Cathode collector plate of cylindrical battery, cathode cover plate of cylindrical battery and cylindrical battery

Abstract

The utility model discloses a cylindrical battery cathode collector plate, a cylindrical battery cathode cover plate and a cylindrical battery. The cylindrical battery negative current collector plate comprises a negative current collector plate body, a negative current collector plate groove is formed in the side surface, away from a battery cell, of the negative current collector plate body, and one end of the negative current collector plate groove is connected with a bendable negative current collector plate connecting part; and the cathode collector plate connecting part is used for connecting the cylindrical battery cathode cover plate with the cylindrical battery cathode collector plate. According to the utility model, the negative collector plate is conveniently connected with the negative cover plate, the matched negative collector plate groove is arranged, so that the negative collector plate connecting part is conveniently accommodated and matched with the negative cover plate on the outer side of the negative collector plate, and the negative collector plate connecting part is conveniently welded with the negative cover plate side.

Description

Technical Field

[0001] The utility model relates to the technical field of cylindrical batteries, in particular to a negative electrode current collector for a cylindrical battery, a negative electrode cover for a cylindrical battery and a cylindrical battery. Background Art

[0002] A battery is a cup, trough, or other container or part of a composite container that contains an electrolyte solution and metal electrodes to generate an electric current. It is a device that can convert chemical energy into electrical energy. A battery generally includes a shell and a winding core located inside the shell. During the battery manufacturing process, the electrolyte needs to be injected into the shell so that the electrolyte fills the inside of the winding core. For batteries with injection holes, the injection holes need to be sealed after the electrolyte is injected.

[0003] Cylindrical batteries include a cylindrical shell and a pole core. The connecting piece leading out of the pole core is generally bent in a Z shape before being led out, which will increase the internal space of the battery, resulting in low utilization of the internal space of the battery, which is not conducive to improving the battery capacity and energy density. In addition, the Z-shaped bend requires a special mechanism to be implemented during the assembly process, which increases the process cost and affects the processing progress. At the same time, during use, the pole core expands and contracts inside the shell, and the Z-shaped bend of the connecting piece is pulled, which may cause the risk of overcurrent failure of the key electrical connection. In addition, the existing cylindrical battery negative collector and cover plate welding is a penetration weld, which penetrates the cover plate to connect the negative collector, which is a thick-thin weld, and is often prone to poor welding, such as cold welding and welding through. Utility Model Content

[0004] The utility model aims to overcome the deficiencies and defects of the prior art and to provide a cylindrical battery negative electrode current collector, a cylindrical battery negative electrode cover plate and a cylindrical battery.

[0005] The first aspect of the utility model provides a negative electrode current collector disk, comprising a negative electrode current collector disk body, wherein the negative electrode current collector disk body is provided with a negative electrode current collector disk groove on the side surface facing away from the battery cell, and one end of the negative electrode current collector disk groove is connected to a bendable negative electrode current collector disk connecting portion, and the negative electrode current collector disk connecting portion is used to connect the negative electrode cover plate of a cylindrical battery with the negative electrode current collector disk of the cylindrical battery.

[0006] The negative electrode current collector plate groove is a linear through groove, the center of the negative electrode current collector plate body is located in the negative electrode current collector plate groove, and the two ends of the negative electrode current collector plate groove are connected to the circumference of the negative electrode current collector plate body.

[0007] The negative electrode current collector body is provided with negative electrode current collector through holes as channels for electrolyte infiltration.

[0008] Wherein, the negative electrode current collecting disc through hole is located in the negative electrode current collecting disc groove.

[0009] The second aspect of the utility model provides a negative electrode cover plate for a cylindrical battery, comprising a negative electrode cover plate body, wherein the negative electrode cover plate body is used in conjunction with the cylindrical battery collector plate described in the first aspect of the utility model, and a negative electrode cover plate groove is provided on the surface of the negative electrode cover plate body facing the battery cell side, which cooperates with the negative electrode collector plate groove to form an accommodating cavity to accommodate the bent negative electrode collector plate connecting portion.

