Soft package battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, and particularly discloses a soft package battery cell and a battery pack, the soft package battery cell comprises a battery cell body, a positive tab and a negative tab, the battery cell body is provided with a first side, the positive tab and the negative tab are both arranged on the first side and are both connected with the battery cell body, the positive tab and the negative tab are used for current conduction, and the first side is provided with a second side. The positive tab and the negative tab are arranged on the same side, so that the distance between the positive tab and the negative tab can be shortened, the electron moving path between the positive tab and the negative tab can be shortened, the internal resistance can be reduced, the heat productivity can be reduced, meanwhile, the length of the battery cell body is L, the length of the positive tab and the length of the negative tab are both a, 4a > L > 2a, L > = 500 mm in the embodiment, and compared with a conventional positive tab and a conventional negative tab, L > = 500 mm in the embodiment. The positive tab and the negative tab are longer, the current-carrying capacity is higher, and fast charging is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and particularly refers to a soft-pack battery cell and a battery pack. Background Art

[0002] With the continuous expansion of the power battery market, especially the rapid development of the electric vehicle industry, the demand for power batteries has increased sharply. Fast charging technology is regarded as the key technology to solve the anxiety of energy replenishment for electric vehicles. Compared with traditional charging methods, fast charging technology greatly shortens the charging time, better meets the user's needs for convenience and high efficiency, and also promotes the development of new energy vehicles.

[0003] In the prior art, a utility model patent with a publication number of CN117154281 A discloses a battery liquid cooling system, a battery cell module and a battery pack. In this system, a horizontal liquid cooling plate is arranged below each layer of battery cells, and side liquid cooling plates are arranged on both sides, forming a receiving groove with two side walls and a bottom wall to hold the battery cells. Since this design can achieve the cooling of three sides of the battery cells, it has a relatively high cooling efficiency.

[0004] However, although the existing liquid cooling technology improves the cooling efficiency of the battery cells, there are still some problems in actual applications. The positive and negative electrode tabs of traditional soft-pack battery cells are respectively arranged at both ends of the short sealing edge of the battery cell, which results in a relatively long internal electron movement path of the battery cell, a relatively large internal resistance of the battery cell, and relatively high heat generation during fast charging. In addition, the existing soft-pack battery cell tab has a relatively narrow width, which limits the current-carrying capacity of the battery cell tab. It is difficult to solve the heat dissipation problem under long-term fast charging, thus limiting the high-power charging and charging speed of the battery. Moreover, the flat design of the battery cells requires a horizontal liquid cooling plate to be arranged at the bottom of each layer of battery cells. Although it improves the cooling efficiency, it also limits the volume utilization rate of the battery system. Summary of the Invention

[0005] The utility model is made in consideration of the foregoing problems. The purpose of the utility model is to provide a soft-pack battery cell and a battery pack. By arranging the positive and negative electrode tabs on the long sealing edge of the battery cell body, the electron movement path between the positive electrode tab and the negative electrode tab can be shortened, the internal resistance is reduced, and the heat generation is small. Moreover, the bottom liquid cooling plate and the top liquid cooling plate are used for liquid cooling of the bottom of the battery cell stack and the positive and negative electrode tabs, and the cooling effect is good, which can effectively improve the fast charging performance of the battery cell, and at the same time, the space utilization rate of the battery system is high.

[0006] To achieve the above purpose, the utility model provides a soft-pack battery cell, including:

[0007] A battery cell body, which has a first side;

[0008] A positive electrode tab and a negative electrode tab, both of which are arranged on the first side and are both connected to the battery cell body;

[0009] Among them, the length of the battery cell body is set as L, the lengths of the positive tab and the negative tab are both set as a, and 4a > L > 2a.

[0010] For a soft-pack battery cell as described above, the battery cell body further has a second side, a first sealing edge is provided on the first side, a second sealing edge is provided on the second side, and the length of the first sealing edge is greater than the length of the second sealing edge.

[0011] For a soft-pack battery cell as described above, L ≥ 500 mm.

[0012] A battery pack includes:

[0013] The soft-pack battery cell as described above;

[0014] An installation bracket, and a plurality of the soft-pack battery cells can be stacked in the installation bracket to form a battery cell stack, and a clamping portion is provided on the outer side of the installation bracket;

[0015] A box body, in which a slideway is arranged in the vertical direction, and a plurality of the battery cell stacks can be installed in the box body, the clamping portion can be snapped into the slideway and can move along the arrangement direction of the slideway.

