Pole piece, battery and electric equipment

Abstract

The utility model discloses a pole piece, battery and electric equipment, the pole piece comprises a pole piece main body and a pole lug connected with the pole piece main body, the pole lug comprises a first area and a second area, one side of the second area is connected with the pole piece main body, the other side of the second area is connected with the first area, and the first area is connected with the pole piece main body. And the thickness of the first region is greater than that of the second region. According to the pole piece, the battery and the electric equipment provided by the utility model, the different areas of the pole piece have different thicknesses, and the thickness of the first area which is far away from the pole piece main body and is used for welding is greater than that of the second area which is close to the pole piece main body, so that the diversion area of the pole piece is increased, and the current-carrying capacity of the pole piece is improved; the poor heat dissipation capability of the tabs during charging and discharging of the battery is avoided, so that the performance of the battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a pole piece, a battery and an electrical device. Background Art

[0002] In recent years, batteries have been widely used in smart phones, tablet computers, smart wearables, power tools, electric vehicles, etc. With the widespread use of batteries, consumers have put forward higher requirements for battery performance, service life and safety.

[0003] Tabs are important components of lithium-ion polymer battery products. Batteries are divided into positive and negative electrodes. Tabs are metal conductors that lead the positive and negative electrodes out of the battery core. Generally speaking, the tabs of the positive and negative electrodes of the battery are the contact points during charging and discharging. However, the existing tabs will heat up during battery charging and discharging, and the current conduction capacity needs to be improved. Utility Model Content

[0004] A series of simplified concepts are introduced in the utility model content section, which will be further described in detail in the detailed implementation section. The utility model content section of the utility model does not mean to attempt to define the key features and essential technical features of the technical solution claimed for protection, nor does it mean to attempt to determine the scope of protection of the technical solution claimed for protection.

[0005] The utility model provides a pole piece, comprising a pole piece body and a pole ear connected to the pole piece body, the pole ear comprising a first area and a second area, one side of the second area is connected to the pole piece body, the other side of the second area is connected to the first area, and the thickness of the first area is greater than the thickness of the second area.

[0006] Exemplarily, the overlapping area formed by the folded pole ears defines the first area, the second area is a non-overlapping area located between the overlapping area and the pole piece body, and the thickness of the overlapping area is greater than the thickness of the non-overlapping area.

[0007] Exemplarily, the thickness of the first region is twice the thickness of the second region.

[0008] Exemplarily, the tab is made of a single layer of metal material, the folded single layer of metal material defines the first region, the first region includes at least two layers of metal material, and the second region includes a single layer of metal material.

[0009] Exemplarily, the pole ear includes a first end away from the pole piece body and a second end connected to the pole piece body, and the first end is folded toward the second end to form the first region.

[0010] Exemplarily, the tab is folded along a folding line, and a distance between the folding line and the first end is smaller than a distance between the folding line and the second end.

[0011] Exemplarily, the electrode sheet includes a positive electrode sheet or a negative electrode sheet.

[0012] The utility model provides a battery, comprising a positive electrode sheet, a negative electrode sheet and a diaphragm, wherein the positive electrode sheets and the negative electrode sheets are arranged alternately, the diaphragm is arranged between adjacent positive electrode sheets and the negative electrode sheets, and the positive electrode sheet and / or the negative electrode sheet are the electrode sheets as described above.

[0013] Exemplarily, the battery further comprises: a lead-out sheet, wherein:

[0014] There are multiple positive electrode sheets, and the first regions of the multiple positive electrode sheets are welded and connected to form a positive electrode tab, and the positive electrode tab is welded to the lead-out sheet; and / or

[0015] There are multiple negative electrode sheets, and the first regions of the multiple negative electrode sheets are welded and connected to form a negative electrode ear, and the negative electrode ear is welded to the lead-out sheet.

[0016] Exemplarily, the welding comprises ultrasonic welding

[0017] The utility model provides an electrical device, comprising the battery and an electrical load as described above, wherein the battery provides electrical energy for the electrical load.

[0018] According to the pole piece, battery and electrical equipment provided by the utility model, different areas of the pole ear have different thicknesses, and the thickness of the first area used for welding away from the pole piece body is greater than the thickness of the second area close to the pole piece body, thereby increasing the conduction area of ​​the pole ear and improving the current carrying capacity of the pole ear, thereby avoiding poor heat dissipation at the pole ear during battery charging and discharging, thereby improving the performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following drawings of the present invention are used as a part of the present invention for understanding the present invention. The drawings show the embodiments of the present invention and their descriptions, and are used to explain the principle of the present invention.

