A novel cylindrical battery structure and battery pack

Abstract

The utility model relates to battery structure technical field discloses a novel cylindrical battery structure and battery pack, and battery structure includes steel shell, and the steel shell is the hollow one end opening's cylinder structure, is equipped with the roll core in the steel shell, is equipped with the apron at the steel shell opening, and the roll core is connected through the negative electrode current collector disc between the steel shell bottom, and the positive electrode current collector disc extends the foldable connecting piece and is connected with the apron, and the edge of apron is equipped with the sealing ring between the steel shell, and the steel shell is equipped with the explosion -proof groove. The scheme connects the apron with the apron after the positive electrode current collector disc is folded through the connecting piece, and the positive electrode current collector disc and the connecting piece are the integral structure of disposable processing of same material quality, and compared with the integral structure that the connecting piece and the current collector disc of different material quality are welded before, the structure of the scheme is further simplified, and the explosion -proof groove is set up in the steel shell to cope with the high pressure explosion -proof inside the battery, and the complicated explosion -proof component is replaced, and the battery production cost is reduced.

Description

Technical Field

[0001] This utility model relates to the field of battery structure technology, and in particular to a novel cylindrical battery structure and battery pack. Background Technology

[0002] Lithium-ion batteries are a type of electrochemical energy storage device with lithium metal or lithium ions as the core. When a lithium-ion battery is charged, the externally applied voltage causes lithium ions in the positive electrode to be deintercalated and intercalated, pass through the electrolyte and the separator, and flow to and intercalate into the negative electrode. At the same time, in order to maintain electrical neutrality, electrons in the positive electrode also flow to the negative electrode through the external circuit. When discharging, lithium ions are deintercalated from the negative electrode, pass through the electrolyte and the separator, and flow to and intercalate into the positive electrode. Electrons in the negative electrode also flow to the positive electrode through the external circuit.

[0003] The applicant's earlier Chinese patent application CN2025204314514 discloses a battery structure and an electrical device. The battery structure includes a housing, a cap on the top of the housing, and a sealing ring between the cap and the housing. Inside the housing are a first current collector, a second current collector, and a battery cell. The top and bottom of the battery cell are respectively provided with the first current collector and the second current collector. The first current collector is located between the cap and the battery cell. A bent portion extends from the edge of the first current collector, and a connecting portion extends from the bent portion. The connecting portion is located between the cap and the first current collector through the bent portion, and the connecting portion is connected to the inner side of the cap of the housing. This application makes further improvements based on this.

[0004] This invention overcomes the shortcomings of the prior art and provides a novel cylindrical battery structure and battery pack, which has the advantages of simple structure and low cost. Utility Model Content

[0005] The main objective of this utility model is to provide a novel cylindrical battery structure, including a steel shell. The steel shell is a cylindrical structure with a hollow interior and an open end. A core is provided inside the steel shell, and a cover plate is provided at the opening of the steel shell. The core is connected to the bottom of the steel shell through a negative electrode current collector. The positive electrode current collector extends out a foldable connecting piece and is connected to the cover plate. A sealing ring is provided between the edge of the cover plate and the steel shell. The steel shell is provided with an explosion-proof groove.

[0006] Optionally, the positive current collector includes a disc body with a through hole in the middle and a first welding area recessed inward toward the core on the surface of the disc body, the first welding area being connected to the core; a connecting piece extends from the edge of the disc body, a first bending indentation is provided at the connection between the connecting piece and the disc body, a second welding area is provided at the end of the connecting piece, a second bending indentation is provided at the connection between the second welding area and the connecting piece, and the second welding area is connected to the cover plate.

[0007] Optionally, the connecting piece has reinforcing ribs on its surface.

[0008] Optionally, the negative electrode current collector has a third welding area in the middle that is concave towards the bottom of the steel shell, and a fourth welding area on the surface of the negative electrode current collector that is convex towards the core.

[0009] Optionally, the negative electrode current collector has concave symmetrical notches on both sides of its edge.

