Pole piece, battery cell and electric device

Abstract

The utility model discloses a kind of pole piece, battery monomer and electric device, it belongs to battery technical field, pole piece includes current collector, active material layer, pole lug part and opening, current collector includes main body part and protruding part, along the width direction of main body part, protruding part is set to at least one side of main body part and is set out relative to main body part protruding;Along the thickness direction of current collector, active material layer is located at least one side surface of current collector, and located main body part and protruding part;Pole lug part is connected with protruding part;Opening is set to pole lug part, and it is through pole lug part along the thickness direction of pole lug part, opening has first end and second end, opening extends from first end to second end along preset route.Opening is set, so that pole piece hits over roller, reduces the probability of folding, even if pole piece folds, part of pole lug part is folded along opening, reduces the degree of influence of folding.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to an electrode, a battery cell, and an electrical device. Background Technology

[0002] Lithium-ion batteries are now widely used in various fields. During their manufacturing process, the tab forming step is essential; this involves cutting the electrode sheets to form positive and negative tabs for subsequent connection to the positive and negative terminals. During rolling and transport, the electrode sheets are prone to collisions with equipment components, causing the tabs to fold. As the energy density requirements of battery cells increase, the foil material becomes thinner. To meet the demands of fast charging, the tab height is increasing; the thinner the foil, the higher the tab, leading to more severe tab folding and reduced production efficiency. Utility Model Content

[0003] This invention provides an electrode sheet, a battery cell, and an electrical device to solve the technical problem of the electrode tabs being easily folded in the prior art.

[0004] Based on the above concept, the technical solution adopted by this utility model is as follows:

[0005] An electrode sheet, comprising:

[0006] A current collector includes a main body and a protrusion. Along the width direction of the main body, the protrusion is disposed on at least one side of the main body and protrudes relative to the main body.

[0007] An active material layer is disposed on at least one side surface of the current collector along the thickness direction of the current collector, and is located in the main body and the protrusion.

[0008] The electrode tab is connected to the protrusion.

[0009] An opening is provided in the tab portion and extends through the tab portion along the thickness direction. The opening has a first end and a second end, and the opening extends from the first end to the second end along a predetermined route.

[0010] Preferably, the tab portion has a first edge away from the protrusion, and the first end is located at the first edge.

[0011] Preferably, the preset route is perpendicular to the first edge.

[0012] Preferably, the tab portion has a second edge connected to the protrusion portion, and the second end is located at the second edge or the second end is spaced apart from the second edge.

[0013] Preferably, the tab portion has a first edge away from the protrusion, and the first end is spaced apart from the first edge.

[0014] Preferably, the preset route is perpendicular to or parallel to the first edge.

[0015] Preferably, at least a portion of the opening has a straight edge; and / or, at least a portion of the opening has an arc-shaped edge.

[0016] Preferably, the total area of ​​the tab is A1, and the total area of ​​the opening is A2, where A2 is 5%-15% of A1;

[0017] And / or, the opening is provided in multiple ways, and the multiple openings are spaced apart along the width direction of the electrode tab;

[0018] And / or, the opening is provided in multiple ways, and the multiple openings are spaced apart along the height direction of the tab.

[0019] A single battery cell, comprising:

[0020] case;

[0021] An electrode assembly is housed in the housing, the electrode assembly comprising a first electrode, a second electrode, and a diaphragm; the first electrode and / or the second electrode are electrodes as described above.

[0022] An electrical device comprising a battery cell as described above.

[0023] The beneficial effects of this utility model are:

[0024] The electrode sheet proposed in this utility model includes a current collector, an active material layer, an electrode tab, and an opening. The current collector includes a main body and a protrusion. Along the width direction of the main body, the protrusion is disposed on at least one side of the main body and protrudes relative to the main body. Along the thickness direction of the current collector, the active material layer is disposed on at least one side surface of the current collector and is located between the main body and the protrusion. The electrode tab is connected to the protrusion. The opening is disposed on the electrode tab and extends through the electrode tab along the thickness direction of the electrode tab. The opening has a first end and a second end, and the opening extends from the first end to the second end along a predetermined route. The opening reduces the probability of the electrode sheet flipping when it impacts the roller. Even if the electrode sheet flips, part of the electrode tab flips along the opening, and the flipping is controllable and directional, preventing the entire electrode sheet from flipping or flipping randomly, thus reducing the impact of flipping. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of an electrode sheet provided in Embodiment 1 of this utility model;

[0026] Figure 2This is a schematic diagram of another electrode provided in Embodiment 1 of this utility model;