[0010] The negative electrode cover groove is a linear structure groove whose two ends terminate at predetermined positions inside the surface of the negative electrode cover.

[0011] Wherein, both ends of the negative electrode cover groove are connected to the surface of the negative electrode cover where it is located through a transition portion.

[0012] Wherein, an explosion-proof valve is formed on the negative electrode cover body by notching, and the explosion-proof valve and the negative electrode cover groove are respectively arranged on the upper and lower surfaces of the negative electrode cover body.

[0013] Wherein, the notch of the explosion-proof valve is C-shaped.

[0014] The third aspect of the present invention provides a cylindrical battery, comprising the cylindrical battery negative electrode collector plate according to the first aspect of the present invention and the cylindrical battery negative electrode cover plate according to the second aspect of the present invention.

[0015] The setting of the negative current collector disc connection part for cylindrical batteries of the present application facilitates the connection between the negative current collector disc and the negative electrode cover plate, and a matching negative current collector disc groove is provided to facilitate the accommodation of the negative current collector disc connection part and the matching of the negative electrode cover plate on the outside of the negative current collector disc, and facilitate welding from the negative current collector disc connection part to the negative electrode cover plate side.

[0016] The negative electrode cover groove of the negative electrode cover for cylindrical batteries of the present application is arranged opposite to the negative electrode collector plate groove, and a groove accommodating cavity is formed between the negative electrode collector plate groove and the negative electrode cover groove. The negative electrode collector plate connecting portion can be accommodated in the groove accommodating cavity after being bent, so that the internal space of the cylindrical battery will not be increased, which is beneficial to improving the energy density of the cylindrical battery; when the battery falls or rolls, the bent connecting portion can also play a buffering role.

[0017] In addition, the negative electrode current collector connection portion of the cylindrical battery of the present application is located in the groove accommodating cavity, which can achieve a positioning effect without deviation. Compared with the existing penetration welding method of the negative electrode cover plate and the negative electrode current collector, which is prone to problems such as cold welding and over-welding leading to welding penetration, this connection method makes battery welding easier and greatly reduces the risk of poor welding and battery scrapping. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the axonometric structure of the negative electrode current collecting disk of the utility model.

[0019] Figure 2 It is a schematic diagram of the axonometric structure of the negative electrode cover plate of the utility model.

[0020] Figure 3 It is a cross-sectional schematic diagram of the negative electrode cover plate of the present utility model.

[0021] Figure 4 It is a first assembly schematic diagram of the negative electrode current collecting plate, the negative electrode cover plate and the battery terminal of the utility model.

[0022] Figure 5 This is a second assembly schematic diagram of the negative electrode current collecting plate, the negative electrode cover plate and the battery terminal of the utility model.

[0023] Figure 6 The utility model is a cross-sectional view of a cylindrical battery formed by a negative electrode current collecting disk and a negative electrode cover plate.

[0024] Figure 7 for Figure 6 A partial enlarged view of the negative electrode side of the cylindrical battery.

[0025] Figure 8 for Figure 6 A partial enlarged image of the positive electrode side of the cylindrical battery. DETAILED DESCRIPTION

[0026] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] like Figure 1 As shown, in the first aspect of an embodiment of the utility model, there is provided a negative electrode current collector disk, including a negative electrode current collector disk body 10, wherein a negative electrode current collector disk groove 11 is provided on the side surface of the negative electrode current collector disk body facing away from the battery cell, and one end of the negative electrode current collector disk groove is connected to a bendable negative electrode current collector disk connecting portion 12, and the negative electrode current collector disk connecting portion is used to connect the negative electrode cover plate of a cylindrical battery with the negative electrode current collector disk of a cylindrical battery.

[0028] In one embodiment, the negative electrode current collector disc groove 11 is a linear structure through groove, which is located at the axial edge of the negative electrode current collector disc groove. The center of the negative electrode current collector disc body 10 is located in the negative electrode current collector disc groove 11, and is connected to the circumferential surface of the negative electrode current collector disc body at both ends of the negative electrode current collector disc groove 11.

