Single cell and battery pack

Abstract

The application relates to the technical field of battery cell structures and specifically provides a single battery and a battery pack, the single battery comprising a battery cell and a transition sheet; the battery cell leads out multiple tabs and gathers the tabs to form a tab group, the tab group is cut along a cutting line; the transition sheet is welded with the tab group after cutting and forms a final welding area, the distance between the final welding area and the cutting line is L1, and 0.5mm<=L1<=5mm. In the application, the tab group is cut along the cutting line, the alignment of the tabs is ensured, and the long tabs are prevented from being directly connected with the pole. In addition, the transition sheet is welded with the tab group and forms the final welding area; since the size of the tab group is limited, the distance between the final welding area and the cutting line is far, the tab group is likely to be too long and is likely to be overlapped with a fuse portion on the transition sheet or a welding area of the pole; if the distance between the two is short, the reserved area of the final welding area is small, thereby affecting the size of the final welding area and the connection strength of the transition sheet and the tab group.

Description

Technical Field

[0001] This application relates to the technical field of battery cell structure, and specifically proposes a single battery cell and a battery pack. Background Technology

[0002] In the battery cell, multiple tabs are drawn out from the electrode sheet and brought together to form a tab group, which is then electrically connected to the terminal post through an adapter plate.

[0003] However, due to the length of a single tab and the convergence path, the tab assembly may have alignment issues. Not all tabs can be perfectly stacked, but there may be some misalignment or offset. Furthermore, longer tabs may intrude into the electrode welding area on the adapter plate, causing the tab to be directly connected to the electrode, thus causing the overheating fuse function on the adapter plate to fail. Utility Model Content

[0004] The purpose of this application is to solve at least some of the technical problems mentioned above, and this purpose is achieved through the following technical solutions:

[0005] This application proposes a single-cell battery, which includes a cell and an adapter piece; wherein, the cell leads out multiple tabs, the multiple tabs are brought together to form a tab group, and the side of the tab group away from the cell is cut along a preset cutting line; the adapter piece is welded to the cut tab group to form a final welding area, and the distance between the side of the final welding area near the cutting line and the cutting line is L1, which satisfies 0.5mm≤L1≤5mm.

[0006] The technical solution proposed in this application has at least the following technical effects:

[0007] In this application, the tab assembly is cut along a preset cutting line on the side furthest from the battery cell to ensure the alignment of each tab, facilitate operation, and prevent some longer tabs from being directly connected to the terminal post, thus ensuring battery performance. Furthermore, the adapter piece is welded to the tab assembly to form a final weld area. The distance between the side of the final weld area closest to the cutting line and the cutting line is L1, satisfying 0.5mm≤L1≤5mm. Due to the limited size of the tab assembly, a large distance between the final weld area and the cutting line may result in an excessively long tab assembly, potentially overlapping with the fused portion on the adapter piece or the terminal post welding area. Conversely, a small distance between the two results in a smaller reserved area for the final weld area, affecting its size and the connection strength between the adapter piece and the tab assembly. Attached Figure Description

[0008] To better integrate the content illustrated in the accompanying drawings with the description of the specific embodiments, a brief introduction to the drawings is provided below. It is understood that the accompanying drawings mentioned below are merely schematic illustrations of some embodiments of the relevant technical solutions and the technical solutions of this application. Without creative effort, those skilled in the art can create drawings illustrating other embodiments.

[0009] Specifically, the annotations for the accompanying drawings are as follows:

[0010] Figure 1 This is a partial structural schematic diagram of a single battery cell described in some embodiments of this application;

[0011] Figure 2 This is a first isometric view of a single cell described in some embodiments of this application;

[0012] Figure 3 This is a second isometric view of a single cell described in some embodiments of this application.

[0013] Specifically, the annotations for the figure marks in the instruction manual are as follows:

[0014] 10. Battery cell; 101. Tab assembly; 102. Cutting line; 103. Final soldering area; 104. Pre-soldering area; 20. Adapter piece; 201. Fusible link; 30. Terminal post. Detailed Implementation

[0015] To make the embodiments of this application clearer, they will be described below in conjunction with the accompanying drawings. It should be understood that the content mentioned below represents only some embodiments of this application, and not all embodiments are listed exhaustively. Therefore, other embodiments that can be obtained based on the following embodiments without any inventive effort fall within the protection scope of this application.

[0016] It should be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not intended to impose strict limitations on the technical solutions unless the context clearly indicates otherwise. For example, the use of "a," "an," and "the" to modify a feature does not preclude the possibility that the feature may be plural in other embodiments.