[0010] Optionally, the explosion-proof groove is located at the bottom of the steel shell, and the distance between the bottom of the explosion-proof groove and the inner surface of the bottom of the steel shell is 0.06-0.09 mm.

[0011] Optionally, the lower side of the sealing ring extends a foolproof region of a predetermined length around the periphery of the positive current collector, and the inner diameter of the foolproof region is larger than the area of ​​the folded connecting piece.

[0012] Optionally, the cover plate is provided with an injection hole, and the injection hole is provided with a sealing glue nail and a sealing aluminum nail, with the sealing aluminum nail located above the sealing glue nail.

[0013] Optionally, both the positive current collector and the cover plate are made of aluminum alloy.

[0014] This utility model also provides a battery pack, comprising several of the above-mentioned novel cylindrical battery structures.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The battery structure provided by this utility model connects the positive electrode current collector to the cover plate after folding it through a connecting piece. The positive electrode current collector and the connecting piece are integral structures made of the same material in one piece. Compared with the previous integral structure that welded connecting pieces and current collectors of different materials, the structure of this solution is further simplified. At the same time, an explosion-proof groove is set in the steel shell to cope with the high-pressure explosion prevention inside the battery, replacing the complex explosion-proof components and reducing the battery production cost. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is an exploded view of an embodiment of the cylindrical battery structure of this utility model; Figure 2 This is a cross-sectional view of an embodiment of the cylindrical battery structure of this utility model; Figure 3 This is a schematic diagram of the unfolded positive electrode current collector of an embodiment of the cylindrical battery structure of this utility model; Figure 4This is a schematic diagram of the unfolded positive electrode current collector of an embodiment of the cylindrical battery structure of this utility model; Figure 5 This is a schematic diagram of the negative electrode current collector of an embodiment of the cylindrical battery structure of this utility model; Figure 6 This is a schematic diagram showing the installation of the sealing ring and positive electrode current collector in an embodiment of the cylindrical battery structure of this utility model; Figure 7 This is a bottom view of an embodiment of the cylindrical battery structure of this utility model.

[0018] Figure label: 1-Steel shell; 11-Explosion-proof groove; 2-Roll core; 3-Cover plate; 31-Injection hole; 32-Sealing nail; 33-Sealing aluminum nail; 4-Positive electrode current collector; 40-Disc body; 41-Connecting piece; 411-Reinforcing rib; 42-Through hole; 43-First welding area; 44-First bending indentation; 45-Second welding area; 46-Second bending indentation; 5-Negative electrode current collector; 51-Third welding area; 52-Fourth welding area; 53-Notch; 6-Sealing ring; 61-Foolproof area. Detailed Implementation

[0019] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "connected to" another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "vertical," "horizontal," "left," "right," "inner," "outer," and similar expressions used in this specification are for illustrative purposes only. In the description of this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating relative importance or implying the number of indicated technical features. Thus, unless otherwise stated, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature; "multiple" means two or more. The term "comprising" and any variations thereof mean non-exclusive inclusion, where one or more other features, integers, steps, operations, units, components, and / or combinations thereof may be present or added.

[0020] Furthermore, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; as a mechanical connection or an electrical connection; as a direct connection or an indirect connection through an intermediate medium, or as a connection within two components. All technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0021] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0022] Conventional current collector connections to the cover plate require connecting tabs. During production, the connecting tabs need to be welded to the current collector and to the cover plate, requiring welding on both sides. Furthermore, the openings for the connecting tabs and the current collector need to be made separately. Alternatively, connecting tabs made of different materials can be welded to the current collector as a single unit, and then the connecting tabs can be folded before welding to the cover plate. This invention provides a battery structure embodiment that further simplifies the structure of the positive current collector. It is suitable for scenarios where both the cover plate and the positive current collector are made of aluminum alloy. In this case, both the positive current collector and the connecting tabs can be made of aluminum alloy. There is no need to additionally weld connecting tabs of different materials to the positive current collector to form a single unit. Instead, the connecting tabs and the positive current collector can be simultaneously processed and formed into a single unit during the positive current collector production process, simplifying the additional welding steps.