[0029] Preferably, the thickness of the negative collector disc body 10 is 0.2-0.8 mm, and the depth of the negative collector disc groove 11 is 20%-60% of the body thickness. More preferably, the thickness of the negative collector disc body 10 is 0.5 mm, and the depth of the negative collector disc groove 11 is 40% of the body thickness, that is, the depth of the negative collector disc groove is 0.2 mm.

[0030] In one embodiment, the negative electrode current collecting plate connecting portion 12 has a width of 0.4-1.5 mm and a thickness of 0.3-1.0 mm. If it is too narrow or too thin, it is easy to break and has a small flow area. If it is too wide or too thick, it will affect the welding quality, occupy the internal space, and reduce the energy density of the battery.

[0031] In addition, the battery pole ear at the negative electrode current collecting disc connection portion may also be arranged in a bent portion, a Z-shape, etc., so that the negative electrode current collecting disc connection portion plays a buffering role during welding.

[0032] In the above-mentioned embodiment, the negative electrode current collecting disc connecting portion 12 connects the negative electrode cover plate and the negative electrode current collecting disc 10 together by welding, gluing, clamping, etc.

[0033] The negative electrode current collecting disc 10 body is provided with a negative electrode current collecting disc through hole 13 as a channel for electrolyte infiltration. The diameter of the through hole is the same as the diameter of the injection hole, which can be 0.5 mm-4 mm, preferably 2.0 mm.

[0034] The negative electrode current collecting disc through hole 13 is located in the negative electrode current collecting disc groove.

[0035] The setting of the negative current collector disc connection part for cylindrical batteries of the present application facilitates the connection between the negative current collector disc and the negative electrode cover plate, and a matching negative current collector disc groove is provided to facilitate the accommodation of the negative current collector disc connection part and the matching of the negative electrode cover plate on the outside of the negative current collector disc, and facilitate welding from the negative current collector disc connection part to the negative electrode cover plate side.

[0036] like Figure 2 , Figure 3 As shown, the second aspect of the embodiment of the utility model provides a negative electrode cover plate for a cylindrical battery, including a negative electrode cover plate body 20, the negative electrode cover plate body is used in conjunction with the cylindrical battery collector plate 10 of the first aspect of the embodiment of the utility model, and the surface of the negative electrode cover plate body facing the battery cell side is provided with a negative electrode cover plate groove 22, which cooperates with the negative electrode collector plate groove 11 to form an accommodating cavity to accommodate the bent negative electrode collector plate connecting portion 12. When assembling the cylindrical battery, the negative electrode cover plate cover is arranged at the opening position of the cylindrical battery shell, and the sealing is completed by peripheral welding.

[0037] The negative electrode cover groove 22 is a linear structure groove whose two ends terminate at predetermined positions on the inner side of the surface of the negative electrode cover, that is, a through groove, so as to achieve surface contact between the negative electrode cover and the battery shell at the end to ensure the sealing performance of the battery.

[0038] Preferably, the thickness of the negative electrode cover body 20 is 0.4-1.2 mm, and the depth of the negative electrode cover groove 22 is 20%-60% of the thickness of the negative electrode cover body. More preferably, the thickness of the negative electrode cover body is 0.8 mm, and the depth of the negative electrode cover groove is 50% of the body thickness, that is, the depth of the negative electrode cover groove is 0.4 mm.

[0039] In a preferred embodiment, both ends of the negative electrode cover groove 22 are connected to the surface of the negative electrode cover where it is located through a transition portion. More preferably, the transition portion is an inclined portion. Figure 3 shown.

[0040] The negative electrode cover groove of the negative electrode cover for cylindrical batteries of the present application is arranged opposite to the negative electrode collector plate groove, and a groove accommodating cavity is formed between the negative electrode collector plate groove and the negative electrode cover groove. The negative electrode collector plate connecting portion can be accommodated in the groove accommodating cavity after being bent, so that the internal space of the cylindrical battery will not be increased, which is beneficial to improving the energy density of the cylindrical battery; when the battery falls or rolls, the bent connecting portion can also play a buffering role.