[0016] For a battery pack as described above, the box body includes side longitudinal beams, side cross beams, internal longitudinal beams and internal cross beams. The side longitudinal beams and the side cross beams enclose an installation area, the internal longitudinal beams and the internal cross beams enclose a frame, the internal longitudinal beams and the internal cross beams are arranged alternately in the frame and enclose four installation areas with the frame, and four groups of the battery cell stacks can be respectively installed in the four installation areas.

[0017] For a battery pack as described above, the slideways are provided on both the side longitudinal beams and the internal longitudinal beams, the clamping portions are provided on both symmetric sides of the installation bracket, and the two clamping portions can be respectively snapped into two symmetrically arranged slideways.

[0018] For a battery pack as described above, the installation bracket is a metal bracket, two of the soft-pack battery cells are provided in each metal bracket, both ends of the soft-pack battery cell are bonded to the two inner sides of the metal bracket, and a foam is provided between the two soft-pack battery cells.

[0019] For a battery pack as described above, positioning pins are provided at the four corners of the top of the metal bracket, positioning holes are provided at the four corners of the bottom of the metal bracket, and the positioning pins can be inserted into the positioning holes to connect two adjacent metal brackets arranged in the vertical direction.

[0020] A battery pack as described above further includes a plastic bracket which is located on the battery cell stack and is used to provide support for the positive electrode tab and the negative electrode tab.

[0021] A battery pack as described above further includes a bottom liquid cooling plate and a top liquid cooling plate. The bottom liquid cooling plate is located at the bottom of the battery cell stack, and the top liquid cooling plate is located at the top of the battery cell stack. The top liquid cooling plate is connected to the positive electrode tab and the negative electrode tab through a heat-conducting adhesive.

[0022] The present utility model has the following beneficial effects:

[0023] 1. Both the positive electrode tab and the negative electrode tab of the soft-pack battery cell are arranged on the first sealing edge, which can shorten the electron movement path between the positive electrode tab and the negative electrode tab, thereby reducing the internal resistance and heat generation.

[0024] 2. The lengths of both the positive electrode tab and the negative electrode tab are greater than one-fourth of the length of the battery cell body, and the length of the battery cell body is greater than or equal to 500 mm. Then, both the positive electrode tab and the negative electrode tab are relatively long, and their current-carrying capacity is strong, which can effectively improve the fast charging performance of the battery cell.

[0025] 3. The quick assembly of the soft-pack battery cell can be realized through the cooperation of the clamping part of the metal bracket and the slideway in the box body. It realizes module-free, which can save the space of the battery system and improve the space utilization rate of the battery system.

[0026] 4. The bottom liquid cooling plate and the top liquid cooling plate can perform liquid cooling on the battery cell stack and the positive and negative electrode tabs in multiple aspects, effectively improving the cooling effect. Description of the Drawings

[0027] Figure 1 is a schematic structural diagram of the soft-pack battery cell in the embodiment;

[0028] Figure 2 is a schematic overall structural diagram of the battery pack in the embodiment;

[0029] Figure 3 is Figure 2 a partial structural schematic diagram of the cross-sectional view at A-A;

[0030] Figure 4 is a schematic structural diagram of the battery cell stack in the embodiment;

[0031] Figure 5 is a schematic structural diagram of the side longitudinal beam in the embodiment;

[0032] Figure 6 is a side view of the mounting bracket in the embodiment;

[0033] Figure 7 is a schematic bottom structural diagram of the mounting bracket in the embodiment.

[0034] In the figure:

[0035] 1. Soft-pack battery cell; 11. Battery cell body; 12. Positive electrode tab; 13. Negative electrode tab; 2. Mounting bracket; 21. Clamping part; 22. Positioning hole; 23. Positioning pin; 3. Box body; 31. Slideway; 32. Side longitudinal beam; 33. Side cross beam; 34. Internal longitudinal beam; 35. Internal cross beam; 4. Plastic bracket; 5. Bottom liquid cooling plate. Specific embodiments

[0036] The following are specific embodiments of the present invention and, in conjunction with the accompanying drawings, further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0037] As Figure 1 shown, a soft-pack battery cell includes a battery cell body 11, a positive electrode tab 12, and a negative electrode tab 13.

