Battery cell assembly and square battery

Abstract

The utility model provides a cell component and square battery, wherein the cell component comprises a plurality of square cells and tab connecting units, the two sides of each square cell are respectively a positive tab and a negative tab, the plurality of square cells are stacked in sequence, the tabs on the same side of the plurality of square cells are tabs with the same polarity, and the tabs on the same side of the plurality of square cells are tabs with the same polarity. The tabs on the same side are arranged in a staggered manner in the stacking direction of the square battery cells; the tab connecting unit comprises a convergence main body and a plurality of contact pieces extending along the side edge of the convergence main body, and each contact piece is connected with one corresponding tab. The overall height of the battery cell assembly can be reduced, so that the effective utilization of the battery space is facilitated.

Description

Technical Field

[0001] The utility model mainly relates to the technical field of batteries, and in particular to a battery core assembly and a square battery. Background Art

[0002] Power batteries and energy storage batteries are the two major scenarios for the application of battery technology. Energy storage batteries correspond to equipment such as solar and wind power generation, while power batteries correspond to new energy vehicles. A long time ago, the packaging types of power batteries were classified into three major forms: cylindrical, square and soft pack. Although their only difference is in shape, they actually differ in terms of technology development and application. With the continuous improvement of the requirements for the energy density of battery cells, the size planning of square battery cells is getting larger and larger, and the thickness and height of battery cells are also getting larger and larger. The increase in the thickness of the battery cells brings a series of process difficulties, such as the welding and shape control of the pole ears. Especially in the field of new energy vehicles, the increase in the height of the battery cells also brings difficulties in integration. Too high a height will affect the chassis design and ground clearance of new energy vehicles.

[0003] Existing square battery cells are generally arranged inside the battery in a "vertical pole group" manner. When the battery cell thickness is large, there are a series of process challenges in pole ear welding and shape control. In addition, when the battery cell height is also large, it is not conducive to the chassis layout of new energy vehicles or system integration in the energy storage field. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a battery cell assembly and a square battery, which can reduce the overall height of the battery cell assembly, thereby facilitating effective use of the battery space.

[0005] To solve the above technical problems, in the first aspect, the utility model provides a battery cell assembly, including: a plurality of square battery cells, each of which has a positive pole tab and a negative pole tab on both sides, and the plurality of square battery cells are stacked in sequence; the pole tabs on the same side of the plurality of square battery cells are pole tabs with the same polarity, and the pole tabs on the same side are staggered in the stacking direction of the square battery cells; a pole tab connection unit, the pole tab connection unit includes a busbar body, a plurality of contact pieces extending along the side of the busbar body, and each of the contact pieces is connected to a corresponding pole tab.

[0006] Optionally, the pole ears on the same side of the plurality of square battery cells are staggered in sequence from top to bottom or from bottom to top.

[0007] Optionally, all the contact pieces are located on the same side of the busbar body, or both sides of the busbar body have the contact pieces.

[0008] Optionally, when both sides of the busbar body have the contact pieces, the numbers of the pole tabs on the two sides of the busbar body are the same or the difference in number is equal to 1.

[0009] Optionally, the distance between the pole ear and the current collecting body increases or decreases from top to bottom.

[0010] Optionally, on the left side of the confluence body, the distance between the pole ear and the confluence body increases successively, and on the right side of the confluence body, the distance between the pole ear and the confluence body decreases successively; or on the left side of the confluence body, the distance between the pole ear and the confluence body decreases successively, and on the right side of the confluence body, the distance between the pole ear and the confluence body increases successively.

[0011] Optionally, each of the contact members has a slot, and a tab connected to each of the contact members passes through the corresponding slot.

[0012] Optionally, laser welding is adopted between the pole lug and the contact piece.

[0013] Optionally, the positive electrode tab on one side of the battery cell assembly and the negative electrode tab on the other side are both connected using the tab connection unit.

[0014] In the second aspect, the utility model provides a square battery, comprising a battery cell assembly as described in the first aspect, and also comprising a cover plate and a shell, wherein the cover plate covers the battery cell assembly and the busbar body of the tab connection unit is connected to the pole on the cover plate; the battery cell assembly is placed in the shell.