[0023] like Figure 1-7 The diagram shown is a schematic representation of an embodiment of the novel cylindrical battery structure provided by this utility model.

[0024] Please refer to Figure 1-7 This embodiment includes a steel shell 1, which is a cylindrical structure with a hollow interior and an open end. The steel shell 1 has a core 2 inside and a cover plate 3 at the opening. The core 2 is connected to the bottom of the steel shell 1 through a negative current collector 5. The positive current collector 4 extends out a foldable connecting piece 41 and is connected to the cover plate 3. A sealing ring 6 is provided between the edge of the cover plate 3 and the steel shell 1. The steel shell 1 is provided with an explosion-proof groove 11.

[0025] In one embodiment, the positive current collector 4 includes a disc body 40, with a through hole 42 in the middle of the disc body 40. The surface of the disc body 40 has a first welding area 43 that is recessed inward toward the core 2, and the first welding area 43 is connected to the core 2. A connecting piece 41 extends from the edge of the disc body 40. A first bending indentation 44 is provided at the connection between the connecting piece 41 and the disc body 40. A second welding area 45 is provided at the end of the connecting piece 41. A second bending indentation 46 is provided at the connection between the second welding area 45 and the connecting piece 41, and the second welding area 45 is connected to the cover plate 3.

[0026] Furthermore, the connecting piece 41 has reinforcing ribs 411 on its surface. The reinforcing ribs 411 are used to increase the bending strength of the connecting piece 41 itself and prevent it from bending when the connecting piece 41 is bent along the first bending indentation 44.

[0027] Specifically, such as Figure 3 As shown, the through hole 42 of the positive current collector 4 allows the electrolyte to flow into the winding core below. The first welding area 43 is symmetrically located on both sides of the through hole 42 in an arc shape, and the positive current collector 4 is laser-welded to the top of the winding core 2 through the first welding area 43. After bending, the connecting piece 41 is as follows: Figure 4 As shown, the connecting piece 41 is bent along the first bending indentation 44 and overlaps with the upper side of the positive current collector 4. The second welding area 45 is bent along the second bending indentation 46 and overlaps with the upper side of the connecting piece 41. The connecting piece 41 and the second welding area 45 overlap and form a Z-shaped cross-section with the positive current collector 4. The second welding area 45 is laser welded to the bottom surface of the cover plate 3.

[0028] In one embodiment, the negative electrode current collector 5 has a third welding area 51 that is concave inward toward the bottom of the steel shell 1 in the middle, and a fourth welding area 52 that is convex outward toward the core 2 on the surface of the negative electrode current collector 5. The third welding area 51 is circular and is connected to the bottom of the steel shell 1 by through welding. The fourth welding area 52 is an arc-shaped structure symmetrically located on both sides of the third welding area 51, and is laser welded to the bottom of the core 2.

[0029] Furthermore, the negative electrode current collector 5 has concave symmetrical notches 53 on both sides of its edge. The notches 53 are designed to facilitate the gripping and movement of the negative electrode current collector during the production process.

[0030] In one embodiment, such as Figure 7As shown, the explosion-proof groove 11 is located at the bottom of the steel shell 1. The distance between the bottom of the explosion-proof groove 11 and the inner surface of the bottom of the steel shell 1 is 0.06-0.09 mm, i.e., the residual amount is 0.06-0.09 mm. In this embodiment, 0.08 mm is preferred. The explosion-proof groove 11 is specifically obtained by pressing it into the bottom of the steel shell 1. When a fault occurs inside the steel shell 1 and high-pressure gas is generated, due to the thinness of the explosion-proof groove 11, it will burst under the action of high-pressure gas, thereby releasing the high pressure inside the steel shell 1 and preventing the steel shell 1 from exploding.

