11, the second conductive member 12, the third conductive member 21 and the fourth conductive member 22 are all semicircular structures and are equally divided into three parts, that is, the positive electrode conductive member 1 and the negative electrode conductive member 2 are both set as six fan-shaped structures, and a first protrusion 13 is provided on each fan-shaped structure of the positive electrode conductive member 1, and a second protrusion 23 is provided on each fan-shaped structure of the negative electrode conductive member 2. The connecting piece body 3 is a rectangular plate structure, which is surrounded by the positive electrode conductive member 1 and the negative electrode conductive member 2. In this embodiment, the current can flow from each second protrusion 23 through the connecting piece body 3 to any first protrusion 13, forming more parallel current loops, so that the internal resistance of the battery cell connecting piece is smaller, the heat loss of the battery cell connecting piece is reduced, and the discharge performance is improved.

[0055] Embodiment 2:

[0056] like Figure 2 As shown, in this embodiment, the positive conductive member 1 and the negative conductive member 2 are square structures, the first conductive member 11, the second conductive member 12, the third conductive member 21 and the fourth conductive member 22 are all integral structures, the first conductive member 11 and the second conductive member 12 are both provided with two first protrusions 13, the third conductive member 21 and the fourth conductive member 22 are both provided with two second protrusions 13, the connecting piece body 3 is a T-shaped structure, and the positive conductive member 1 and the negative conductive member 2 are respectively located at the left and right grooves of the T-shaped structure.

[0057] Embodiment three:

[0058] In order to save the space occupied by the battery cells 100, the battery cells 100 are also arranged in a staggered manner. In this case, the connecting sheet body 3 can be set as a Z-shaped structural plate, and the positive conductive member 1 and the negative conductive member 2 are respectively connected to the two grooves of the Z-shaped structural plate.

[0059] Typically, a plurality of battery cells 100 are installed in a battery pack, a plurality of positive electrode tabs 110 are arranged in parallel along a first direction to form a positive electrode group, a plurality of negative electrode tabs 120 are arranged in parallel along a first direction to form a negative electrode group, and a plurality of positive electrode groups and a plurality of negative electrode groups are alternately arranged in the battery pack in a second direction, wherein the first direction is Figure 1 The middle X direction, the second direction is Figure 1 In the Y direction, the first direction is set at an angle with the second direction, and optionally, the first direction and the second direction are perpendicular. A positive electrode conductive member 1, a negative electrode conductive member 2 and a connecting piece body 3 are set to form a connecting unit, and each battery cell connecting piece includes a plurality of connecting units connected in sequence in the first direction, a first connecting portion 31 of a connecting unit is connected to a second connecting portion 32 of another connecting unit, and a plurality of positive electrode conductive members 1 of each battery cell connecting piece are connected one-to-one with a plurality of positive electrode tabs 110 of each positive electrode group, and a plurality of negative electrode conductive members 2 of each battery cell connecting piece are connected one-to-one with a plurality of negative electrode tabs 120 of each negative electrode group, thereby realizing the connection between the battery cell connecting piece and a plurality of positive electrode tabs 110 and a plurality of negative electrode tabs 120, and improving the conductive efficiency of the battery cell connecting piece. The battery cell connecting piece can be applied to a variety of battery cell series or parallel arrangement output modes, such as single-row battery cell series arrangement, double-row battery cell parallel parallel arrangement, double-row battery cell parallel staggered arrangement, multi-series multi-parallel circuits, etc., and has a wide range of adaptability.

[0060] Furthermore, the cell connecting piece also includes a circuit board connecting piece 4, which is connected to the connecting piece body 3 and is used to connect to a BMS control board assembly to achieve control over the charging and discharging of the cell.

[0061] Optionally, the battery cell connecting piece can be integrally formed by blanking, stamping and other processes, with a mature manufacturing process and cost savings.

