Pole piece assembly and battery with same

Abstract

The utility model provides a pole piece assembly and a battery with the pole piece assembly. The pole piece assembly comprises a plurality of diaphragms which are stacked in sequence, the plurality of positive plates and the plurality of negative plates are respectively arranged between two adjacent diaphragms, the plurality of positive plates and the plurality of negative plates are arranged in a staggered manner along the thickness direction of the diaphragms, each positive plate is provided with a positive tab, each negative plate is provided with a negative tab, and the positive tabs and the negative tabs are arranged at the same ends of the positive plates and the negative plates; and in the thickness direction of the pole piece assembly, the orthographic projections of the two adjacent positive tabs on the positive pole piece are not overlapped, and the orthographic projections of the two adjacent negative tabs on the negative pole piece are not overlapped. According to the pole piece assembly disclosed by the utility model, when the plurality of pole pieces are laminated, the adjacent pole lugs can be staggered from each other, and the thickness of the plurality of pole pieces laminated is reduced, so that the welding difficulty of the pole lugs is reduced, the probability of pseudo soldering and improper welding is reduced, and the product yield of the pole piece assembly is improved.

Description

Technical Field

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

[0002] At present, in order to increase the battery capacity, the number of laminated layers in the battery is usually increased. As the number of laminated battery layers increases, the tabs will become thicker and thicker, which will eventually increase the difficulty of welding the tabs, making it extremely easy to have cold welds or incomplete welding. Utility Model Content

[0003] The utility model provides a new technical solution for a pole piece assembly, which can at least solve the problem of poor pole ear welding effect in the prior art.

[0004] The utility model also provides a battery with the pole piece assembly.

[0005] According to the first aspect of the utility model, the electrode assembly comprises: a plurality of diaphragms stacked in sequence; a plurality of positive electrode sheets and negative electrode sheets, the positive electrode sheets or the negative electrode sheets are respectively arranged between two adjacent diaphragms, the plurality of positive electrode sheets and the plurality of negative electrode sheets are staggered along the thickness direction of the diaphragms, each of the positive electrode sheets is respectively provided with a positive electrode ear, each of the negative electrode sheets is respectively provided with a negative electrode ear, the positive electrode ear and the negative electrode ear are arranged at the same end of the positive electrode sheet and the negative electrode sheet; wherein, in the thickness direction of the electrode assembly, the orthographic projections of two adjacent positive electrode ears on the positive electrode sheet do not overlap, and the orthographic projections of two adjacent negative electrode ears on the negative electrode sheet do not overlap.

[0006] Optionally, the plurality of positive electrode sheets include a first positive electrode sheet and a second positive electrode sheet 22 arranged adjacent to each other, the first positive electrode sheet is provided with a first positive electrode ear, the second positive electrode sheet 22 is provided with a second positive electrode ear, the plurality of the first positive electrode ears constitute a first positive electrode ear group, the plurality of the second positive electrode ears constitute a second positive electrode ear group, and the orthographic projections of the first positive electrode ear group and the second positive electrode ear group on the positive electrode sheet do not overlap; the plurality of negative electrode sheets include a first negative electrode sheet and a second negative electrode sheet arranged adjacent to each other, the first negative electrode sheet is provided with a first negative electrode ear, the second negative electrode sheet is provided with a second negative electrode ear, the plurality of the first negative electrode ears constitute a first negative electrode ear group, the plurality of the second negative electrode ears constitute a second negative electrode ear group, and the orthographic projections of the first negative electrode ear group and the second negative electrode ear group on the negative electrode sheet do not overlap.

[0007] Optionally, the spacing distance between the orthographic projections of the first positive electrode tab and the second positive electrode tab on the positive electrode sheet is 0-5 mm, and the spacing distance between the orthographic projections of the first negative electrode tab and the second negative electrode tab on the negative electrode sheet is 0-5 mm.

[0008] Optionally, a spacing distance between the orthographic projections of the first positive electrode tab and the second positive electrode tab on the positive electrode sheet is 0, and a spacing distance between the orthographic projections of the first negative electrode tab and the second negative electrode tab on the negative electrode sheet is 0.

[0009] Optionally, a thickness ratio of the first positive electrode tab to the second positive electrode tab is 0.9-1.1, and a thickness ratio of the first negative electrode tab to the second negative electrode tab is 0.9-1.1.