[0015] Compared with the prior art, the utility model has the following advantages: through structural optimization, a number of square battery cells are stacked in sequence, the pole ears on the same side are staggered in the stacking direction of the square battery cells, and each contact piece extending along the side of the busbar body is connected to a corresponding pole ear, so that each square battery cell can be stacked tightly together, thereby reducing the overall height of the battery cell assembly, which is beneficial to the effective use of battery space and also beneficial to system integration in the field of energy storage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present application. In the accompanying drawings:

[0017] Figure 1 This is a schematic diagram of the connection effect between a square battery cell and a tab connection unit in a battery cell assembly according to an embodiment of the utility model;

[0018] Figure 2 This is a schematic diagram of a square battery cell and a tab connection unit before connection in a battery cell assembly according to an embodiment of the present utility model;

[0019] Figure 3This is a schematic diagram of the connection between a square battery cell and a tab connection unit in a battery cell assembly according to an embodiment of the utility model;

[0020] Figure 4 This is a schematic diagram of a battery cell assembly before it is put into the shell in one embodiment of the utility model;

[0021] Figure 5 It is a schematic diagram of a square battery according to an embodiment of the present utility model.

[0022] The numbers in the figure are:

[0023] 100-square battery cell;

[0024] 101- pole ear; first pole ear 101a, second pole ear 101b;

[0025] 200-ear connection unit;

[0026] 201 - busbar body, 202 - contact piece, 202a - first contact piece, 202b - second contact piece;

[0027] 300-cover plate;

[0028] 301- pole;

[0029] 400-housing. DETAILED DESCRIPTION

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0031] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0032] It should be understood that when a component is referred to as being "on another component," "connected to another component," "coupled to another component," or "contacting another component," it may be directly on, connected to, coupled to, or contacting the other component, or there may be intervening components. In contrast, when a component is referred to as being "directly on another component," "directly connected to," "directly coupled to," or "directly contacting" another component, there are no intervening components. Similarly, when a first component is referred to as being "electrically in contact with" or "electrically coupled to" a second component, there is an electrical path between the first component and the second component that allows current to flow. The electrical path may include capacitors, coupled inductors, and / or other components that allow current to flow, even without direct contact between conductive components.

[0033] refer to Figure 1 to Figure 3 As shown. An embodiment of the utility model provides a battery cell assembly, mainly comprising: a plurality of square battery cells 100, each of which has a positive electrode tab and a negative electrode tab on both sides, the plurality of square battery cells 100 are stacked in sequence, the tabs on the same side of the plurality of square battery cells 100 are tabs 101 with the same polarity, and the tabs 101 on the same side are staggered in the stacking direction of the square battery cells 100; and also comprising a tab connection unit 200, the tab connection unit 200 includes a busbar body 201, a plurality of contact members 202 extending along the side of the busbar body 201, and each contact member 202 is connected to a corresponding tab 101.

[0034] In this embodiment, reference may be made to Figure 2As shown, taking the first pole ear 101a and the second pole ear 101b in the figure as an example, the stacking direction of the square battery cell 100 is the vertical direction Y, wherein the position of the first pole ear 101a is the position shown in L1 in the figure, and the position of the second pole ear 101b is the position shown in L2. It can be seen that the first pole ear 101a and the second pole ear 101b are not in the same vertical position, but are staggered by a certain distance. At the same time, each contact 202 of the pole ear connection unit 200 corresponds to a pole ear 101, such as the first contact 202a connected to the first pole ear 101a, and the second contact 202b connected to the second pole ear 101b. Therefore, while ensuring that each square battery cell 100 can be effectively electrically connected on the side, each square battery cell 100 can be stacked closely together, thereby reducing the overall height of the battery cell assembly, which is conducive to the effective use of the battery space.

[0035] In one example, the tabs 101 of a plurality of square battery cells 100 are staggered in sequence from top to bottom or from bottom to top.

[0036] There are two ways to stagger the pole lugs 101. One staggered setting only requires that the two pole lugs 101 adjacent to each other are staggered. However, in this staggered setting, non-adjacent pole lugs 101 may be in the same vertical position. For example, the first pole lug 101 is staggered with the second pole lug 101 in vertical position, and the second pole lug 101 is staggered with the third pole lug 101 in vertical position, but the first pole lug 101 and the third pole lug 101 may also be in the same vertical position. Therefore, in this embodiment, in order to better realize the connection between the pole lug connection unit 200 and each pole lug 101, the pole lugs 101 are staggered from top to bottom or from bottom to top in sequence, and all the pole lugs 101, whether adjacent pole lugs 101 or non-adjacent pole lugs 101, are staggered. That is, these pole lugs 101 form a staggered arrangement in the form of a ladder.

