Pole piece and battery with same

Abstract

The utility model provides a pole piece and a battery with the same, the pole piece comprises a main body part and an extension part, the main body part is provided with a coating area and an empty foil area, the coating area is coated with an electrode material, and the empty foil area is positioned at at least one end of the coating area; the extension parts are arranged at at least one end of the main body part, the extension parts are connected with the corresponding empty foil areas, and the thickness of each extension part is smaller than that of the main body part. According to the pole piece disclosed by the utility model, the main body part coated with the electrode material is separated from the extension part for the pole lug, so that the phenomenon of belt breakage of the pole piece caused by inconsistent tension of the coating area and the empty foil area in the rolling process of the pole piece is avoided, and meanwhile, the thickness of the extension part is smaller than that of the main body part, so that the occupied space of the pole lug can be effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and more specifically, to a pole piece and a battery comprising the pole piece. Background Art

[0002] With the development of technology, the application scope of batteries is becoming more and more extensive. They are widely used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, as well as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, aerospace and other fields.

[0003] At present, when producing battery pole pieces, due to the large number of layers of laminated battery cell pole ears, high welding difficulty, and large space occupation, the battery cell capacity will be reduced. If the pole ears are lengthened, they can only be rolled in a single width, which leads to low production efficiency. In addition, during the rolling process of the pole pieces, the coating area will inevitably extend, while the empty foil area will not extend because it is not subjected to rolling. As a result, the tension between the coating area and the empty foil area is inconsistent, which makes it easy to break the belt. In particular, when the coating area and the empty foil area are too wide, rolling is more likely to cause belt breakage. Utility Model Content

[0004] The utility model provides a new technical solution for a pole piece, which can at least solve one problem in the prior art.

[0005] The utility model provides a pole piece, comprising: a main body, on which a coating area and a hollow foil area are arranged, the coating area is coated with electrode material, and the hollow foil area is located at at least one end of the coating area; an extension part, which is arranged at at least one end of the main body, and is connected to the corresponding hollow foil area, wherein the thickness of each extension part is respectively less than the thickness of the main body.

[0006] Optionally, at least a portion of the empty foil area is formed as a first welding portion, the extended portion is provided with a second welding portion corresponding to the first welding portion, and the first welding portion is welded to the second welding portion.

[0007] Optionally, the first welding portion covers the empty foil area.

[0008] Optionally, empty foil areas are respectively provided at both ends of the coating area, and extension parts are respectively provided at both ends of the main body.

[0009] Optionally, the main body is formed as a rectangular sheet, and the empty foil area is formed as a long strip sheet extending along the width direction of the main body.

[0010] Optionally, the width of each of the empty foil areas is 4 mm to 8 mm.

[0011] Optionally, the width of the extension portion is 10 mm to 50 mm.

[0012] Optionally, the main body and the extension are aluminum foils respectively, the thickness of the main body is 10 μm to 13 μm, and the thickness of the extension is 6 μm to 8 μm.

[0013] Optionally, the main body and the extension are copper foils respectively, the thickness of the main body is 6 μm to 10 μm, and the thickness of the extension is 4 μm to 6 μm.

[0014] According to a second aspect of the utility model, a battery is provided, comprising the pole piece described in the above embodiment.

[0015] According to the pole piece of the utility model, by separately arranging the main body coated with the electrode material and the extension part used to form the pole ear, and assembling the two when necessary, it can effectively avoid the phenomenon of pole piece breaking caused by inconsistent tension between the coating area and the empty foil area during the rolling process; in addition, setting the thickness of the extension part to be smaller than the thickness of the main body can effectively reduce the space occupied by the pole ear, thereby improving the space layout inside the battery cell.

[0016] Other features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention.

[0018] Figure 1 It is a plan view of a pole piece according to an embodiment of the utility model;

[0019] Figure 2 It is a plan view of the main body according to an embodiment of the utility model;

[0020] Figure 3 It is a side view of a pole ear according to an embodiment of the utility model;

[0021] Figure 4 It is a plan view of a pole piece after cutting according to an embodiment of the utility model;

[0022] Figure 5 It is a plan view of a main body portion after cutting according to an embodiment of the utility model;

[0023] Figure 6 It is a side view of a pole ear after cutting according to an embodiment of the utility model.