[0010] Optionally, the first positive electrode tab has the same thickness as the second positive electrode tab, and the first negative electrode tab has the same thickness as the second negative electrode tab.

[0011] Optionally, the thickness of the positive electrode tab and the negative electrode tab are 4 μm-15 μm respectively.

[0012] Optionally, the positive electrode ear and the negative electrode ear are in a rectangular or trapezoidal shape, and the widths of the positive electrode ear and the negative electrode ear are 5 mm-30 mm respectively.

[0013] Optionally, the separator is stacked in 2-150 layers.

[0014] A battery according to an embodiment of the second aspect of the utility model includes a pole piece assembly according to the above embodiment.

[0015] According to the pole piece assembly of the utility model, by arranging the positive pole ear on the positive pole piece and the negative pole ear on the negative pole piece into a structure staggered in the thickness direction of the pole piece assembly, when multiple pole pieces are stacked, adjacent pole ears can be staggered with each other, thereby reducing the thickness of the stacked pole ears, thereby reducing the difficulty of welding the pole ears, reducing the probability of cold welding and inadequate welding, and improving the product yield of the pole piece assembly.

[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 is a three-dimensional diagram of a pole piece assembly according to an embodiment of the utility model;

[0019] Figure 2 is a side view of a pole piece assembly according to an embodiment of the utility model;

[0020] Figure 3 It is a schematic structural diagram of each pole piece of a pole piece assembly according to an embodiment of the utility model;

[0021] Figure 4a and 4b The figure is a comparison diagram of the lug thickness of a pole piece assembly according to an embodiment of the utility model and a conventional pole piece assembly.

[0022] Reference numerals:

[0023] Pole piece assembly 100;

[0024] Diaphragm 10;

[0025] Positive electrode sheet 20; first positive electrode sheet 21; first positive electrode ear 211; second positive electrode sheet 22; second positive electrode ear 221;

[0026] Negative electrode sheet 30 ; first negative electrode sheet 31 ; first negative electrode ear 311 ; second negative electrode sheet 32 ​​; second negative electrode ear 321 . DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] 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.

[0030] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0031] 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.

[0032] The pole piece assembly 100 according to the embodiment of the utility model is first described in detail below with reference to the accompanying drawings.

[0033] like Figure 1 , Figure 2 , Figure 3 , Figure 4a and Figure 4b As shown, the electrode assembly 100 according to the embodiment of the present invention includes: a plurality of separators 10 stacked in sequence, a plurality of positive electrode sheets 20 and a negative electrode sheet 30 .

[0034] Specifically, the positive electrode sheet or the negative electrode sheet is respectively arranged between two adjacent diaphragms 10, and a plurality of positive electrode sheets 20 and a plurality of negative electrode sheets 30 are staggered along the thickness direction of the diaphragm 10. A positive electrode ear is respectively provided on each positive electrode sheet 20, and a negative electrode ear is respectively provided on each negative electrode sheet 30. The positive electrode ear and the negative electrode ear are arranged at the same end of the positive electrode sheet 20 and the negative electrode sheet 30; wherein, in the thickness direction of the electrode assembly 100, the orthographic projections of two adjacent positive electrode ears on the positive electrode sheet 20 do not overlap, and the orthographic projections of two adjacent negative electrode ears 30 on the negative electrode sheet do not overlap.

[0035] In other words, the electrode assembly 100 according to the embodiment of the utility model is mainly composed of a diaphragm 10, a positive electrode sheet 20 and a negative electrode sheet 30, wherein the diaphragm 10 is arranged as a multi-layer structure, a positive electrode sheet 20 or a negative electrode sheet 30 is arranged between any two adjacent diaphragms 10, and multiple positive electrode sheets 20 and multiple negative electrode sheets 30 are arranged alternately between the diaphragms 10, that is, two adjacent diaphragms 10 are taken as a unit, a positive electrode sheet 20 is arranged between the diaphragms 10 of one unit, and a negative electrode sheet 30 is arranged between the diaphragms 10 of adjacent units, and multiple diaphragm 10 units are arranged in sequence according to this rule and stacked to form a electrode assembly 100.

