Battery and battery pack

Abstract

The battery comprises a shell, a cover plate and a battery cell, a containing cavity is formed in the shell, the cover plate is arranged on the shell in a covering mode and seals the containing cavity, the battery cell is arranged in the containing cavity and comprises a battery cell body and a tab, a pole piece is arranged in the battery cell body, one side of the pole piece extends outwards to form the tab, and the tab is arranged in the containing cavity. The extending direction of the tabs is a first direction, the direction along the plane of the tabs and perpendicular to the first direction is a second direction, the size of the tabs in the second direction is L1 mm, the size of the battery cell body in the second direction is L2 mm, and L1 is smaller than L2; a reinforcing part is arranged on the pole piece, in the first direction, the minimum distance between one end, close to the pole piece, of the reinforcing part and the pole piece is h1mm, the size of the pole piece in the first direction is Hmm, and (L1 / L2) * (h1 / H) is larger than or equal to 0.002 and smaller than or equal to 0.07. According to the utility model, the tab is not easy to tear.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery and battery pack. Background Technology

[0002] As an important component of lithium-ion batteries, the tabs are metallic conductors extending outward from the electrode plates of the battery cell. To enhance the support performance of the tabs and prevent them from easily bending during the stacking process, reinforcing ribs are usually added to the tabs to improve their support.

[0003] Currently, the common method for setting reinforcing ribs on the tabs is to press the reinforcing ribs onto the tabs using rollers with raised ridges. However, when the rollers press the reinforcing ribs onto the tabs, since the width of the tabs is smaller than the width of the electrode sheets of the battery cell, if the reinforcing ribs are too close to the electrode sheets, stress concentration is likely to occur at the corners where the tabs and electrode sheets are connected, which can easily lead to tearing at the corners where the tabs and electrode sheets are connected. Furthermore, during the hot pressing process of the battery cell, the rolling stress can also make the corners where the tabs and electrode sheets are connected prone to tearing. Utility Model Content

[0004] The primary objective of this invention is to provide a battery that prevents tearing at the corner where the tab connects to the electrode plate.

[0005] Another objective of this invention is to provide a battery pack using the aforementioned battery.

[0006] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0007] A battery having two perpendicular directions (a first direction, a second direction, and a third direction), includes a casing, a cover plate, and a battery cell. The casing has a receiving cavity, and the cover plate covers and seals the receiving cavity. The battery cell is disposed within the receiving cavity. The battery cell includes a cell body and tabs. An electrode plate is disposed within the cell body, and the tab extends outward from one side of the electrode plate. The direction in which the tab extends is the first direction, and the direction along the plane of the tab and perpendicular to the first direction is the second direction. The dimension of the tab in the second direction is L1 mm, and the dimension of the cell body in the second direction is L2 mm, where L1 < L2.

[0008] The electrode tab is provided with a reinforcing part. In the first direction, the minimum distance between the end of the reinforcing part near the electrode and the electrode is h1mm. The size of the electrode tab in the first direction is Hmm, where 0.002≤(L1 / L2)*(h1 / H)≤0.07.

[0009] This utility model also relates to a battery pack, including the battery described above.

[0010] Compared with the prior art, the battery of this utility model embodiment has the following advantages:

[0011] In this invention, the first direction is the direction in which the tab extends outward from the electrode sheet, the second direction is the direction of the width of the tab, and the third direction is the direction of the thickness of the tab. During the winding or stacking of the electrode sheet, to prevent the tab from collapsing and folding, a reinforcing portion needs to be provided on the tab. If the reinforcing portion is too close to the electrode sheet, it will cause excessive stress at the connection between the tab and the electrode sheet during the forming process, leading to tearing. Therefore, it is necessary to control the minimum distance between the reinforcing portion and the electrode sheet. Simultaneously, the tab in the second direction... When the proportion of dimension L1 to dimension L2 of the cell body in the second direction is large, the connection between the tab and the electrode is also wider and stronger, which can reduce the risk of tearing at the connection between the tab and the electrode. Therefore, satisfying 0.002≤(L1 / L2)*(h1 / H)≤0.07, the dimensions of the connection between the tab and the electrode in the second direction, as well as the distance between the reinforcing part and the electrode, can be taken into account to keep the dimensions of the tab and the electrode in the second direction, as well as the distance between the reinforcing part and the electrode, within a reasonable range, thereby ensuring the normal use of the battery and ensuring the performance of the battery. Attached Figure Description