[0027] Figure 3 This is a schematic diagram of another electrode sheet provided in Embodiment 1 of this utility model;

[0028] Figure 4 This is a schematic diagram of an electrode sheet provided in Embodiment 2 of this utility model;

[0029] Figure 5 This is a schematic diagram of another electrode sheet provided in Embodiment 2 of this utility model;

[0030] Figure 6 This is a schematic diagram of another electrode sheet provided in Embodiment 2 of this utility model;

[0031] Figure 7 This is a schematic diagram of an electrode sheet provided in Embodiment 3 of this utility model;

[0032] Figure 8 This is a schematic diagram of another electrode sheet provided in Embodiment 3 of this utility model;

[0033] Figure 9 This is a schematic diagram of a battery cell provided in Embodiment 4 of this utility model;

[0034] Figure 10 This is a schematic diagram of multiple electrode plates in a single battery cell provided in Embodiment 4 of this utility model;

[0035] Figure 11 This is a schematic diagram of the battery provided in Embodiment 4 of this utility model;

[0036] Figure 12 This is a schematic diagram of the electrical device provided in Embodiment 4 of this utility model.

[0037] In the picture:

[0038] 10. Current collector; 11. Main body; 12. Protrusion;

[0039] 20. Ear portion; 21. First edge; 22. Second edge;

[0040] 30. Opening; 31. First end; 32. Second end;

[0041] 100. Battery; 110. Battery housing; 120. Individual battery cell. Detailed Implementation

[0042] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0043] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0044] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0046] The existing technology has a technical problem that the tabs are easy to fold. It is generally believed that when the tabs move on the roller, the uneven force on the large surface of the tabs causes crescent-shaped creases at the bottom of the tabs. When the tabs are uneven, they will fold when they move on the roller.

[0047] Example 1

[0048] See Figure 1This application provides an electrode sheet, including a current collector 10, an electrode tab 20, an active material layer, and an opening 30. The current collector 10 includes a main body 11 and a protrusion 12. Along the width direction of the main body 11, the protrusion 12 is disposed on at least one side of the main body 11 and protrudes relative to the main body 11. Along the thickness direction of the current collector 10, the active material layer is disposed on at least one side surface of the current collector 10 and is located between the main body 11 and the protrusion 12. The electrode tab 20 is connected to the protrusion 12. The opening 30 is disposed on the electrode tab 20 and extends through the electrode tab 20 along the thickness direction of the electrode tab 20. The opening 30 has a first end 31 and a second end 32, and the opening 30 extends from the first end 31 to the second end 32 along a predetermined route. The opening 30 reduces the probability of electrode flipping when it impacts the roller. Even if the electrode flips, only a portion of the tab 20 flips along the opening 30. This flipping is controllable and directional, preventing the entire electrode from flipping or flipping randomly, thus reducing the impact of flipping. By setting the opening 30, tab flipping can be improved and its impact reduced without requiring significant structural modifications, minimizing the impact on tab processing and reducing production costs.

[0049] At least a portion of the surface of the current collector 10 is provided with an active material layer, while the tab portion 20 is not provided with an active material layer. Exemplarily, both the main body portion 11 and the protrusion portion 12 are provided with active material layers. Exemplarily, along the thickness direction of the current collector 10, the active material layer is provided on one side surface of the current collector 10. Exemplarily, along the thickness direction of the current collector 10, the active material layer is provided on both sides surface of the current collector 10. Extending the active material layer from the main body portion 11 to the protrusion portion 12 increases the stability of the tab portion 20 and further reduces the risk of the tab portion 20 folding over.

[0050] The shape of the main body 11 can be set according to actual needs, such as a rectangle. For example, a protrusion 12 is provided on one side of the main body 11 in the width direction. For example, a protrusion 12 is provided on both sides of the main body 11 in the width direction. Along the length direction of the main body 11, one protrusion 12 can be provided on the main body 11, or multiple protrusions 12 can be provided at intervals.

[0051] The shape of the tab 20 can be set according to actual needs, such as rectangular or trapezoidal. The height direction of the tab 20 is the direction away from the protrusion 12, and the width direction of the tab 20 is perpendicular to the height direction. In the figure, X represents the width direction of the tab 20, and Y represents the height direction of the tab 20. Figure 1 As shown, the width direction of the main body 11 is the Y direction, and the length direction of the main body 11 is the X direction.

[0052] The thickness direction of the current collector 10 is consistent with the thickness direction of the tab 20. It can be understood that the thickness direction of the tab 20 is perpendicular to both the width direction and the height direction of the tab 20.