[0037] In one example, all the contact members 202 are located on the same side of the busbar body 201 , or both sides of the busbar body 201 have the contact members 202 .

[0038] In this embodiment, when all the contacts 202 are located on the same side of the busbar body 201, because the tabs 101 are arranged in a staggered manner, in order to be connected to the corresponding tabs 101, the lengths of the contacts 202 are different, and there is a longest contact 202. When the busbar body 201 has contacts 202 on both sides, the contacts 202 can be distributed on both sides to reduce the longest length of the contacts 202, so as to avoid the contact 202 being too long, which is not conducive to the installation of the tab connection unit 200.

[0039] In one example, when both sides of the busbar body 201 have the contact members 202 , the numbers of the tabs 101 on the two sides of the busbar body 201 are the same or the difference in number is equal to 1.

[0040] In this embodiment, in order to balance the number of contacts 202 on both sides of the busbar body 201 as much as possible, it is necessary to make the number of contacts 202 on both sides as equal as possible. When the number of square cells 100 is an even number, the same number of contacts 202 can be arranged on both sides of the busbar body 201. When the number of square cells 100 is an odd number, in order to keep the number of contacts 202 on both sides basically equal, it is only necessary to distribute the tabs 101 of the extra square cell 100 on either side of the busbar body 201.

[0041] In one example, the distance between the tab 101 and the current-collecting body 201 increases or decreases from top to bottom.

[0042] In this embodiment, no matter whether the distance between the tab 101 and the busbar body 201 increases or decreases from top to bottom, the contact members 202 on both sides of the busbar body 201 are basically axially symmetrical with respect to the busbar body 201. Different arrangements of the contact members 202 can adapt to different battery cell components.

[0043] In one example, on the left side of the busbar body 201, the distance between the pole ear 101 and the busbar body 201 increases successively, and on the right side of the busbar body 201, the distance between the pole ear 101 and the busbar body 201 decreases successively; or on the left side of the busbar body 201, the distance between the pole ear 101 and the busbar body 201 decreases successively, and on the right side of the busbar body 201, the distance between the pole ear 101 and the busbar body 201 increases successively. That is, the arrangement of each pole ear 101 on the left and right sides of the busbar body 201 in the battery cell assembly of this embodiment is consistent.

[0044] In one example, each contact 202 has a slot (not shown in the figure), and the tab 101 connected to each contact 202 passes through the corresponding slot.

[0045] In this embodiment, when there is no slot, the connection method between the tab 101 and the tab connection unit 200 is generally to first contact the tab 101 with the edge of the contact member 202 of the tab connection unit 200, referring to Figure 3 As shown in the figure, the tab 101 contacts the lower edge of the contact member 202, and then the tab 101 is bent and fixed to the tab connection unit 200. In this embodiment, when each contact member 202 has a slot, the tab 101 connected to each contact member 202 passes through the corresponding slot, so that during the connection stage of the tab 101 and the tab connection unit 200, the tab 101 can be passed through the slot first, which makes it easier to align the tab 101 and the contact member 202, and facilitates the subsequent fixing process.

[0046] In one example, laser welding is used between the tab 101 and the contact member 202 .

[0047] Laser welding is an efficient and precise welding method that uses a high-energy-density laser beam as a heat source. In this embodiment, different tabs 101 and contact pieces 202 are staggered by laser welding to achieve electrical connection. The shape of the tabs 101 is regular and controllable. In addition, the bending of the contact pieces 202 and the tabs 101 takes up little space, and the internal space utilization of the battery is high, thereby increasing the capacity of the square battery cell 100.

[0048] In one example, the positive electrode tab on one side of the battery cell assembly and the negative electrode tab on the other side are both connected using a tab connection unit 200 .

[0049] Based on the effectiveness of the connection between the tab 101 and the tab connection unit 200 , the positive tab on one side and the negative tab on the other side of the battery cell assembly of this embodiment are both connected using the tab connection unit 200 , which is beneficial to further improve the capacity of the battery cell assembly in the future.

[0050] The battery cell assembly provided in this embodiment has several square battery cells 100 stacked in sequence, and the pole ears 101 on the same side are staggered in the stacking direction of the square battery cells 100, and each contact piece 202 extending along the side of the busbar body 201 is connected to a corresponding pole ear 101, so that each square battery cell 100 can be stacked tightly together, thereby reducing the overall height of the battery cell assembly, which is beneficial to the effective use of battery space and also beneficial to system integration in the field of energy storage.