[0036] Each positive electrode sheet 20 and each negative electrode sheet 30 is provided with a pole ear, that is, the positive electrode sheet 20 is provided with a positive pole ear, and the negative electrode sheet 30 is provided with a negative pole ear. The positive pole ears on the plurality of positive electrode sheets 20 and the negative pole ears on the plurality of negative electrode sheets 20 are arranged at the same end of the electrode sheet assembly 100, that is, the positive pole ears and the negative pole ears extend toward the same side of the electrode sheet assembly 100. Among them, the positions of the positive pole ears on the plurality of positive electrode sheets 20 are different, and the positions of the negative pole ears on the plurality of negative electrode sheets 30 may also be different, so that when the plurality of positive electrode sheets 20 or the negative electrode sheets 30 are stacked, the positive pole ears of two adjacent positive electrode sheets 20 can be staggered and stacked, and the negative pole ears of two adjacent negative electrode sheets 30 can also be staggered and stacked, so that the thickness of the stacked plurality of pole ears can be effectively reduced, and the overall thickness of the pole ears can be reduced.

[0037] Therefore, according to the pole piece assembly 100 of the utility model, by arranging the positive pole ear on the positive pole piece 20 and the negative pole ear on the negative pole piece 30 into a structure staggered in the thickness direction of the pole piece assembly 100, when multiple pole pieces are stacked, adjacent pole ears can be staggered with each other, thereby reducing the thickness of the stacked multiple pole ears, thereby reducing the difficulty of welding the pole ears, reducing the probability of cold welding and incomplete welding, and improving the product yield of the pole piece assembly 100.

[0038] According to one embodiment of the utility model, a plurality of positive electrode sheets 20 include a first positive electrode sheet 21 and a second positive electrode sheet 22 arranged adjacent to each other, a first positive electrode ear 211 is provided on the first positive electrode sheet 21, a second positive electrode ear 221 is provided on the second positive electrode sheet 22, a plurality of first positive electrode ears 211 constitute a first positive electrode ear group, a plurality of second positive electrode ears 221 constitute a second positive electrode ear group, and the orthographic projections of the first positive electrode ear group and the second positive electrode ear group on the positive electrode sheet 20 do not overlap.

[0039] Correspondingly, the multiple negative electrode sheets 30 include a first negative electrode sheet 31 and a second negative electrode sheet 32 ​​arranged adjacent to each other, the first negative electrode sheet 31 is provided with a first negative electrode ear 311, the second negative electrode sheet 32 ​​is provided with a second negative electrode ear 321, the multiple first negative electrode ears 311 constitute a first negative electrode ear group, the multiple second negative electrode ears 321 constitute a second negative electrode ear group, and the positive projections of the first negative electrode ear group and the second negative electrode ear group on the negative electrode sheet 30 do not overlap.

[0040] Specifically, Figure 1 and Figure 2 As shown, in the present embodiment, the positive electrode sheet 20 is composed of a first positive electrode sheet 21 and a second positive electrode sheet 22, and the first positive electrode sheet 21 and the second positive electrode sheet 22 are alternately arranged in sequence on the diaphragm 10 unit, and the first positive electrode sheet 21 and the second positive electrode sheet 22 are respectively provided with corresponding electrode ears, that is, the first positive electrode sheet 21 is provided with a first positive electrode ear 211, and the second positive electrode sheet 22 is provided with a second positive electrode ear 221, and a plurality of first positive electrode ears 211 arranged at intervals together constitute a first positive electrode ear group, and a plurality of second positive electrode ears 221 arranged at intervals together constitute a second positive electrode ear group, and the orthographic projections of the entire first positive electrode ear group and the entire second positive electrode ear group on the positive electrode sheet 20 do not overlap with each other.

[0041] That is to say, the electrode assembly 100 includes a plurality of first positive electrode sheets 21 and a second positive electrode sheet 22, and the first positive electrode sheet 21 and the second positive electrode sheet 22 are not just the electrodes on the two adjacent sheets staggered from each other in the thickness direction of the electrode assembly 100, but the electrodes of the first positive electrode ear group composed of the first positive electrode ears 211 on the plurality of first positive electrode sheets 21 and the electrodes of the second positive electrode ear group composed of the second positive electrode ears 221 on the plurality of second positive electrode sheets 22 are staggered from each other, that is, Figure 3 As shown, the structures of the multiple first positive electrode sheets 21 are the same, and the structures of the multiple second positive electrode sheets 22 are also the same. The first positive electrode ear 211 can be arranged on the first positive electrode sheet 21 of the odd-numbered layers, and the second positive electrode ear 221 can be arranged on the second positive electrode sheet 22 of the even-numbered layers. This not only facilitates the preparation of the first positive electrode sheet 21 and the second positive electrode sheet 22, but also facilitates the assembly of the multiple positive electrode sheets 20.