[0041] In addition, the negative electrode current collector connection portion of the cylindrical battery of the present application is located in the groove accommodating cavity, which can achieve a positioning effect without deviation. Compared with the existing penetration welding method of the negative electrode cover plate and the negative electrode current collector, which is prone to problems such as cold welding and over-welding leading to welding penetration, this connection method makes battery welding easier and greatly reduces the risk of poor welding and battery scrapping.

[0042] In one embodiment, an explosion-proof valve 21 is formed on the negative electrode cover body by a notched groove, and the explosion-proof valve 21 and the negative electrode cover groove 22 are respectively arranged on the upper and lower surfaces of the negative electrode cover body 20 and are arranged in the opposite direction to the negative electrode cover groove 22 .

[0043] Among them, the notch of the explosion-proof valve 21 is C-shaped. Preferably, the depth of the explosion-proof valve is 0.1-0.8mm, which accounts for about 10%-50% of the thickness of the negative electrode cover plate body. More preferably, the depth of the explosion-proof valve is 0.3mm, and the remaining thickness of the negative electrode cover plate body at the position of the negative electrode cover plate groove is 0.1mm. When the battery is short-circuited or gas is produced to generate a large air pressure, the strength at the explosion-proof valve is the lowest, and exhaust is preferentially discharged from the explosion-proof valve to prevent the battery from exploding, thereby improving safety performance.

[0044] See also Figure 5 , Figure 6 As shown, the third aspect of the embodiment of the utility model provides a cylindrical battery, including the cylindrical battery negative electrode collector plate described in the first aspect of the embodiment of the utility model and the cylindrical battery negative electrode cover plate described in the second aspect of the embodiment of the utility model.

[0045] See also Figure 6 , Figure 7 as well as Figure 8 As shown, the cylindrical battery provided by the third aspect of the embodiment of the utility model comprises a battery cell 50 formed by winding a positive electrode sheet, a separator and a negative electrode sheet, the positive / negative electrode ears of the battery cell are respectively connected to the positive / negative current collecting disk and then put into the shell, the positive electrode ear 80 of the battery is connected to the positive current collecting disk 90 on the positive electrode column side, the positive current collecting disk is connected to the positive electrode column 40, and the positive electrode column and the positive electrode column are connected by penetration welding through the positive electrode column side, and the positive electrode column and the positive electrode column are penetrated and connected, and there is a liquid injection hole 41 on the positive electrode column to inject electrolyte, the positive electrode column 40 and the shell 30 as the negative electrode are riveted structures, and are separated by an insulating glue 70; the negative electrode current collecting disk is connected to the negative electrode cover plate through the negative electrode current collecting disk connecting part, the negative electrode current collecting disk is welded to the negative electrode ear 60, after the negative electrode current collecting disk and the negative electrode cover plate are connected, the peripheral welding of the negative electrode cover plate and the shell 30 is finally performed, and finally the assembly is formed.

[0046] In the process of connecting the negative electrode collector plate and the negative electrode cover plate, the negative electrode cover plate groove 22 can be found by CCD positioning, and then the negative electrode collector plate connecting portion 12 is placed in the negative electrode cover plate groove 22 for laser welding. Then, the negative electrode collector plate connecting portion 12 is bent, and it can be bent once (such as Figure 5 as shown) or 2 times (as shown Figure 6 After the negative collector plate connecting portion 12 is bent, the negative collector plate connecting portion 12 is accommodated in the groove accommodating cavity formed by the alignment of the negative collector plate groove 11 and the negative electrode groove 22 of the cover plate, so as not to occupy the internal space of the battery.

[0047] In the cylindrical battery of the present application, the connection portion of the negative current collector disc is located in the groove accommodating cavity between the negative current collector disc and the negative cover plate, which will not increase the internal space of the battery and is beneficial to improving the energy density of the battery; in addition, the connection portion of the negative current collector disc is located in the groove accommodating cavity, which can achieve a positioning effect without deviation.