[0031] In one embodiment, the lower side of the sealing ring 6 extends a predetermined length of a foolproof region 61 surrounding the periphery of the positive current collector 4, such as... Figure 6 As shown, the inner diameter of the foolproof region 61 is larger than the area of ​​the folded connecting piece 41. The conventional sealing ring 6 serves to isolate the steel shell 1 from the cover plate 3 and seal the interior of the steel shell 1. This embodiment optimizes the sealing ring 6 by extending the foolproof region 61 to separate the positive current collector 4 connecting piece 41 from the steel shell 1, preventing a short circuit caused by improper bending of the connecting piece 41. Furthermore, if the connecting piece 41 is improperly bent, the foolproof region 61 will prevent the positive current collector 4 from being inserted into the steel shell 1. The sealing ring 6 is made of PBT material.

[0032] In one embodiment, the cover plate 3 is provided with an injection hole 31, and the injection hole 31 is provided with a sealing glue nail 32 and a sealing aluminum nail 33, with the sealing aluminum nail 33 located above the sealing glue nail 32. Electrolyte is injected into the steel shell 1 through the injection hole 31, and the injection hole 31 is sealed by the sealing glue nail 32 and the sealing aluminum nail 33.

[0033] In one embodiment, both the positive current collector 4 and the cover plate 3 are made of aluminum alloy.

[0034] This utility model also provides a battery pack embodiment, including several of the above-mentioned novel cylindrical battery structure embodiments. The multiple novel cylindrical battery structures constitute a battery pack which is packaged for use in subsequent power-consuming products, such as new energy vehicles or other electronic devices.

[0035] In summary, the embodiments provided by this utility model connect the positive current collector to the cover plate after folding it with a connecting piece. The positive current collector and the connecting piece are integral structures made of the same material in one process. Compared with the previous integral structure of welding connecting pieces and current collectors of different materials, the structure of this solution is further simplified. At the same time, an explosion-proof groove is set in the steel shell to cope with the high-voltage explosion protection inside the battery, replacing the complex explosion-proof components and reducing the battery production cost.

[0036] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Under the concept of this utility model, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this utility model as described above. For the sake of brevity, they are not provided in detail. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A novel cylindrical battery structure, characterized by, The application relates to a cylindrical battery structure, which comprises a steel shell, a winding core, a cover plate, a negative electrode current collector, a positive electrode current collector, a sealing ring and an anti-explosion groove.

2. The novel cylindrical battery structure according to claim 1, wherein, The positive electrode current collector comprises a disc body, a first welding area, a connecting sheet, a first bending mark, a second welding area and a second bending mark.

3. The novel cylindrical battery structure according to claim 2, wherein, The connecting sheet is provided with a reinforcing rib.

4. The novel cylindrical battery structure according to claim 1, wherein, The negative electrode current collector comprises a third welding area and a fourth welding area.

5. The novel cylindrical battery structure according to claim 4, wherein, The negative electrode current collector is provided with symmetrical concave notches on both side edges.

6. The novel cylindrical battery structure according to claim 1, wherein, The anti-explosion groove is arranged at the bottom of the steel shell, and the distance between the bottom of the anti-explosion groove and the inner side surface of the bottom of the steel shell is 0.06-0.09 mm.

7. The novel cylindrical battery structure according to claim 1, wherein The lower side of the sealing ring is provided with a fool-proof area with a predetermined length, which surrounds the periphery of the positive electrode current collector, and the inner diameter of the fool-proof area is larger than the area of the folded connecting sheet.

8. The novel cylindrical battery structure according to claim 1, wherein, The cover plate is provided with a liquid injection hole, the liquid injection hole is provided with a sealing rubber nail and a sealing aluminum nail, and the sealing aluminum nail is arranged on the upper side of the sealing rubber nail.

9. The novel cylindrical battery structure according to claim 1, wherein, The positive electrode current collector and the cover plate are made of aluminum alloy.

10. A battery pack characterized by comprising: The application further relates to a cylindrical battery structure comprising a plurality of the novel cylindrical battery structures.

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