[0024] Reference numerals:

[0025] Pole piece 100;

[0026] Main body 10; coating area 11; empty foil area 12; first welding part 13;

[0027] Extension portion 20; second welding portion 21. DETAILED DESCRIPTION

[0028] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention.

[0029] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present invention, its application, or uses.

[0030] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0031] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0032] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0033] The pole piece 100 according to the embodiment of the utility model is described in detail below with reference to the accompanying drawings.

[0034] like Figures 1 to 6 As shown, the pole piece 100 according to the embodiment of the present invention includes a main body portion 10 and an extension portion 20 .

[0035] Specifically, a coating area 11 and an empty foil area 12 are provided on the main body 10, the coating area 11 is coated with an electrode material, and the empty foil area 12 is located at at least one end of the coating area 11; the extension part 20 is provided at at least one end of the main body 10, and the extension part 20 is connected to the corresponding empty foil area 12, wherein the thickness of each extension part 20 is respectively smaller than the thickness of the main body 10.

[0036] In other words, the pole piece 100 according to the embodiment of the utility model mainly includes a main body 10 and an extension portion 20, wherein the main body 10 is provided with a coating area 11 and a hollow foil area 12, the coating area 11 is the main part of the pole piece, and the coating area 11 is coated with electrode material. The type of electrode material can be reasonably selected according to the use scenario of the pole piece 100, and this application does not make any special limitation.

[0037] like Figure 2 and Figure 5 As shown, the empty foil area 12 can be located at least at one end of the coating area 11, that is, Figure 5 As shown, the empty foil area 12 can be located at one end of the coating area 11; Figure 2 As shown, the empty foil area 12 can also be located at both ends of the coating area 11. The extension part 20 is provided at at least one end of the main body 10, and the extension part 20 is connected to the corresponding empty foil area 12, that is, the number of the extension parts 20 corresponds to the number of the empty foil areas 12. When the empty foil area 12 is located at one end of the coating area 11, the extension part 20 is connected to the empty foil area 12; when the empty foil area 12 is located at both ends of the coating area 11, there are also two extension parts 20, which are connected to the two empty foil areas 12 respectively.

[0038] It should be noted that in the prior art, the pole piece is usually only composed of a main body, on which a coating area and a blank area without coating are formed. The blank area will be formed into a pole ear later, which is an important connection channel for the pole piece to form a secondary battery. Due to the functional requirements of the blank area, the blank area needs to have a large area. During the rolling process of the pole piece with this structure, the coating area and the blank area are prone to inconsistent tension due to the rolling extension, which leads to the phenomenon of broken belts in the pole piece.

[0039] In comparison, according to the pole piece 100 of the embodiment of the utility model, by designing the blank area in the traditional sense as an independent extension portion 20, the coating area 11 of the main body 10 can cover a larger area on the main body 10, and the empty foil area 12 only needs to reserve a very small area to ensure the connection effect with the extension portion 20, which can effectively reduce the problem of uneven tension between the empty foil area 12 and the coating area 11 when the main body 10 is rolled; and the thickness of each extension portion 20 is respectively less than the thickness of the main body 10, and the thickness of the pole ear of the prepared pole piece 100 is effectively reduced, thereby effectively reducing the space occupied by the pole ear in the battery.

[0040] Therefore, according to the pole piece of the embodiment of the utility model, by separately arranging the main body 10 coated with the electrode material and the extension part 20 used to form the pole ear, and assembling the two when necessary, it is possible to effectively avoid the pole piece 100 from breaking due to inconsistent tension between the coating area 11 and the empty foil area 12 during the rolling process; in addition, setting the thickness of the extension part 20 to be smaller than the thickness of the main body 10 can effectively reduce the space occupied by the pole ear, thereby improving the space layout inside the battery cell.

[0041] According to an embodiment of the present invention, at least a portion of the empty foil area 12 is formed as a first welding portion 13 , the extended portion 20 is provided with a second welding portion 21 corresponding to the first welding portion 13 , and the first welding portion 13 is welded to the second welding portion 21 .

[0042] In some optional embodiments, the first weld 13 covers the empty foil area.

[0043] In other words, unlike the coating area 11 coated with electrode material, the empty foil area 12 is a blank area, and the empty foil area 12 can be used for welding with the extension portion 20. A part of the empty foil area 12 can be formed as the first welding portion 13, and the empty foil area 12 can also be formed as the first welding portion 13 as a whole. The position on the extension portion 20 corresponding to the first welding portion 13 is formed as the second welding portion 21, and the second welding portion 21 and the first welding portion 13 can be welded by roll welding.