[0051] Another embodiment of the utility model provides a square battery, referring to Figure 4 and Figure 5 As shown, it includes a battery cell assembly, which can adopt the battery cell assembly shown in the aforementioned embodiment, and also includes a cover plate 300 and a shell 400, the cover plate 300 covers the battery cell assembly and the busbar body 201 of the pole ear connection unit 200 is connected to the pole on the cover plate 300, and the battery cell assembly is placed in the shell 400.

[0052] In this embodiment, the edge of the cover plate 300 and the mouth of the shell 400 can be laser welded. The square battery of this embodiment is highly compact, and the thickness and height of the cell assembly are basically equivalent to the thickness and height of the square battery. After the positive and negative electrodes of each square battery cell 100 are electrically connected, the value of the thickness D of the cell assembly can be set higher without affecting the shape of the tab 101 and the welding of the tab 101, and the height H of the cell assembly can be set smaller, which is conducive to system integration and improves the capacity of the cell assembly.

[0053] For other details of the modules, units, components and assemblies in this embodiment, reference may be made to the previous embodiments and will not be elaborated here.

[0054] The square battery provided in this embodiment comprises several square battery cells 100 stacked in sequence, the pole ears 101 on the same side are staggered in the stacking direction of the square battery cells 100, and each contact piece 202 extending along the side of the busbar body 201 is connected to a corresponding pole ear 101, so that each square battery cell 100 can be stacked tightly together, thereby reducing the overall height of the battery cell assembly, which is beneficial to the effective use of battery space and also beneficial to system integration in the field of energy storage.

[0055] The basic concepts have been described above. Obviously, for those skilled in the art, the above utility model disclosure is only used as an example and does not constitute a limitation of the present application. Although not explicitly stated here, those skilled in the art may make various modifications, improvements and corrections to the present application. Such modifications, improvements and corrections are suggested in the present application, so such modifications, improvements and corrections still belong to the spirit and scope of the exemplary embodiments of the present application.

[0056] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more utility model embodiments, in the above description of the embodiments of this application, multiple features are sometimes combined into one embodiment, drawing or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0057] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the claims of the present application.

Claims

1. A battery cell assembly, characterized in that: include: A plurality of square battery cells, each of which has a positive electrode tab and a negative electrode tab on both sides, and the plurality of square battery cells are stacked in sequence; The pole ears on the same side of the plurality of square battery cells are pole ears with the same polarity, and the pole ears on the same side are staggered in the stacking direction of the square battery cells; The tab connection unit comprises a busbar body and a plurality of contact pieces extending along the side of the busbar body, and each of the contact pieces is connected to a corresponding tab.

2. The battery cell assembly according to claim 1, characterized in that: The pole ears on the same side of the plurality of square battery cells are staggered in sequence from top to bottom or from bottom to top.

3. The battery cell assembly according to claim 1, characterized in that: All the contact pieces are located on the same side of the busbar body, or both sides of the busbar body are provided with the contact pieces.

4. The battery cell assembly according to claim 3, characterized in that: When both sides of the busbar body have the contact pieces, the numbers of the tabs on the two sides of the busbar body are the same or the difference in number is equal to 1.

5. The battery cell assembly according to claim 4, characterized in that: The distance between the pole ear and the current converging body increases or decreases from top to bottom.

6. The battery cell assembly according to claim 5, characterized in that: On the left side of the confluence body, the distance between the pole ear and the confluence body increases successively, and on the right side of the confluence body, the distance between the pole ear and the confluence body decreases successively; Alternatively, on the left side of the current collector body, the distance between the pole ear and the current collector body decreases in sequence, and on the right side of the current collector body, the distance between the pole ear and the current collector body increases in sequence.

7. The battery cell assembly according to claim 1, characterized in that: Each of the contact pieces has a slot, and a tab connected to each of the contact pieces passes through the corresponding slot.

8. The battery cell assembly according to claim 1, characterized in that: The pole ear and the contact piece are welded by laser.

9. The battery cell assembly according to claim 1, characterized in that: The positive electrode tab on one side of the battery cell assembly and the negative electrode tab on the other side are both connected using the tab connection unit.

10. A square battery, characterized in that: It comprises the battery cell assembly as described in any one of claims 1 to 9, and also comprises a cover plate and a shell; the cover plate covers the battery cell assembly and the busbar body of the tab connection unit is connected to the pole on the cover plate; the battery cell assembly is placed in the shell.

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