[0062] like Figure 3 and Figure 4 As shown, this embodiment also proposes a battery pack, including a battery cell 100 and the above-mentioned battery cell connecting sheet, the battery cell 100 includes a positive electrode tab 110 and a negative electrode tab 120, the positive electrode conductive member 1 is connected to the positive electrode tab 110, and the negative electrode conductive member 2 is connected to the negative electrode tab 120. The battery pack increases the number of current loops of the battery cell connecting sheet, expands the loop area of ​​the battery cell connecting sheet, reduces the internal resistance when a large current passes through the battery cell connecting sheet, thereby effectively reducing and reducing heat loss, and increases the heat dissipation area of ​​the battery cell connecting plate, improves the thermal failure caused by the excessive temperature of the battery cell connecting sheet, and improves the load capacity of the battery pack, and has good discharge performance.

[0063] Furthermore, the battery pack further comprises a mounting support 200, wherein the mounting support 200 forms a mounting cavity, and the plurality of battery cells 100 are fixed in the mounting cavity.

[0064] When assembling the battery pack, the specific steps are:

[0065] S1, installing the battery cell 100 into the mounting support 200;

[0066] S2, welding the battery cell connecting sheet to the battery cell 100;

[0067] S3, welding the BMS control board assembly to the circuit board connector 4.

[0068] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A battery cell connecting sheet, characterized in that: include: A positive electrode conductive member (1), the positive electrode conductive member (1) being used to connect a positive electrode tab (110), the positive electrode conductive member (1) comprising a first conductive member (11) and a second conductive member (12) which are arranged at intervals; A negative electrode conductive member (2), the negative electrode conductive member (2) being used to connect a negative electrode tab (120), the negative electrode conductive member (2) comprising a third conductive member (21) and a fourth conductive member (22) arranged at intervals, and the positive electrode conductive member (1) and the negative electrode conductive member (2) being arranged at intervals; A connecting piece body (3), the connecting piece body (3) comprising a first connecting portion (31) and a second connecting portion (32), the first connecting portion (31) being connected to the same side of the first conductive member (11) and the third conductive member (21), the second connecting portion (32) being connected to the second conductive member (12) and the fourth conductive member (22), the first connecting portion (31) being connected to the second connecting portion (32).

2. The battery cell connecting sheet according to claim 1, characterized in that: Two ends of the first connecting portion (31) are respectively flush with the outer side of the positive electrode conductive component (1) and the outer side of the negative electrode conductive component (2).

3. The battery core connecting sheet according to claim 1, characterized in that: The positive electrode conductive member (1) is protrudingly arranged on a side of the connecting piece body (3) facing the positive electrode tab (110).

4. The battery cell connecting sheet according to claim 1, characterized in that: The negative electrode conductive member (2) is protrudingly arranged on a side of the connecting piece body (3) facing the negative electrode tab (120).

5. The battery cell connecting sheet according to claim 1, characterized in that: The positive electrode conductive member (1) comprises a first protruding portion (13), the first protruding portion (13) protruding from a side of the first conductive member (11) and the second conductive member (12) facing the positive electrode tab (110), and the first protruding portion (13) is connected to the positive electrode tab (110).

6. The battery cell connecting sheet according to claim 5, characterized in that: The first conductive member (11) and the second conductive member (12) are both provided with at least one first protrusion (13).

7. The battery cell connecting sheet according to claim 1, characterized in that: The negative electrode conductive member (2) comprises a second protruding portion (23), the second protruding portion (23) protruding from a side of the third conductive member (21) and the fourth conductive member (22) facing the negative electrode tab (120), the second protruding portion (23) being connected to the negative electrode tab (120), and the second protruding portion (23) being spaced apart from the center of the negative electrode tab (120).

8. The battery cell connecting sheet according to claim 7, characterized in that: The third conductive member (21) and the fourth conductive member (22) are both provided with at least one second protruding portion (23).

9. The battery cell connecting sheet according to claim 1, characterized in that: The positive electrode conductive member (1), the negative electrode conductive member (2) and the connecting piece body (3) constitute a connecting unit, and the battery cell connecting piece comprises a plurality of connecting units connected in sequence, wherein the first connecting portion (31) of one connecting unit is connected to the second connecting portion (32) of another connecting unit.

10. A battery pack, characterized in that: The invention comprises a battery cell (100) and a battery cell connecting sheet according to any one of claims 1 to 9, wherein the battery cell (100) comprises a positive electrode tab (110) and a negative electrode tab (120), the positive electrode conductive member (1) is connected to the positive electrode tab (110), and the negative electrode conductive member (2) is connected to the negative electrode tab (120).

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