[0044] Among them, the main body 10 of the pole piece serves as a current collector metal material, has a large porosity and a good heat dissipation mechanism, is beneficial to the heat dissipation of the battery, and improves the cycle performance and safety performance of the battery. The extension portion 20 is rolled to form a thin current collector. When the extension portion 20 is connected to the empty foil area 12, the first welding portion 13 and the second welding portion 21 are close to form a welding area, and a roll welding connection is performed along the gap between the first welding portion 13 and the second welding portion 21. The roll welding can be continuous roll welding or intermittent roll welding. The width of the welding is generally 3mm to 6mm, and does not exceed the range of the first welding portion 13 and the second welding portion 21. Through the roll welding connection, the main body 10 of the current collector and the extension portion 20 of the thin current collector are combined together, and the current can be better concentrated on the pole ear, thereby improving the current transmission efficiency.

[0045] In some optional embodiments, empty foil areas 12 are respectively provided at both ends of the coating area 11 , and extension parts 20 are respectively provided at both ends of the main body 10 .

[0046] In other words, during the manufacturing process, Figure 1 , Figure 2 As shown, empty foil areas 12 are provided at both ends of the coating area 11, and the empty foil areas 12 at both ends are roll welded to the extension part 10. Then, the electrode is cut from the middle to form two electrode pieces. Of course, it can also be as shown in FIG. Figure 4 , Figure 5 As shown, a hollow foil area 12 is provided at one end of the coating area 11, and the hollow foil area 12 is roll-welded to the extension portion 10. In the actual manufacturing process, the specific solution can be determined based on comprehensive considerations such as the size, thickness, quantity and cost of the electrode piece.

[0047] In some other embodiments of the present invention, the main body 10 is formed as a rectangular sheet, and the empty foil area 12 is formed as a long strip extending along the width direction of the main body 10 .

[0048] In other words, if Figures 1 to 6As shown, the shape of the pole piece 100 is generally a rectangular sheet, and accordingly, the shapes of the main body 10 and the extension 20 are also formed in rectangular shapes, and the empty foil area 12 is arranged at least at one end of the main body 10 in the length direction. The shape of the empty foil area 12 is also rectangular, and the empty foil area 12 uses the edge of the main body 10 in the width direction as the long side and a part of the edge of the main body 10 in the length direction as the wide side. Therefore, the main body 10 of this structure is not only suitable for most batteries at present, but also easy to prepare.

[0049] In some optional embodiments, the width of each empty foil area 12 is 4 mm to 8 mm, and the width of the extension portion 20 is 10 mm to 50 mm.

[0050] It should be noted that in the prior art, in order to facilitate rolling, the empty foil area often needs to be wider, usually 30mm to 40mm. During rolling, it is more likely to cause uneven tension due to rolling extension and breakage of the foil. In addition, since the width of the empty foil area is relatively large, it is not convenient to roll multiple pieces.

[0051] According to the pole piece 100 of the embodiment of the utility model, the extension portion 20 is provided to serve as the pole ear, so that the width of the empty foil area 12 can be greatly reduced. The width of the empty foil area 12 can be 4 mm to 8 mm. For example, the width of the empty foil area 12 can be any value among 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm or a range value between any two of them. The width dimension of the empty foil area 12 can be measured by a vernier caliper.

[0052] Therefore, by greatly reducing the width of the empty foil area 12, it is not only convenient for subsequent multiple rolling of the main body 10 and the extension 20 to reduce the phenomenon of pole piece breakage, but also reducing the width of the empty foil area 12 can reduce the material cost of the pole piece.

[0053] The width of the extension portion 20 can be reasonably set according to different battery cell models and types, and is usually 10mm to 50mm. For example, the width of the extension portion 20 can be any value of 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm or a range between any two values. The width of the extension portion 20 can be measured by a vernier caliper.

[0054] In some optional embodiments, the main body 10 and the extension 20 are aluminum foils respectively, the thickness of the main body 10 is 10 μm to 13 μm, and the thickness of the extension 20 is 6 μm to 8 μm.

[0055] In some other optional embodiments, the main body 10 and the extension 20 are copper foils respectively, the thickness of the main body 10 is 6 μm to 10 μm, and the thickness of the extension 20 is 4 μm to 6 μm.