[0038] Among them, the battery cell body 11 has a first side, and both the positive electrode tab 12 and the negative electrode tab 13 are arranged on the first side and are both connected to the battery cell body 11. The positive electrode tab 12 and the negative electrode tab 13 are used for current conduction. Their placement on the same side can shorten the distance between the two, thereby shortening the electron movement path between the positive electrode tab 12 and the negative electrode tab 13, reducing the internal resistance and heat generation. At the same time, the length of the battery cell body 11 is set to L, and the lengths of both the positive electrode tab 12 and the negative electrode tab 13 are set to a, where 4a > L > 2a. In this embodiment, L ≥ 500 mm. Compared with conventional positive electrode tabs 12 and negative electrode tabs 13, the positive electrode tabs 12 and negative electrode tabs 13 in this application are longer and have stronger current-carrying capacity, facilitating fast charging.

[0039] Specifically, the battery cell body 11 also has a second side. A first sealing edge is provided on the first side, and a second sealing edge is provided on the second side. The length of the first sealing edge is greater than the length of the second sealing edge, that is, both the positive electrode tab 12 and the negative electrode tab 13 are located on the long sealing edge of the battery cell body 11, which is also beneficial to increasing the lengths of the positive electrode tab 12 and the negative electrode tab 13.

[0040] As Figure 1-7 shown, a battery pack includes the above-mentioned soft-pack battery cell 1, a mounting bracket 2, a box body 3, a plastic bracket 4, a bottom liquid cooling plate 5, and a top liquid cooling plate.

[0041] Among them, several pouch cells 1 can be stacked in the mounting bracket 2 to form a cell stack. In this embodiment, the mounting bracket 2 is a metal bracket. Two pouch cells 1 are provided in each metal bracket. Both ends of the pouch cell 1 are bonded to the inner sides of the metal bracket. A clamping portion 21 is provided on the outer side of the metal bracket. A slideway is arranged vertically in the box body 3. Multiple cell stacks can be installed in the box body 3. The clamping portion 21 can be inserted into the slideway 31 and can move along the arrangement direction of the slideway 31. After the pouch cell 1 is installed, the cell stack can be quickly installed into the box body 3 through the cooperation of the clamping portion 21 and the slideway 31. The assembly is convenient, and the module-free design can be realized, which can save the space in the box body 3 and improve its utilization rate.

[0042] In this embodiment, the clamping portion 21 can be a metal elastic sheet. The slideway 31 is only provided with openings at the upper and lower ends and in the middle. After the metal elastic sheet is pressed into the slideway 31, it abuts against the inner wall of the slideway 31 through its elastic restoring force, thereby realizing its clamping and positioning. At the same time, under the drive of force, it can slide up and down in the slideway 31, thereby driving the cell stack to move up and down. The installation of the cell stack is realized by moving downward, and the cell stack can be taken out by moving upward.

[0043] Specifically, positioning pins 23 are provided at the four corners of the top of the metal bracket, and positioning holes 22 are provided at the four corners of the bottom of the metal bracket. The positioning pins 23 can be inserted into the positioning holes 22 to connect two adjacent metal brackets arranged vertically. That is, two cell stacks stacked up and down can be installed and positioned through the pin-hole structure, avoiding their shaking and not affecting their up and down movement.

[0044] Specifically, the box body 3 includes side longitudinal beams 32, side cross beams 33, internal longitudinal beams 34 and internal cross beams 35. The side longitudinal beams 32 and the side cross beams 33 enclose an installation area. The internal longitudinal beams 34 and the internal cross beams 35 enclose a frame. The internal longitudinal beams 34 and the internal cross beams 35 are arranged alternately in the frame and enclose four installation areas with the frame. Four groups of cell stacks can be respectively installed in the four installation areas. Each group of cell stacks includes one or more cell stacks. The internal longitudinal beams 34 and the internal cross beams 35 are used for area division to increase the installation quantity of the cell stacks, thereby increasing the energy storage.

[0045] In order to realize the relatively stable installation and positioning of the mounting bracket 2, slideways 31 are provided on both the side longitudinal beams 32 and the internal longitudinal beams 34. Clamping portions 21 are provided on both symmetric sides of the mounting bracket 2. The two clamping portions 21 can be respectively inserted into the two symmetrically arranged slideways 31, that is, the two sides of the mounting bracket 2 are clamped and positioned at the same time to ensure the stability of its movement and avoid shaking.

[0046] In this embodiment, there is a foam between two soft-pack battery cells 1 of the same metal bracket. This foam can absorb the displacement of the two soft-pack battery cells 1 and prevent them from squeezing each other rigidly.