[0048] The setting of the negative current collector disc connection part for cylindrical batteries of the present application facilitates the connection between the negative current collector disc and the negative electrode cover plate, and a matching negative current collector disc groove is provided to facilitate the accommodation of the negative current collector disc connection part and the matching of the negative electrode cover plate on the outside of the negative current collector disc, and facilitate welding from the negative current collector disc connection part to the negative electrode cover plate side.

[0049] The negative electrode cover groove of the negative electrode cover for cylindrical batteries of the present application is arranged opposite to the negative electrode collector plate groove, and a groove accommodating cavity is formed between the negative electrode collector plate groove and the negative electrode cover groove. The negative electrode collector plate connecting portion can be accommodated in the groove accommodating cavity after being bent, so that the internal space of the cylindrical battery will not be increased, which is beneficial to improving the energy density of the cylindrical battery; when the battery falls or rolls, the bent connecting portion can also play a buffering role.

[0050] In cylindrical batteries, the penetration welding method of the negative electrode cover and the negative electrode collector plate is from the outside to the inside, and the thick welding is thin, which is prone to problems such as cold welding and over-welding leading to welding penetration. The design of the structure of the present application adopts the connection method of the negative electrode collector plate connection part, which makes battery welding easier, greatly reduces the risk of poor welding and battery scrapping, and minimizes the problem of cold welding and over-welding leading to welding penetration.

[0051] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. For those skilled in the art, it is obvious that the utility model is not limited to the details of the above exemplary embodiments, and the utility model can be implemented in other specific forms without departing from the spirit or basic features of the utility model.

[0052] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0053] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A negative electrode current collector for a cylindrical battery, comprising a negative electrode current collector body, characterized in that: The negative collector plate body is provided with a negative collector plate groove on the side surface facing away from the battery cell, one end of the negative collector plate groove is connected to a bendable negative collector plate connecting portion, and the negative collector plate connecting portion is used to connect the negative cover plate of the cylindrical battery with the negative collector plate of the cylindrical battery.

2. The negative electrode current collector of a cylindrical battery according to claim 1, characterized in that: The negative electrode current collecting disc groove is a linear structure through groove, the center of the negative electrode current collecting disc body is located in the negative electrode current collecting disc groove, and the two ends of the negative electrode current collecting disc groove are connected to the circumference of the negative electrode current collecting disc body.

3. The negative electrode current collector of a cylindrical battery according to claim 1, characterized in that: The negative electrode current collecting disc body is provided with negative electrode current collecting disc through holes, which serve as channels for electrolyte infiltration.

4. The negative electrode current collector of a cylindrical battery according to claim 1, characterized in that: The negative electrode current collecting plate through hole is located in the negative electrode current collecting plate groove.

5. A negative electrode cover plate for a cylindrical battery, comprising a negative electrode cover plate body, characterized in that: The negative electrode cover body is used in conjunction with the cylindrical battery collector disc according to any one of claims 1 to 4. The surface of the negative electrode cover body facing the battery cell is provided with a negative electrode cover groove, which cooperates with the negative electrode collector disc groove to form an accommodating cavity to accommodate the bent negative electrode collector disc connecting portion.

6. The negative electrode cover plate of a cylindrical battery according to claim 5, characterized in that: The negative electrode cover plate groove is a linear structure groove whose two ends terminate at predetermined positions inside the surface of the negative electrode cover plate.

7. The negative electrode cover plate of a cylindrical battery according to claim 6, characterized in that: Both ends of the negative electrode cover groove are connected to the surface of the negative electrode cover where it is located through transition parts.

8. The negative electrode cover plate of a cylindrical battery according to claim 5, characterized in that: An explosion-proof valve is formed on the negative electrode cover plate body by notching, and the explosion-proof valve and the negative electrode cover plate groove are respectively arranged on the upper and lower surfaces of the negative electrode cover plate body.

9. The negative electrode cover plate of a cylindrical battery according to claim 8, characterized in that: The notch of the explosion-proof valve is C-shaped.

10. A cylindrical battery, characterized in that: It comprises the negative electrode current collector of the cylindrical battery according to any one of claims 1 to 4 and the negative electrode cover of the cylindrical battery according to any one of claims 5 to 9.

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