[0020] In the attached figure:

[0021] Figure 1 is a schematic diagram of a pole piece according to an embodiment of the utility model;

[0022] Figure 2 is a schematic diagram of a folding line according to an embodiment of the utility model;

[0023] Figure 3 is a schematic diagram of a pole piece stack according to an embodiment of the utility model;

[0024] Figure 4 The figure is a schematic structural diagram of a battery according to an embodiment of the utility model.

[0025] Reference numerals

[0026] 10. Pole body 20. Pole ear

[0027] 21. First area 22. Second area

[0028] 30. Fold Line

[0029] 1. Positive electrode 2. Negative electrode

[0030] 3. Diaphragm 4. Positive electrode ear

[0031] 5. Negative electrode ear DETAILED DESCRIPTION

[0032] In the following description, a large number of specific details are given to provide a more thorough understanding of the utility model. However, it is obvious to those skilled in the art that the utility model can be implemented without one or more of these details. In other examples, in order to avoid confusion with the utility model, some technical features known in the art are not described.

[0033] In order to thoroughly understand the present invention, a detailed description will be provided in the following description to illustrate a pole piece, a battery and an electrical device of the present invention. Obviously, the implementation of the present invention is not limited to the specific details familiar to technicians in the field of battery technology. The preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention can also have other embodiments.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the utility model. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of the features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0035] Now, exemplary embodiments according to the present utility model will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in a variety of different forms and should not be interpreted as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of the present utility model thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art. In the accompanying drawings, for the sake of clarity, the thickness of layers and regions is exaggerated, and the same reference numerals are used to represent the same elements, and thus their description will be omitted.

[0036] Aiming at the problem that the existing pole ear generates heat when the battery is charged and discharged, the utility model provides a pole piece, such as Figure 1 and Figure 3 As shown, it includes a pole piece body 10 and a pole ear 20 connected to the pole piece body 10, the pole ear 20 includes a first area 21 and a second area 22, one side of the second area 22 is connected to the pole piece body 10, and the other side of the second area 22 is connected to the first area 21, and the thickness of the first area 21 is greater than the thickness of the second area 22.

[0037] Exemplarily, the electrode sheet includes a positive electrode sheet or a negative electrode sheet; the electrode sheet body 10 includes a current collector and an active material on the surface of the current collector; the electrode tab 20 is composed of a single layer of metal material, and the single layer of metal material includes aluminum foil or copper foil.

[0038] In one embodiment, the electrode sheet is a positive electrode sheet. Taking a lithium-ion battery as an example, the electrode sheet body 10 of the positive electrode sheet of a lithium-ion battery is usually mixed evenly with a positive electrode active material (such as lithium cobalt oxide, lithium manganese oxide, lithium iron phosphate, etc.) and a conductive agent (such as acetylene black, conductive graphite, furnace black, etc.) and a binder (such as polyvinylidene fluoride, sodium carboxymethyl cellulose and styrene-butadiene rubber), stirred into a paste slurry, and evenly coated on both sides of the positive electrode collector (for example, aluminum foil), dried under a nitrogen flow to remove the organic dispersant, and then pressed into shape with a roller press, and then cut into a specified size according to design requirements. The tabs of the positive electrode sheet are led out from the positive electrode collector. The tabs of the positive electrode sheet are usually made of aluminum foil, and the thickness is usually 0.006mm to 0.016mm. The length and width can be designed as needed, and this application does not limit this.

[0039] In one embodiment, the electrode sheet is a negative electrode sheet. The negative electrode active material of the negative electrode sheet of the lithium-ion battery mainly includes graphite or lithium titanate, and the negative electrode current collector can be made of copper foil. The preparation process of the negative electrode sheet is roughly the same as that of the positive electrode sheet, which will not be repeated here. The tab of the negative electrode sheet is led out from the negative electrode current collector. The tab of the negative electrode sheet is usually made of copper foil, and its thickness is usually 0.004mm to 0.01mm. Its length and width can be designed as needed, and this application does not limit this.

[0040] Exemplarily, the overlapping area formed by the folded pole ears defines the first area 21, the second area 22 is a non-overlapping area located between the overlapping area and the pole piece body 10, and the thickness of the overlapping area is greater than the thickness of the non-overlapping area.

[0041] Exemplarily, the pole tab 20 includes a first end away from the pole piece body 10 and a second end connected to the pole piece body 10, and the first end is folded toward the second end to form the first region 21. The pole tab 20 is folded along a folding line 30, and the distance between the folding line 30 and the first end is smaller than the distance between the folding line and the second end.