[0012] Figure 1 This is a front view of an embodiment of the present utility model;

[0013] Figure 2 This is a side view of an embodiment of the present utility model;

[0014] Figure 3 This is a schematic diagram of the reinforcing part according to another embodiment of the present invention;

[0015] Figure 4 This is a schematic diagram of the reinforcing part in another embodiment of this utility model;

[0016] Figure 5 This is a schematic diagram of the battery pack of this utility model.

[0017] In the diagram, 100 is the casing; 200 is the cover plate; 300 is the pole; 400 is the battery cell; 500 is the battery cell body; 600 is the welding mark; 1 is the electrode sheet; 2 is the electrode tab; 3 is the reinforcing part; and 4 is the arc-shaped part. Detailed Implementation

[0018] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0019] In the description of this utility model, it should be understood that the term "comprising" as used in this specification means the presence of the stated features, integers, steps, operations, parts, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, parts, components, and / or groups thereof. It should be understood that when we say a part is "connected" to another part, it can be directly connected to the other part, or there may be intermediate parts. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items.

[0020] like Figure 1 and Figure 2 As shown, this utility model relates to a battery having three perpendicularly intersecting directions: a first direction, a second direction, and a third direction. The battery includes a casing 100, a cover plate 200, and a battery cell 400. The casing 100 has a receiving cavity, and the cover plate 200 covers the casing 100 and seals the receiving cavity. The battery cell 400 is disposed within the receiving cavity. The battery cell 400 includes a cell body 500 and tabs 2. An electrode plate 1 is disposed within the cell body 500. The tab 2 extends outward from one side of the electrode plate 1, and the direction in which the tab 2 extends is the first direction. The direction along the plane of the tab 2 and perpendicular to the first direction is the second direction. The electrode tab 2 has a dimension of L1 mm in the second direction, and the battery cell body 500 has a dimension of L2 mm in the second direction, where L1 < L2; the electrode tab 2 is provided with a reinforcing part 3, and in the first direction, the minimum distance between the end of the reinforcing part 3 near the electrode 1 and the electrode 1 is h1 mm, and the electrode tab 2 has a dimension of H mm in the first direction, where 0.002 ≤ (L1 / L2)*(h1 / H) ≤ 0.07. Specifically, the value of (L1 / L2)*(h1 / H) can be 0.006, 0.012, 0.02, 0.025, 0.035, 0.04, 0.05 or 0.06.

[0021] In this invention, the first direction is the direction in which the tab 2 extends outward from the electrode sheet 1, the second direction is the direction of the width of the tab 2, and the third direction is the direction of the thickness of the tab 2. During the winding or stacking of the electrode sheet 1, to prevent the tab 2 from collapsing and folding, a reinforcing part 3 needs to be provided on the tab 2. If the reinforcing part 3 is too close to the electrode sheet 1, it will cause excessive stress at the connection between the tab 2 and the electrode sheet 1 during the forming process, leading to tearing. Therefore, it is necessary to control the minimum distance between the reinforcing part 3 and the electrode sheet 1. Simultaneously, the tab 2 in the second direction... When the size L1 of the cell body is larger than the size L2 of the cell body in the second direction, the connection between the tab 2 and the electrode 1 is also wider and stronger, which can reduce the risk of tearing at the connection between the tab 2 and the electrode 1. Therefore, satisfying 0.002≤(L1 / L2)*(h1 / H)≤0.07, the size of the connection between the tab 2 and the electrode 1 in the second direction, as well as the distance between the reinforcing part 3 and the electrode 1, can be taken into consideration to keep the size of the tab 2 and the electrode 1 in the second direction, as well as the distance between the reinforcing part 3 and the electrode 1, within a reasonable range, thereby ensuring the normal use of the battery and ensuring the performance of the battery.