[0017] It should be understood that the terms "comprising," "including," and "having" are open-ended, indicating the presence of the stated features but not excluding the possibility of other features in the embodiment. Similarly, the use of terms such as "first," "second," etc., to describe multiple features only indicates the distinction between one feature and another, and such terms do not imply order or sequence unless explicitly stated in the context.

[0018] It should be understood that, unless the context clearly indicates otherwise, the terms "setup," "connection," and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integrated connection; they can refer to a direct connection or an indirect connection via a medium. Those skilled in the art will understand the specific meaning of these terms in this document based on the specific circumstances.

[0019] In addition, for ease of description, the text will use terms of spatial relative relationship to describe the position of one feature relative to another feature, such as "inner", "outer", "end", "side", "upper", "middle", "lower", "high", "low", "axial", "circumferential", "radial", "horizontal", "vertical", "first direction", "second direction", etc. It can be understood that the spatial relative relationship between two features should include other specific situations besides those shown in the accompanying drawings of the specification.

[0020] The embodiments of this application are described below with reference to the accompanying drawings. It can be understood that the technical features involved in the different embodiments described below can be combined with each other as long as they do not conflict with each other.

[0021] Firstly, referring to Figures 1 to 3 This application proposes a single-cell battery, which includes a cell 10 and an adapter piece 20. The cell 10 has multiple tabs leading out, which are brought together to form a tab assembly 101. The tab assembly 101 is cut along a preset cutting line 102 on the side away from the cell 10. The adapter piece 20 is welded to the cut tab assembly 101 to form a final weld area 103. The distance between the side of the final weld area 103 closest to the cutting line 102 and the cutting line 102 is L1, and satisfies 0.5mm ≤ L1 ≤ 5mm.

[0022] In this embodiment, the tab assembly 101 is cut along a preset cutting line 102 on the side away from the cell 10 to ensure the alignment of each tab, facilitate operation, and avoid direct connection between some longer tabs and the terminal post 30, thus ensuring battery performance. Furthermore, the adapter piece 20 is welded to the tab assembly 101 to form a final weld area 103. The distance between the side of the final weld area 103 closest to the cutting line 102 and the cutting line 102 is L1, satisfying 0.5mm≤L1≤5mm. Due to the limited size of the tab assembly 101, if the distance between the final weld area 103 and the cutting line 102 is too large, the tab assembly 101 may be too long and may overlap with the fused portion 201 on the adapter piece 20 or the terminal post welding area. Conversely, if the distance is small, the area reserved for the final weld area 103 is smaller, thus affecting the size of the final weld area 103 and the connection strength between the adapter piece 20 and the tab assembly 101.

[0023] Therefore, the distance L1 between the edge of the final welding area 103 and the cutting line 102 should be appropriate. For example, L1 can be any one of 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm and 5mm or within any two of these values.

[0024] In some embodiments, refer to Figure 1Before the adapter piece 20 is welded to the tab assembly 101 to form the final weld area 103, multiple tabs in the tab assembly 101 are welded to form the pre-weld area 104.

[0025] In this embodiment, before the adapter piece 20 is welded to the tab assembly 101 to form the final welding area 103, multiple tabs are pre-welded to ensure the stability of the tab assembly 101 structure, making the connection between the tab assembly 101 and the adapter piece 20 more convenient and secure.

[0026] In some embodiments, refer to Figure 1 The pre-welding area 104 is larger than the final welding area 103, and the pre-welding area 104 overlaps with the final welding area 103 at least partially.

[0027] In this embodiment, the adapter piece 20 is welded to the pre-welding area 104 on the tab assembly 101 to form the final welding area 103, which makes the connection between the tab assembly 101 and the adapter piece 20 more convenient and firm. In addition, the pre-welding area 104 is relatively large, providing sufficient welding range for the final welding area 103.

[0028] In some embodiments, refer to Figure 1 The final welding zone 103 falls entirely within the range of the pre-welding zone 104.

[0029] In this embodiment, the final soldering area 103 falls entirely within the pre-soldering area 104, thereby further enhancing the robustness of the connection between the adapter piece 20 and the tab assembly 101.

[0030] In some embodiments, the ratio of the area of ​​the final soldering area 103 to the area of ​​the pre-soldering area 104 is greater than or equal to 0.5 and less than or equal to 0.95.

[0031] In this embodiment, the area ratio of the final soldering area 103 to the pre-soldering area 104 should not be too large; otherwise, in actual production, the final soldering area 103 may extend beyond the edge of the pre-soldering area 104, thus affecting the firmness of the connection between the adapter piece 20 and the electrode assembly 101. Conversely, the area ratio of the final soldering area 103 to the pre-soldering area 104 should not be too small; otherwise, it indicates that the area of ​​the final soldering area 103 is too small, which will also affect the firmness of the connection between the adapter piece 20 and the electrode assembly 101. Therefore, the area ratio of the final soldering area 103 to the pre-soldering area 104 should be moderate, for example, it can be any one of 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, and 0.95, or fall within the range of any two of these values.