[0053] In this embodiment, the width of the tab 20 is a1, and the height of the tab 20 is b1. Wherein, a1 is 30mm to 60mm; and / or, b1 is 20mm to 35mm; and / or, a1 / b1 is 1 to 2.5. Compared to existing tabs, the width of the tab 20 is increased, and the height of the tab 20 is reduced. While ensuring that the flow area remains essentially unchanged, this further reduces the risk of the tab 20 folding due to the impact of the drooping roller.

[0054] For example, the width a1 of the tab 20 is 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, or 60mm. For example, the height b1 of the tab 20 is 20mm, 22mm, 25mm, 28mm, 30mm, 32mm, or 35mm. For example, the ratio a1 / b1 of the width a1 of the tab 20 to the height b1 of the tab 20 is 1.3 to 2.2. For example, a1 / b1 is 1.5 to 2.

[0055] The total area of ​​the tab 20 is A1, and the total area of ​​the opening 30 is A2, where A2 is 5%-15% of A1. The total area of ​​the opening 30 should be as small as possible to prevent damage to the overall strength of the tab 20 or to avoid affecting its flow area. The total area A1 of the tab 20 is equal to the product of a1 and b1. For example, A2 is 5%-10% of A1. If A2 accounts for more than 15% of A1, the total area of ​​the tab 20 needs to be increased.

[0056] In some embodiments, the opening 30 is a cut. The cut is a narrow, elongated cut formed on the tab 20 by cutting the tab 20, which avoids reducing the area of ​​the tab 20 due to the opening 30, thus preventing the flow area of ​​the tab 20 from being affected. In some embodiments, the opening 30 is a notch formed by removing a portion of the tab 20. The notch can be formed by cutting and removing a portion of the tab 20, which prevents the tabs 20 on both sides of the notch from abutting or overlapping, thus avoiding affecting the stress release effect of the tab 20 at the notch.

[0057] The cutting method for cutting the tab portion 20 can be laser cutting, blade cutting, or other cutting methods, and is not limited here.

[0058] The number of openings 30 provided on each tab 20 can be adjusted according to actual needs. For example, each tab 20 has one opening 30, located at the midpoint of its width. Alternatively, each tab 20 may have multiple openings 30, spaced apart along its width. The openings 30 can be arranged at equal or non-equal intervals, without limitation. When two or more openings 30 are provided on the tab 20, the total area A2 of the openings 30 is the sum of the areas of all openings 30.

[0059] In some embodiments, the tab 20 has corners at both ends on the side away from the protrusion 12, and the opening 30 may be located between the two corners. The tab 20 has a first edge 21 away from the protrusion 12 and a second edge 22 connected to the protrusion 12. Exemplarily, the first edge 21 and the second edge 22 are parallel. Exemplarily, the tab 20 is rectangular, and the two corners are located at the ends of the first edge 21.

[0060] In this embodiment, the tab portion 20 has a first edge 21 away from the protrusion 12, and a first end 31 is located at the first edge 21. By setting the first end 31 at the first edge 21, the opening 30 divides the tab portion 20 into at least two parts, thereby releasing the stress caused by uneven force when a single large tab passes through the roller, thus preventing the tab from flipping.

[0061] The second end 32 is located on the side of the first end 31 near the protrusion 12. The preset route can be a straight line, a broken line, or a curve. Exemplarily, the preset route is a straight line, and the preset route is perpendicular to or at an angle to the first edge 21. In this embodiment, the preset route is perpendicular to the first edge 21, which facilitates processing and production. In other embodiments, the preset route is at an angle to the first edge 21, and the size of the angle can be set as needed.

[0062] For example, the tab 20 has a second edge 22 connected to the protrusion 12, and a second end 32 is located at the second edge 22 or spaced apart from the second edge 22. When the first end 31 is located at the first edge 21 and the second end 32 is located at the second edge 22, and the preset path is perpendicular to the first edge 21, the height of the opening 30 is equal to the height of the tab 20. When the first end 31 is located at the first edge 21 and the second end 32 is spaced apart from the second edge 22, and the preset path is perpendicular to the first edge 21, the height of the opening 30 is less than the height of the tab 20.

[0063] For example, the opening 30 extends along the height direction of the tab 20, and the height of the opening 30 is h, with the ratio of h to b1 being 0.1-1. For example, the ratio of h to b1 is 0.5-1. The larger the ratio of h to b1, the better the anti-folding effect, because after completely dividing a tab 20 into two or more parts, it is easier to reduce the force on the tab 20 as it passes through the roller.