[0042] The negative electrode sheet 30 includes a plurality of first negative electrode sheets 31 and second negative electrode sheets 32 disposed adjacent to each other. The structure of the negative electrode sheet 30 is similar to that of the positive electrode sheet 20 , and thus will not be described in detail.

[0043] In some specific embodiments of the present invention, the spacing distance between the orthographic projections of the first positive electrode tab 211 and the second positive electrode tab 221 on the positive electrode sheet is 0-5 mm, and the spacing distance between the orthographic projections of the first negative electrode tab 311 and the second negative electrode tab 321 on the negative electrode sheet is 0-5 mm.

[0044] Optionally, the spacing distance between the orthographic projections of the first positive electrode tab 211 and the second positive electrode tab 221 on the positive electrode sheet is 0, and the spacing distance between the orthographic projections of the first negative electrode tab 311 and the second negative electrode tab 321 on the negative electrode sheet is 0.

[0045] In other words, according to the embodiment of the utility model, the first positive electrode ear 211 and the second positive electrode ear 221 on the positive electrode sheet 20 are staggered in the thickness direction of the electrode assembly 100, and the distance between the two is 0-5mm, preferably 0, that is, although the first positive electrode ear 211 and the second positive electrode ear 221 are staggered in the thickness direction, when the two are stacked, one side edge of the first positive electrode ear 211 and one side edge of the second positive electrode ear 221 can fit each other, and the orthographic projections on the positive electrode sheet 20 can be connected to each other. Correspondingly, the ear structure of the negative electrode sheet 30 can also be arranged in the same way.

[0046] Therefore, according to the embodiment of the utility model, the tabs of the positive electrode sheet 20 and the negative electrode sheet 30 can be staggered with each other while reducing the occupied space, which not only improves the assembly convenience and product yield of the electrode assembly 100, but also improves the utilization rate of the battery.

[0047] According to some embodiments of the present invention, the thickness ratio of the first positive electrode tab 211 to the second positive electrode tab 221 is 0.9-1.1, and the thickness ratio of the first negative electrode tab 311 to the second negative electrode tab 321 is 0.9-1.1.

[0048] Optionally, the thickness of the first positive electrode tab 211 is equal to that of the second positive electrode tab 221 , and the thickness of the first negative electrode tab 311 is equal to that of the second negative electrode tab 321 .

[0049] That is to say, the thickness ratio of the first positive electrode ear 211 and the second positive electrode ear 221 of the positive electrode sheet 20 can be controlled between 0.9-1.1, preferably they can be equal to each other, and the thickness ratio of the first negative electrode ear 311 and the second negative electrode ear 321 of the negative electrode sheet 30 can also be controlled between 0.9-1.1, preferably they can be equal to each other.

[0050] Therefore, by controlling the thickness ratio of each pole ear, the overall thickness of the pole ear after the pole piece assembly 100 is stacked can be further controlled, thereby reducing the possibility of cold solder joints.

[0051] In some optional embodiments of the present invention, the thickness of the positive electrode tab and the negative electrode tab are 4 μm-15 μm respectively.

[0052] Optionally, the positive electrode ear and the negative electrode ear are in a rectangular or trapezoidal shape, and the widths of the positive electrode ear and the negative electrode ear are 5 mm to 30 mm, respectively.

[0053] In other words, the material, shape, thickness, etc. of the positive and negative tabs can be reasonably adjusted according to the actual use needs of the battery cell. The tab material can be aluminum foil or copper foil, and the positive and negative tabs can be trapezoidal or rectangular in shape. Therefore, the pole piece of this structure is easy to prepare and has strong versatility.