[0032] In some embodiments, refer to Figure 1 After multiple tabs are welded and a pre-welded area 104 is formed, the cutting line 102 passes through the pre-welded area 104.

[0033] In this embodiment, the pre-welded area 104 is cut off so that the cut-off part falls off as a whole, avoiding the generation of too much debris and causing a short circuit in the battery.

[0034] In some embodiments, the extension direction of the cutting line 102 is perpendicular to the direction in which the tab is led out from the cell 10.

[0035] In this embodiment, the extension direction of the cutting line 102 is perpendicular to the lead-out direction of the tab from the battery cell 10, which makes the end of the tab assembly 101 more flush and can prevent the cutting line 102 from tilting and causing the end of the tab assembly 101 to have a sharp corner, which could easily puncture the shell.

[0036] In some embodiments, refer to Figure 1 The distance between the side of the pre-welded area 104 away from the battery cell 10 and the cutting line 102 is L2, and satisfies 1mm≤L2≤15mm.

[0037] In this embodiment, if the cutting line 102 is close to the edge of the pre-soldering area 104, there is a risk of generating more debris, which may enter the cell 10 and cause a short circuit. Furthermore, if the cutting line 102 is far from the edge of the pre-soldering area 104, that is, if the cutting line 102 is close to the edge of the final soldering area 103, the area reserved for the final soldering area 103 is smaller, which affects the size of the final soldering area 103 and consequently affects the connection strength between the adapter piece 20 and the electrode assembly 101. Therefore, the distance L2 between the edge of the pre-soldering area 104 and the cutting line 102 should be appropriate. For example, L2 can be any one of 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, and 15mm or a range between any two of these values.

[0038] In some embodiments, refer to Figure 2 The single cell also includes a terminal post 30, which is welded to the adapter piece 20 to form a terminal post 30 welding area. The distance between the terminal post 30 welding area and the cutting line 102 is L3, and satisfies 3mm≤L3≤40mm.

[0039] In this embodiment, if the distance between the cutting line 102 and the welding area of ​​the pole post 30 is too close, some of the tabs may directly overlap with the pole post 30. Conversely, if the distance between the cutting line 102 and the welding area of ​​the pole post 30 is too far, that is, if the cutting line 102 is close to the edge of the final welding area 103, the area reserved for the final welding area 103 is small, thus affecting the size of the final welding area 103 and consequently affecting the connection strength between the adapter piece 20 and the tab assembly 101. Therefore, the distance L3 between the welding area of ​​the pole post 30 and the cutting line 102 should be appropriate. For example, L3 can be any one of 3mm, 5mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, and 40mm, or fall within the range of any two of these values.

[0040] In some embodiments, refer to Figure 3 The tab assembly 101 is soldered to the side of the adapter piece 20 facing the battery cell 10, or refer to... Figure 2 The tab assembly 101 is welded to the side of the adapter piece 20 facing away from the battery cell 10.

[0041] In this embodiment, two implementation methods for connecting the tab assembly 101 to the adapter piece 20 are proposed. It should be noted that, referring to... Figure 2 and Figure 3 The terminal 30 is generally soldered to the side of the adapter piece 20 that faces away from the battery cell 10, such as... Figure 3 As shown, when the tab assembly 101 is soldered to the side of the adapter piece 20 facing the cell 10, direct connection between some tabs and the terminal post 30 can be avoided; as Figure 2 As shown, when the tab assembly 101 is welded to the side of the adapter piece 20 facing away from the cell 10, part of the thickness of the tab assembly 101 will overlap with the thickness of the terminal post 30 in the height direction of the battery, thereby reducing the space occupied by the tab assembly 101 and the terminal post 30 inside the battery casing, and thus improving the volumetric energy density.

[0042] In some embodiments, refer to Figure 2 The adapter piece 20 has a fusible part 201, and the distance between the fusible part 201 and the cutting line 102 is L4, which satisfies 1mm≤L4≤15mm.

[0043] In this embodiment, the adapter piece 20 is provided with a fuse part 201. When the battery overcurrent is large, in order to avoid thermal runaway, the fuse part 201 melts to form an open circuit. The distance L4 between the fuse part 201 and the cutting line 102 cannot be too large, otherwise the area reserved for the final soldering area 103 will be too small, thus affecting the size of the final soldering area 103 and consequently affecting the connection strength between the adapter piece 20 and the tab assembly 101. At the same time, L4 cannot be too small, otherwise some tabs may extend beyond the fuse part 201 and connect directly to the terminal post 30, causing the fuse part 201 to fail. Therefore, L4 should be moderate. For example, L4 can be any value among 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, and 15mm, or a value between any two of these values.