[0064] For example, the width of the opening 30 along the width direction of the tab 20 is w, where w is 0.1mm to 5mm. For example, w is 0.1mm to 2mm. The smaller w is, the better, as it has less impact on the solder area. The width of the opening 30 along the direction from the first end 31 to the second end 32 can be uniform or non-uniform.

[0065] The shape of the opening 30 can be set according to actual needs. Exemplarily, at least a portion of the edge of the opening 30 extends in a straight line; and / or, at least a portion of the edge of the opening 30 extends in an arc shape. Exemplarily, such as... Figure 1 As shown, the edge of the opening 30 extends in a straight line, and the opening 30 is rectangular. For example, as... Figure 2 As shown, the edge of the opening 30 extends in a curved shape, and the opening 30 is semi-elliptical, reducing stress concentration. For example, as... Figure 3 As shown, the edge of the opening 30 extends in a straight line, and the opening 30 is trapezoidal. Along the direction from the first end 31 to the second end 32, the width of the opening 30 gradually decreases, which facilitates processing and production.

[0066] Example 2

[0067] Figures 4 to 6 Embodiment 2 is shown, wherein components that are the same as or corresponding to those in Embodiment 1 are referred to by the same reference numerals as those in Embodiment 1. For simplicity, only the differences between Embodiment 2 and Embodiment 1 are described. The difference is that the tab 20 has a first edge 21 away from the protrusion 12, and the first end 31 is spaced apart from the first edge 21.

[0068] For example, the first end 31 and the second end 32 are both located on the side of the first edge 21 near the protrusion 12. By setting the first end 31 at a distance from the first edge 21, and setting the first end 31 and the second end 32 on the side of the first edge 21 near the protrusion 12, the opening 30 forms a hollow structure on the tab 20, which has little impact on the strength of the tab 20.

[0069] The preset route can be a straight line, a broken line, or a curve. For example, the preset route is a straight line, and it is perpendicular to or at an angle to the first edge 21. In this embodiment, the preset route is perpendicular to the first edge 21, which facilitates processing and production. In other embodiments, the preset route is at an angle to the first edge 21, and the angle can be set as needed.

[0070] The shape of the opening 30 can be set according to actual needs, such as rectangular, elliptical or trapezoidal.

[0071] The number of openings 30 provided on each tab 20 can be adjusted according to actual needs. For example, each tab 20 has one opening 30, located at the midpoint of its width. For example, each tab 20 has multiple openings 30, spaced apart along its width, i.e., spaced apart along a direction parallel to the first edge 21. For example, each tab 20 has multiple openings 30, spaced apart along its height, i.e., spaced apart along a direction perpendicular to the first edge 21. For example, each tab 20 has multiple openings 30, spaced apart along both its width and height.

[0072] like Figure 4 and Figure 5 As shown, the opening 30 extends along the height direction of the tab 20, and the height of the opening 30 is h, with the ratio of h to b1 being 0.1-0.9. For example, the ratio of h to b1 is 0.5-0.9. The larger the ratio of h to b1, the better the anti-folding effect, because after completely dividing a tab 20 into two or more parts, it is easier to reduce the force on the tab 20 passing through the roller. In reality, due to certain objective reasons, it may not be necessary to cut to the bottom or through, but it can still have a good effect on reducing the force on the tab 20 passing through the roller.

[0073] like Figure 6 As shown, the opening 30 extends along the height direction of the tab 20, and at least two openings 30 are spaced apart along the height direction of the tab 20. The height of the opening 30 is h, and the ratio of h to b1 is 0.1-0.4. For example, the ratio of h to b1 is 0.3-0.4. The larger the ratio of h to b1, the better the anti-folding effect.

[0074] Example 3

[0075] Figure 7 and Figure 8 Embodiment 3 is shown, wherein components that are the same as or corresponding to those in Embodiment 2 are referred to using the same reference numerals as those in Embodiment 2. For simplicity, only the differences between Embodiment 3 and Embodiment 2 are described. The difference is that the preset route is parallel to the first edge 21. That is, the preset route extends along the width direction of the tab 20, and the first end 31 and the second end 32 are located at the same height in the height direction of the tab 20.

[0076] The number of openings 30 provided on each tab 20 can be adjusted according to actual needs. For example, each tab 20 is provided with one opening 30, located at the midpoint of the height direction of the tab 20. For example, each tab 20 is provided with multiple openings 30, spaced apart along the width direction of the tab 20, and / or spaced apart along the height direction of the tab 20.

[0077] Example 4

[0078] Figures 9 to 12 Example 4 is shown. This example provides a battery cell 120, which includes a housing and an electrode assembly. The electrode assembly is housed in the housing and includes a first electrode, a second electrode, and a separator. The first electrode and / or the second electrode are electrodes from any of the above embodiments.