[0042] In one embodiment, the pole piece body 10 includes a square or rectangular shape, and a pole ear 20 is connected to one side of the pole piece body 10. The shape of the pole ear 20 is rectangular, square or trapezoidal. Figure 1 and Figure 2 As shown, the shape of the pole ear 20 is an isosceles trapezoid, the upper base of the isosceles trapezoid is the first end away from the pole piece body 10 (ie, the distal end), and the lower base of the isosceles trapezoid is the second end connected to the pole piece body 10 (ie, the proximal end). Figure 2 The folding line 30 is shown, and the folding line 30 is located between the upper base and the lower base of the isosceles trapezoid, and the folding line 30 is parallel or nearly parallel to the upper base and the lower base of the isosceles trapezoid. Usually, the distance from the folding line 30 to the first end is 1mm to 2mm smaller than the distance from the folding line to the second end, so that a spacing of 1mm to 2mm can be formed between the folded first region 21 and the pole piece body 10, that is, the width of the second region 22. Taking the example that the spacing between the first end and the second end of the pole tab 20 is 10mm, the spacing between the folding line 30 and the first end is 4mm to 4.5mm, and the spacing between the folding line 30 and the second end is 5.5mm to 6mm. The first end of the pole tab 20 is folded toward the second end along the folding line 30 to form a Figure 1 and Figure 3 In the structure shown, the overlapping area after folding is used as the first area 21, and the non-overlapping area between the first area 21 and the pole piece body 10 is used as the second area 22.

[0043] By folding the pole ear, the thickness of the far end of the pole ear is increased, the conduction area of ​​the pole ear is increased, the current carrying capacity of the pole ear is improved, the heat at the pole ear during battery charging and discharging is avoided, and the performance of the battery is improved.

[0044] It should be noted that the above-mentioned embodiment increases the thickness of the distal end of the pole ear by folding, but this is not restrictive. Methods that can increase the thickness of the first region 21, such as directly integrally molding a pole ear with a thicker distal end during the pole ear manufacturing process, and welding the pole ear material at the distal end of the pole ear, are all applicable to the present application.

[0045] In one embodiment, since the tab 20 is usually composed of a single-layer metal material, such as aluminum foil, copper foil, etc., after the tab 20 is folded once as described above, the first region 21 is a double-layer metal material, and the thickness of the first region 21 is twice the thickness of the second region 22. Still taking the above-mentioned spacing of 10 mm between the first end and the second end of the tab 20 as an example, if two folding lines are respectively set at 4 mm and 7 mm away from the second end of the tab, and the first end of the tab 20 is folded toward the second end along the two folding lines in sequence, the first region 21 is a three-layer metal material, and the thickness of the first region 21 is three times the thickness of the second region 22. If the double-layer metal material is folded once to form a double-layer metal material, the first region 21 formed is a four-layer metal material, and the thickness of the first region 21 is four times the thickness of the second region 22. It should be noted that the number of folding lines 30 and the number of layers of the first region 21 can be selected as needed, and the present application does not limit this.

[0046] The utility model also provides a battery, such as Figure 3 He Ru Figure 4 As shown, it includes a positive electrode sheet 1, a negative electrode sheet 2 and a separator 3, wherein the positive electrode sheet 1 and the negative electrode sheet 2 are alternately arranged, and the separator 3 is arranged between the positive electrode sheet 1 and the negative electrode sheet 2, and the positive electrode sheet 1 and / or the negative electrode sheet 2 are the electrode sheets as described above.

[0047] In one embodiment, the positive electrode sheet 1, the negative electrode sheet 2 and the separator 3 are wound or stacked in the manner of separator-negative electrode sheet-separator-positive electrode sheet-separator-... to form a Figure 3 The structure shown, wherein the positive electrode sheet 1 and / or the negative electrode sheet 2 has a first area 21 formed by folding, so that the thickness of the first area 21 used for welding is greater than the thickness of the second area 22 close to the electrode body 10, and the extension direction of the pole ear of the positive electrode sheet 1 is opposite to the extension direction of the pole ear of the negative electrode sheet 2. It should be noted that the above embodiments are only exemplary, and the present application does not limit the number of pole ears of each positive electrode sheet 1 and / or each negative electrode sheet 2. The extension directions of the pole ears of the positive electrode sheet 1 and the negative electrode sheet 2 can be the same or different. For example, the extension direction of the pole ear of the positive electrode sheet is parallel, intersecting (for example, perpendicular) or opposite to the extension direction of the pole ear of the negative electrode sheet. Therefore, the battery can have pole ears at one end or at both ends, and the present application does not limit this.