[0044] In some embodiments, the fusible portion 201 is a thinning structure, a widening structure, and / or a perforated structure.

[0045] In this embodiment, as Figure 2 As shown, the fuse section 201 has a narrowed structure, as... Figure 3 As shown, the fuse section 201 has a pitted structure, and in some embodiments not shown in the figure, the fuse section 201 has a thinned structure. These are all desirable implementation methods, and all can achieve the effect of fusing when the current is too large.

[0046] Secondly, embodiments of this application propose a battery pack comprising the single cell of the first aspect. Therefore, the battery pack of the second aspect possesses all the technical effects of the single cell of the first aspect, the technical effects of which will not be elaborated further.

[0047] It should be noted that the single cell in this embodiment only presents the structure related to the improvement point. Of course, it may also include other components. For example, the battery pack may also include a housing for accommodating multiple single cells, an insulating pad for isolating the single cells, etc. Other components will not be described here.

[0048] In particular, the term "and / or" in this application should be understood as follows:

[0049] In the first case, the term “and / or” between the first subject and the second subject includes any of the following meanings: (1) only the first subject; (2) only the second subject; and (3) both the first subject and the second subject.

[0050] In the second case, the term "and / or" between the last two of three or more subjects means including at least any one of the subjects. For example, "first subject, second subject and / or third subject" has the same meaning as "first subject and / or second subject and / or third subject", specifically including the following combinations: (1) only the first subject; (2) only the second subject; (3) only the third subject; (4) first subject and second subject and no third subject; (5) first subject and third subject and no second subject; (6) second subject and third subject and no first subject; and (7) first subject, second subject and third subject;

[0051] Furthermore, the character " / " in this application indicates that the objects before and after it are in an "or" relationship.

[0052] Finally, although the embodiments of this application have been described above in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the concept of this application, and such modifications and variations all fall within the scope of protection of this application.

Claims

1. A single-cell battery, characterized in that, include: The battery cell (10) has multiple tabs leading out, and the multiple tabs are gathered together to form a tab group (101). The tab group (101) is cut along a preset cutting line (102) on the side away from the battery cell (10). The adapter piece (20) is welded to the cut tab assembly (101) to form a final weld area (103). The distance between the side of the final weld area (103) close to the cut line (102) and the cut line (102) is L1, and satisfies 0.5mm≤L1≤5mm.

2. The single-cell battery according to claim 1, characterized in that, Before the adapter piece (20) is welded to the tab assembly (101) to form the final weld area (103), multiple tabs in the tab assembly (101) are welded to form a pre-weld area (104).

3. The single-cell battery according to claim 2, characterized in that, The pre-welding area (104) is larger than the final welding area (103), and the pre-welding area (104) overlaps with the final welding area (103) at least partially.

4. The single-cell battery according to claim 3, characterized in that, The final welding zone (103) falls entirely within the range of the pre-welding zone (104).

5. The single-cell battery according to claim 4, characterized in that, The ratio of the area of ​​the final weld area (103) to the area of ​​the pre-weld area (104) is greater than or equal to 0.5 and less than or equal to 0.

95.

6. The single-cell battery according to claim 3, characterized in that, After multiple tabs are welded together to form a pre-welded area (104), the cutting line (102) passes through the pre-welded area (104).

7. The single-cell battery according to claim 6, characterized in that, The extension direction of the cutting line (102) is perpendicular to the direction in which the tab is led out from the cell (10).

8. The single-cell battery according to claim 6, characterized in that, The distance between the side of the pre-welded area (104) away from the battery cell (10) and the cutting line (102) is L2, and satisfies 1mm≤L2≤15mm.

9. The single-cell battery according to claim 1, characterized in that, The single cell also includes a terminal post (30), which is welded to the adapter piece (20) to form a terminal post welding area. The distance between the terminal post welding area and the cutting line (102) is L3, and satisfies 3mm≤L3≤40mm.

10. The single-cell battery according to claim 1, characterized in that, The tab assembly (101) is welded to the side of the adapter plate (20) facing the battery cell (10), or the tab assembly (101) is welded to the side of the adapter plate (20) facing away from the battery cell (10).

11. The single-cell battery according to any one of claims 1 to 10, characterized in that, The adapter piece (20) has a fused portion (201), and the distance between the fused portion (201) and the cutting line (102) is L4, which satisfies 1mm≤L4≤15mm.

12. The single-cell battery according to claim 11, characterized in that, The fused portion (201) is a thinning structure, a widening structure, and / or a perforated structure.

13. A battery pack, characterized in that, Includes the single-cell battery as described in any one of claims 1 to 12.

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