[0056] In other words, the overall structure of the pole piece 100 can adopt a conventional metal foil, and the thickness of the metal foil is 5μm to 100μm. The specific thickness can be further selected according to different material properties. The metal foil can be at least one of nickel foil, aluminum foil, copper foil, and silver foil.

[0057] like Figure 3 , Figure 6 As shown, when the main body 10 and the extension 20 are respectively aluminum foils, the thickness of the main body 10 is 10μm to 13μm, for example, the thickness of the main body can be any one of 10μm, 10.5μm, 11μm, 11.5μm, 12μm, 12.5μm, 13μm or a range between any two of them, and the thickness of the extension 20 is 6μm to 8μm, for example, the thickness of the extension 20 can be any one of 6μm, 6.5μm, 7μm, 7.5μm, 8μm or a range between any two of them.

[0058] like Figure 3 , Figure 6 As shown, when the main body 10 and the extension 20 are copper foils respectively, the thickness of the main body 10 is 6μm to 10μm, for example, the thickness of the main body can be any one of 6μm, 6.5μm, 7μm, 7.5μm, 8μm, 8.5μm, 9μm, 9.5μm, 10μm or a range between any two of them, and the thickness of the extension 20 is 4μm to 6μm, for example, the thickness of the extension 20 can be any one of 4μm, 4.5μm, 5μm, 5.5μm, 6μm or a range between any two of them.

[0059] Therefore, through different selections of pole pieces, according to their material properties, the appropriate thickness of the main body 10 and the extension 20 are selected, so that the material properties can be matched with the pole piece size and manufacturing cost to achieve the optimal solution, while satisfying the mechanical strength and conductivity of the pole piece 100, thereby ensuring the performance of the battery. At the same time, it can be clearly seen that the thickness of the pole ear formed after the pole piece 100 is die-cut is significantly thinner, which effectively reduces the occupied space.

[0060] The battery according to the embodiment of the utility model includes the pole piece 100 according to the above embodiment. Since the pole piece 100 according to the above embodiment of the utility model has the above technical effects, the battery according to the embodiment of the utility model also has corresponding technical effects, that is, the pole piece is not prone to broken bands, the pole ears are easy to weld, the occupied space is reduced, and the battery cell capacity is improved.

[0061] Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A pole piece, characterized in that: include: A main body (10), wherein the main body (10) is provided with a coating area (11) and a hollow foil area (12), the coating area (11) is coated with an electrode material, and the hollow foil area (12) is located at at least one end of the coating area (11); An extension portion (20), the extension portion (20) being arranged at at least one end of the main body portion (10), the extension portion (20) being connected to the corresponding empty foil area (12), wherein the thickness of each extension portion (20) is respectively smaller than the thickness of the main body portion (10).

2. The pole piece according to claim 1, characterized in that: At least a portion of the empty foil area (12) is formed as a first welding portion (13), the extended portion (20) is provided with a second welding portion (21) corresponding to the first welding portion (13), and the first welding portion (13) is welded to the second welding portion (21).

3. The pole piece according to claim 2, characterized in that: The first welding portion (13) covers the empty foil area (12).

4. The pole piece according to claim 1, characterized in that: The empty foil areas (12) are respectively provided at both ends of the coating area (11), and the extension parts (20) are respectively provided at both ends of the main body (10).

5. The pole piece according to claim 1, characterized in that: The main body (10) is formed as a rectangular sheet, and the empty foil area (12) is formed as a long strip sheet extending along the width direction of the main body (10).

6. The pole piece according to claim 5, characterized in that: The width of each of the empty foil areas (12) is 4 mm to 8 mm.

7. The pole piece according to claim 6, characterized in that: The width of the extension portion (20) is 10 mm to 50 mm.

8. The pole piece according to claim 1, characterized in that: The main body (10) and the extension (20) are respectively made of aluminum foil, the thickness of the main body (10) is 10 μm to 13 μm, and the thickness of the extension (20) is 6 μm to 8 μm.

9. The pole piece according to claim 1, characterized in that: The main body (10) and the extension (20) are respectively made of copper foil, the main body (10) has a thickness of 6 μm to 10 μm, and the extension (20) has a thickness of 4 μm to 6 μm.

10. A battery, characterized in that: A pole piece (100) comprising any one of claims 1 to 9.

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