[0079] In some embodiments, the battery cell 120 includes multiple layers of electrodes. When welding the electrodes (e.g., welding the tab 20 to the adapter plate, or welding the tab 20 directly to the terminal post), welding is typically performed with the tab 20 in a flat position. To ensure that all tabs 20 on the side furthest from the main body 11 are substantially flush, the uppermost tabs 20 are generally higher in height. Figure 10 As shown. The lower the height of the tab 20, the lower the probability of it folding. In this embodiment, for multiple electrodes in the battery cell 120, the tabs 20 whose height exceeds the set range are made of electrodes from any of the above embodiments, that is, the tabs 20 are provided with openings 30, and the other tabs 20 are made of conventional structures. This setting reduces the risk of tab folding, simplifies the process, and saves costs.

[0080] For example, the tab 20 whose height exceeds the set range is a tab 20 with a height greater than or equal to 20 mm. For multiple electrodes in the battery cell 120, the tabs 20 with a height greater than or equal to 20 mm are provided with openings 30, while the remaining tabs 20 adopt a conventional structure. For example, the tabs 20 with a height greater than or equal to 25 mm are provided with openings 30. For example, the tabs 20 with a height greater than or equal to 30 mm are provided with openings 30.

[0081] See Figure 11 This embodiment also provides a battery 100, including the aforementioned battery cell 120. Exemplarily, the battery 100 includes a battery housing 110 and a plurality of battery cells 120, the plurality of battery cells 120 being disposed within the battery housing 110. The battery housing 110 includes a first housing and a second housing that are interlocked, the first housing and the second housing forming a receiving cavity, within which the battery cells 120 are located. The battery 100 can be a module or a battery pack.

[0082] See Figure 12 This embodiment also provides an electrical device, including the aforementioned battery cell 120, or the aforementioned battery 100. The electrical device can be, but is not limited to, a mobile phone, tablet, laptop, electric toy, power tool, electric vehicle, electric car, ship, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0083] The above embodiments merely illustrate the basic principles and characteristics of this utility model. This utility model is not limited to the above embodiments. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. An electrode sheet, characterized in that, include: The current collector (10) includes a main body (11) and a protrusion (12). Along the width direction of the main body (11), the protrusion (12) is disposed on at least one side of the main body (11) and protrudes from the main body (11). An active material layer is disposed on at least one side surface of the current collector (10) along the thickness direction of the current collector (10) and located on the main body (11) and the protrusion (12). The electrode ear (20) is connected to the protrusion (12); An opening (30) is provided in the tab portion (20) and extends through the tab portion (20) along the thickness direction of the tab portion (20). The opening (30) has a first end (31) and a second end (32). The opening (30) extends from the first end (31) to the second end (32) along a preset route.

2. The electrode sheet according to claim 1, characterized in that, The tab portion (20) has a first edge (21) away from the protrusion (12), and the first end (31) is located at the first edge (21).

3. The electrode sheet according to claim 2, characterized in that, The preset route is perpendicular to the first edge (21).

4. The electrode sheet according to claim 2, characterized in that, The tab (20) has a second edge (22) connected to the protrusion (12), and the second end (32) is located at the second edge (22) or the second end (32) is spaced apart from the second edge (22).

5. The electrode sheet according to claim 1, characterized in that, The tab portion (20) has a first edge (21) away from the protrusion (12), and the first end (31) is spaced apart from the first edge (21).

6. The electrode sheet according to claim 5, characterized in that, The preset route is perpendicular or parallel to the first edge (21).

7. The electrode sheet according to claim 1, characterized in that, At least a portion of the edges of the opening (30) extend in a straight line; and / or, at least a portion of the edges of the opening (30) extend in an arc shape.

8. The electrode sheet according to any one of claims 1-7, characterized in that, The total area of ​​the tab (20) is A1, and the total area of ​​the opening (30) is A2, where A2 is 5%-15% of A1; And / or, the opening (30) is provided in multiple ways, and the multiple openings (30) are spaced apart along the width direction of the tab (20); And / or, the opening (30) is provided in multiple ways, and the multiple openings (30) are spaced apart along the height direction of the tab (20).

9. A single battery cell, characterized in that, include: case; An electrode assembly is housed in the housing, the electrode assembly comprising a first electrode, a second electrode, and a diaphragm; The first electrode and / or the second electrode are the electrodes described in any one of claims 1-8.

10. An electrical device, characterized in that, Includes the battery cell as described in claim 9.

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