[0022] It should be explained that the battery cell 400 can be a wound battery cell or a stacked battery cell. The wound battery cell is a flat wound body formed by winding a negative electrode sheet, a first separator, a positive electrode sheet, and a second separator arranged in sequence. Both the negative electrode sheet and the positive electrode sheet have multiple tabs spaced apart on one side along the length direction. The stacked battery cell is formed by zig-folding a composite body. The composite body includes a first separator, a second separator, a positive electrode sheet, and a negative electrode sheet. Both the positive and negative electrode sheets are disposed between the first and second separators, and multiple positive and multiple negative electrode sheets are arranged alternately along the length direction of the first separator.

[0023] In some embodiments, 20mm≤L1≤150mm, 50mm≤L2≤1000mm. Specifically, the value of L1 can be 40mm, 60mm, 80mm, 100mm, 120mm or 140mm, and the value of L2 can be 100mm, 200mm, 300mm, 500mm, 700mm or 900mm, so that L1 and L2 within the above range can ensure the stability of the connection between the electrode 1 and the tab 2.

[0024] In some embodiments, 0.02≤L1 / L2≤0.4. Specifically, the value of L1 / L2 can be 0.06, 0.08, 0.16, 0.24, 0.3 or 0.35, so that L1 / L2 within the above range can ensure the stability of the connection between the electrode 1 and the tab 2.

[0025] In some embodiments, 3mm≤h1≤15mm, 10mm≤H≤50mm. Specifically, the value of h1 can be 5mm, 7mm, 9mm, 11mm or 13mm, and the value of H can be 15mm, 25mm, 35mm or 45mm, so that h1 and H within the above range can ensure the stable connection between electrode 1 and electrode tab 2.

[0026] In some embodiments, 0.06 ≤ h1 / H ≤ 0.3. Specifically, the value of h1 / H can be 0.09, 0.15, 0.2 or 0.25, so that h1 / H within the above range can ensure the stable connection between electrode 1 and electrode 2.

[0027] In some embodiments, 0.01 ≤ (L1 / L2)*(h1 / H) ≤ 0.06, so that (L1 / L2)*(h1 / H) within the above range can ensure the stability of the connection between electrode 1 and electrode 2.

[0028] In this embodiment, in the first direction, the distance between the end of the reinforcing part 3 away from the electrode 1 and the end of the tab 2 away from the electrode 1 is h2mm, where 3mm≤h2≤15mm, 0.06≤h2 / H≤0.4, and 0.1≤L1 / L2≤0.4. Specifically, the value of h2 can be 5mm, 7mm, 9mm, 11mm or 13mm, and the value of h2 / H can be 0.1, 0.16, 0.2, 0.3 or 0.35.

[0029] When h2 / H is too large, the distance between the end of the reinforcing part 3 away from the electrode 1 in the first direction and the end of the tab 2 away from the electrode 1 in the first direction is also large, so that this area is not supported by the reinforcing part 3 and is prone to bending. When h2 / H is too small, the distance between the end of the reinforcing part 3 away from the electrode 1 in the first direction and the end of the tab 2 away from the electrode 1 in the first direction is also small, making it difficult to weld with the pole post 300. Therefore, keeping h2 / H between 0.06 and 0.4 can ensure the support capacity of the tab 2, making the tab 2 less prone to bending and making the tab 2 easier to weld with the pole post 300. Meanwhile, since there is a gap between the end of the reinforcing part 3 away from the electrode 1 and the end of the tab 2 away from the electrode 1, the reinforcing part 3 cannot be too short in the first direction in order to have sufficient reinforcing capacity. This would cause the reinforcing part 3 to be closer to the electrode 1, making it easy for the tab 2 and the electrode 1 to tear during the manufacturing process. In order to ensure the stability of the tab 2 and the electrode 1, the lower limit of L1 / L2 should be larger, keeping 0.1≤L1 / L2≤0.4 to ensure the stability of the tab 2 and the electrode 1.