[0047] Among them, the plastic bracket 4 is located on the battery cell stack and is used to provide support for the positive electrode tab 12 and the negative electrode tab 13. At the same time, the plastic bracket 4 can also fill the space inside the box body 3 to prevent the battery cell stack from moving.

[0048] Among them, the bottom liquid cooling plate 5 is located at the bottom of the battery cell stack, and the top liquid cooling plate is located at the top of the battery cell stack. The top liquid cooling plate is connected to the positive electrode tab 12 and the negative electrode tab 13 through a heat-conducting adhesive, realizing liquid cooling of the battery cell stack, the positive electrode tab 12 and the negative electrode tab 13 from multiple aspects, and can effectively improve the cooling effect.

[0049] The technical solutions of the present utility model have been described in detail above in conjunction with the accompanying drawings. The described embodiments are used to help understand the idea of the present utility model. The specific embodiments described herein are only illustrative examples of the spirit of the present utility model. Those skilled in the technical field to which the present utility model belongs can make various modifications or supplements to the described specific embodiments or use similar methods to replace them, but will not deviate from the spirit of the present utility model or exceed the scope defined by the appended claims.

[0050] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present utility model are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If this specific posture changes, then the directional indications will also change accordingly.

[0051] In addition, in the present utility model, descriptions such as "first", "second", "one", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present utility model, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0052] In the present utility model, unless otherwise clearly specified and limited, terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and can be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0053] In addition, the technical solutions between the various embodiments of the present utility model can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

Claims

1. A soft-pack battery cell, characterized in that, Comprising: A battery cell body having a first side; A positive electrode tab and a negative electrode tab, both of which are arranged on the first side and are both connected to the battery cell body; Wherein, the length of the battery cell body is set as L, the lengths of the positive electrode tab and the negative electrode tab are both set as a, and 4a > L > 2a.

2. A soft-pack battery cell according to claim 1, characterized in that, The battery cell body further has a second side, a first sealing edge is provided on the first side, a second sealing edge is provided on the second side, and the length of the first sealing edge is greater than the length of the second sealing edge.

3. A soft-pack battery cell according to claim 1, characterized in that L ≥ 500 mm.

4. A battery pack, characterized in that, Comprising: A soft-pack battery cell according to any one of claims 1-3; An installation bracket, a plurality of the soft-pack battery cells can be stacked in the installation bracket to form a battery cell stack, and a clamping portion is provided on the outer side of the installation bracket; A box body, in which a slideway is arranged in the vertical direction, and a plurality of the battery cell stacks can be installed in the box body, and the clamping portion can be inserted into the slideway and can move along the arrangement direction of the slideway.

5. A battery pack according to claim 4, characterized in that, The box body includes side longitudinal beams, side cross beams, internal longitudinal beams and internal cross beams. The side longitudinal beams and the side cross beams enclose an installation area. The internal longitudinal beams and the internal cross beams enclose a frame. The internal longitudinal beams and the internal cross beams are arranged alternately in the frame and enclose four installation areas with the frame. Four groups of the battery cell stacks can be respectively installed in the four installation areas.

6. A battery pack according to claim 5, characterized in that, The slideways are provided on both the side longitudinal beams and the internal longitudinal beams, the clamping portions are provided on both symmetric sides of the installation bracket, and the two clamping portions can be respectively inserted into the two symmetrically arranged slideways.

7. A battery pack according to claim 4, characterized in that, The installation bracket is a metal bracket, and two of the soft-pack battery cells are arranged in each metal bracket. Both ends of the soft-pack battery cells are bonded to the inner sides of the metal bracket, and a foam is provided between the two soft-pack battery cells.

8. A battery pack according to claim 7, characterized in that, Positioning pins are provided at the four corners of the top of the metal bracket, positioning holes are provided at the four corners of the bottom of the metal bracket, and the positioning pins can be inserted into the positioning holes to connect two adjacent metal brackets arranged in the vertical direction.

9. A battery pack according to claim 7, characterized in that, It further includes a plastic bracket, and the plastic bracket is located on the battery cell stack and is used to provide support for the positive electrode tab and the negative electrode tab.

10. A battery pack according to claim 7, characterized in that, It further includes a bottom liquid cooling plate and a top liquid cooling plate. The bottom liquid cooling plate is located at the bottom of the battery cell stack, the top liquid cooling plate is located at the top of the battery cell stack, and the top liquid cooling plate is connected to the positive electrode tab and the negative electrode tab through a heat-conducting adhesive.

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