[0054] According to an embodiment of the present invention, the separator 10 is stacked with 2-150 layers. A positive electrode sheet 20 or a negative electrode sheet 30 is respectively arranged between two adjacent separators 10, and the specific structure of the positive electrode sheet 20 and the negative electrode sheet 30 can be the above structure. As shown in FIG. 4, Figure 4a To improve the front ear structure, Figure 4b In order to improve the rear tab structure, it can be clearly seen from FIG. 4 that the tab thickness can be effectively reduced by stacking the positive and negative tabs 20 and 30 of the tab assembly 100 .

[0055] The battery according to the embodiment of the utility model includes the pole piece assembly 100 according to the above embodiment. Since the pole piece assembly 100 according to the above embodiment of the utility model has the above technical effects, the pole piece assembly 100 according to the embodiment of the utility model also has the corresponding technical effects, that is, convenient welding, less cold welding and high product yield.

[0056] 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 assembly, characterized in that: include: A plurality of diaphragms stacked one on top of the other; A plurality of positive electrode sheets and negative electrode sheets, wherein the positive electrode sheet or the negative electrode sheet is respectively arranged between two adjacent separators, and the plurality of positive electrode sheets and the plurality of negative electrode sheets are staggered along the thickness direction of the separator, each of the positive electrode sheets is respectively provided with a positive electrode ear, and each of the negative electrode sheets is respectively provided with a negative electrode ear, and the positive electrode ear and the negative electrode ear are arranged at the same end of the positive electrode sheet and the negative electrode sheet; Wherein, in the thickness direction of the electrode assembly, the orthographic projections of two adjacent positive electrode tabs on the positive electrode sheet do not overlap, and the orthographic projections of two adjacent negative electrode tabs on the negative electrode sheet do not overlap.

2. The pole piece assembly according to claim 1, characterized in that: The plurality of positive electrode sheets include a first positive electrode sheet and a second positive electrode sheet arranged adjacent to each other, the first positive electrode sheet is provided with a first positive electrode ear, the second positive electrode sheet is provided with a second positive electrode ear, the plurality of the first positive electrode ears constitute a first positive electrode ear group, the plurality of the second positive electrode ears constitute a second positive electrode ear group, and the orthographic projections of the first positive electrode ear group and the second positive electrode ear group on the positive electrode sheet do not overlap; The multiple negative electrode sheets include a first negative electrode sheet and a second negative electrode sheet arranged adjacent to each other, the first negative electrode sheet is provided with a first negative electrode ear, the second negative electrode sheet is provided with a second negative electrode ear, the multiple first negative electrode ears constitute a first negative electrode ear group, the multiple second negative electrode ears constitute a second negative electrode ear group, and the positive projections of the first negative electrode ear group and the second negative electrode ear group on the negative electrode sheet do not overlap.

3. The pole piece assembly according to claim 2, characterized in that: The spacing distance of the orthographic projections of the first positive electrode tab and the second positive electrode tab on the positive electrode sheet is 0-5 mm, and the spacing distance of the orthographic projections of the first negative electrode tab and the second negative electrode tab on the negative electrode sheet is 0-5 mm.

4. The pole piece assembly according to claim 2, characterized in that: The spacing distance of the orthographic projections of the first positive electrode tab and the second positive electrode tab on the positive electrode sheet is 0, and the spacing distance of the orthographic projections of the first negative electrode tab and the second negative electrode tab on the negative electrode sheet is 0.

5. The pole piece assembly according to claim 2, characterized in that: The thickness ratio of the first positive electrode tab to the second positive electrode tab is 0.9-1.1, and the thickness ratio of the first negative electrode tab to the second negative electrode tab is 0.9-1.

1.

6. The pole piece assembly according to claim 2, characterized in that: The first positive electrode tab has the same thickness as the second positive electrode tab, and the first negative electrode tab has the same thickness as the second negative electrode tab.

7. The pole piece assembly according to claim 1, characterized in that: The thickness of the positive electrode tab and the negative electrode tab are 4 μm-15 μm respectively.

8. The pole piece assembly according to claim 1, characterized in that: The positive electrode ear and the negative electrode ear are in a rectangular or trapezoidal shape, and the widths of the positive electrode ear and the negative electrode ear are 5 mm to 30 mm, respectively.

9. The pole piece assembly according to claim 1, characterized in that: The separator is stacked in 2 to 150 layers.

10. A battery, characterized in that: A pole piece assembly comprising any one of claims 1-9.

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