[0030] In this embodiment, the tab 2 has an arc-shaped transition with the electrode 1 on at least one side in the second direction, forming an arc-shaped portion 4. This avoids stress concentration at the corner between the tab 2 and the electrode 1, making it less prone to tearing between the tab 2 and the electrode 1.

[0031] Preferably, the radius of the arc-shaped portion 4 is e mm, where 1 mm ≤ e ≤ 10 mm, and 0.002 ≤ (L1 / L2)*(h1 / H) ≤ 0.06. Specifically, the value of e can be 2 mm, 4 mm, 6 mm, or 8 mm.

[0032] Since the arc-shaped part 4 itself has the function of releasing stress and can reduce stress concentration, when the arc of the arc-shaped part 4 is large, it can release more stress. Therefore, when 1mm≤e≤10mm, the upper limit of (L1 / L2)*(h1 / H) can be reduced so that 0.002≤(L1 / L2)*(h1 / H)≤0.06, which can ensure the stability of the connection between the tab 2 and the electrode 1.

[0033] In this embodiment, the tab 2 is provided with a plurality of reinforcing portions 3 spaced apart and evenly distributed along the second direction, and each reinforcing portion 3 extends along the first direction. The distance between two adjacent reinforcing portions 3 in the second direction is L3mm, where 0.01≤L3 / L1≤0.07, 0.005≤(L1 / L2)*(h1 / H)≤0.05, 20mm≤L1≤150mm, and 1mm≤L3≤4mm. Specifically, the value of L3 can be 1.5mm, 2mm, 2.5mm, or 3mm.

[0034] On the tab 2, the more numerous and densely arranged the reinforcing parts 3 are, the easier it is for the tab 2 and the electrode sheet 1 to tear when the reinforcing parts 3 are pressed out. Therefore, the distance h1 between the reinforcing parts 3 and the electrode sheet 1 needs to be larger to avoid tearing. If the number of reinforcing parts 3 is smaller and the arrangement is more sparse, it is less likely for the tab 2 and the electrode sheet 1 to tear when the reinforcing parts 3 are pressed out. Therefore, the distance h1 between the reinforcing parts 3 and the electrode sheet 1 can be smaller. Thus, 0.01≤L3 / L1≤0.07, 0.005≤(L1 / L2)*(h1 / H)≤0.05, 20mm≤L1≤150mm, and 1mm≤L3≤4mm are used to provide better support for the tab 2 while preventing tearing between the tab 2 and the electrode sheet 1.

[0035] In other embodiments, in a first direction, the reinforcing portion 3 extends from one end of the tab 2 to the other end, and the direction of extension of the reinforcing portion 3 is inclined relative to the first direction.

[0036] That is, the plurality of reinforcing parts 3 can also be arranged obliquely on the tab 2 to serve the same purpose of supporting the tab 2.

[0037] In this embodiment, the direction perpendicular to the plane of the tab 2 is the third direction. In the third direction, the reinforcing part 3 protrudes from one side of the tab 2 and is recessed on the other side of the tab 2, so that the reinforcing part 3 can be pressed out on the tab 2 by a roller. The reinforcing part 3 is spaced from the side of the tab 2 in the second direction, so that the side of the tab 2 in the second direction will not be torn when the reinforcing part 3 is manufactured.

[0038] Combination Figure 3 and Figure 4 As shown, specifically, the reinforcing part 3 can be continuous or discontinuous in the first direction. When the reinforcing part 3 is discontinuous, the tab 2 is provided with a plurality of reinforcing sub-parts at intervals along the first direction, and the plurality of reinforcing sub-parts form the reinforcing part 3.