[0048] Exemplarily, the battery also includes: a lead-out plate, wherein there are multiple positive electrode plates, and the first regions of the multiple positive electrode plates are welded and connected to form a positive electrode lug, and the positive electrode lug is welded to the lead-out plate; and / or, there are multiple negative electrode plates, and the first regions of the multiple negative electrode plates are welded and connected to form a negative electrode lug, and the negative electrode lug is welded to the lead-out plate.

[0049] In one embodiment, Figure 4 As shown, both the positive electrode sheet 1 and the negative electrode sheet 2 use the above-mentioned electrode sheet, and the thickness of the first area used for welding is greater than the thickness of the second area close to the electrode sheet body. The first area of ​​each positive electrode sheet 1 is connected by ultrasonic welding to form a positive electrode ear 4 of the battery, and the first area of ​​each negative electrode sheet 2 is connected by ultrasonic welding to form a negative electrode ear 5 of the battery. The positive electrode ear 4 and the negative electrode ear 5 after welding are further ultrasonically welded to the lead-out sheet.

[0050] In one embodiment, the battery comprises a laminated battery or a wound battery, such as a die-cut tab wound structure battery.

[0051] In one embodiment, the battery comprises a soft package structure battery or a hard shell structure battery, such as an aluminum shell structure battery.

[0052] The utility model also provides an electrical device, which comprises the battery and an electrical load as described above, wherein the battery provides electrical energy for the electrical load.

[0053] According to the pole piece, battery and electrical equipment provided by the utility model, different areas of the pole ear have different thicknesses, and the thickness of the first area used for welding away from the pole piece body is greater than the thickness of the second area close to the pole piece body, thereby increasing the conduction area of ​​the pole ear and improving the current carrying capacity of the pole ear, thereby avoiding poor heat dissipation at the pole ear during battery charging and discharging, thereby improving the performance of the battery.

[0054] The utility model has been described through the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the utility model to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the utility model is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the utility model, and these variations and modifications all fall within the scope of protection claimed by the utility model. The protection scope of the utility model is defined by the attached claims and their equivalents.

Claims

1. A pole piece, characterized in that: It includes a pole piece body and a pole ear connected to the pole piece body, the pole ear includes a first area and a second area, one side of the second area is connected to the pole piece body, the other side of the second area is connected to the first area, and the thickness of the first area is greater than the thickness of the second area.

2. The pole piece according to claim 1, characterized in that: The overlapping area formed by the folded pole ears defines the first area, and the second area is a non-overlapping area located between the overlapping area and the pole piece body, and the thickness of the overlapping area is greater than the thickness of the non-overlapping area.

3. The pole piece according to claim 1, characterized in that: The thickness of the first region is twice the thickness of the second region.

4. The pole piece according to claim 1, characterized in that: The tab is made of a single layer of metal material. The folded single layer of metal material defines the first region, the first region includes at least two layers of metal material, and the second region includes a single layer of metal material.

5. The pole piece according to claim 1, characterized in that: The pole ear includes a first end away from the pole piece body and a second end connected to the pole piece body, and the first end is folded toward the second end to form the first region.

6. The pole piece according to claim 5, characterized in that: The tab is folded along a folding line, and a distance between the folding line and the first end is smaller than a distance between the folding line and the second end.

7. The pole piece according to claim 1, characterized in that: The electrode sheet includes a positive electrode sheet or a negative electrode sheet.

8. A battery, characterized in that: It comprises a positive electrode sheet, a negative electrode sheet and a separator, wherein the positive electrode sheets and the negative electrode sheets are arranged alternately, the separator is arranged between adjacent positive electrode sheets and negative electrode sheets, and the positive electrode sheet and / or the negative electrode sheet is the electrode sheet according to any one of claims 1 to 6.

9. The battery according to claim 8, characterized in that Also includes: Lead-out sheet, where There are multiple positive electrode sheets, and the first regions of the multiple positive electrode sheets are welded and connected to form a positive electrode tab, and the positive electrode tab is welded to the lead-out sheet; and / or There are multiple negative electrode sheets, and the first regions of the multiple negative electrode sheets are welded and connected to form a negative electrode ear, and the negative electrode ear is welded to the lead-out sheet.

10. The battery according to claim 9, characterized in that The welding includes ultrasonic welding.

11. An electrical device, characterized in that: The invention comprises the battery according to any one of claims 8 to 10 and an electrical load, wherein the battery provides electrical energy for the electrical load.

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