[0039] like Figure 5 As shown, this utility model also relates to a battery pack, including the battery. The battery includes a housing 100, a cover plate 200, and a battery cell 400. A receiving cavity is formed inside the housing 100. The cover plate 200 covers the housing 100 and seals the receiving cavity. A terminal post 300 is provided on the cover plate 200. The battery cell 400 is disposed within the receiving cavity. The tab 2 of the battery cell 400 is welded to the terminal post 300, forming a weld mark 600. Along the connection path between the tab 2 and the battery cell body 500, the distance between the weld mark 600 and the battery cell body 500 is L4mm, where 10mm ≤ L4 ≤ 50mm, and (L4 / H) > (h1 / H). Specifically, the value of L4 can be 15mm, 20mm, 30mm, or 40mm.

[0040] Because the heat generated during the welding of tab 2 and terminal post 300 will be transferred to the cell body 500, in order to avoid the heat affecting the active material layer and separator of the cell body 500 and causing a decrease in battery performance, the welding mark 600 between tab 2 and terminal post 300 needs to be kept away from the cell body 500. Furthermore, welding is performed at the location where the reinforcing part 3 is provided on tab 2, so that the contact area between two adjacent tabs 2 is larger, which is beneficial to improving welding efficiency and quality. Therefore, (L4 / H) > (h1 / H) to keep the welding mark 600 at a certain distance from the cell body 500 and to facilitate the welding work between two adjacent tabs 2.

[0041] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. A battery having two perpendicular directions: a first direction, a second direction, and a third direction, characterized in that, The device includes a housing, a cover plate, and a battery cell. The housing has a receiving cavity, and the cover plate covers the housing and seals the receiving cavity. The battery cell is disposed in the receiving cavity. The battery cell includes a battery cell body and an electrode tab. The battery cell body has an electrode plate, and the electrode tab extends outward from one side of the electrode plate. The direction in which the electrode tab extends is a first direction, and the direction along the plane of the electrode tab and perpendicular to the first direction is a second direction. The dimension of the electrode tab in the second direction is L1 mm, and the dimension of the battery cell body in the second direction is L2 mm, where L1 < L2. The electrode tab is provided with a reinforcing part. In the first direction, the minimum distance between the end of the reinforcing part near the electrode and the electrode is h1mm. The size of the electrode tab in the first direction is Hmm, where 0.002≤(L1 / L2)*(h1 / H)≤0.

07.

2. The battery according to claim 1, characterized in that, 20mm≤L1≤150mm, 50mm≤L2≤1000mm.

3. The battery according to claim 1, characterized in that, 0.02≤L1 / L2≤0.

4.

4. The battery according to claim 1, characterized in that, 3mm≤h1≤15mm, 10mm≤H≤50mm.

5. The battery according to claim 1, characterized in that, 0.06≤h1 / H≤0.

3.

6. The battery according to claim 1, characterized in that, 0.01≤(L1 / L2)*(h1 / H)≤0.

06.

7. The battery according to claim 1, characterized in that, In the first direction, the distance between the end of the reinforcing part away from the electrode and the end of the tab away from the electrode is h2mm, where 3mm≤h2≤15mm, 0.06≤h2 / H≤0.4, and 0.1≤L1 / L2≤0.

4.

8. The battery according to claim 1, characterized in that, The electrode tab transitions in an arc shape with the electrode plate on at least one side in the second direction, forming an arc-shaped portion.

9. The battery according to claim 8, characterized in that, The radius of the arc-shaped part is e mm, where 1 mm ≤ e ≤ 10 mm, and 0.002 ≤ (L1 / L2)*(h1 / H) ≤ 0.

06.

10. The battery according to claim 1, characterized in that, The direction perpendicular to the plane of the electrode tab is the third direction. In the third direction, the reinforcing part protrudes on one side of the electrode tab and is recessed on the other side of the electrode tab. The reinforcing part and the side of the electrode tab in the second direction are spaced apart.

11. A battery pack, characterized in that, Includes the battery as described in any one of claims 1 to 10.

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