Double-winding core cylindrical lithium battery structure

Abstract

The application relates to a double-winding-core cylindrical lithium battery structure and belongs to the technical field of new energy batteries. The double-winding-core cylindrical lithium battery structure comprises a metal cylindrical shell, the shell has an inner cavity with at least one open end, two winding cores are arranged in the inner cavity, a first electrode collecting disc of one winding core and a second electrode collecting disc of another winding core are arranged close to and spaced from each other, a through hole is formed in the first electrode collecting disc and corresponds to the inner cavity hole, a penetrating needle is arranged in the inner cavity hole and the through hole, the two ends of the penetrating needle are electrically connected to the second electrode collecting discs of the two winding cores respectively, the two first electrode collecting discs are electrically connected through the shell, and the penetrating needle is insulated from the inner wall of the inner cavity hole and the through hole and from the shell. The double-winding-core cylindrical lithium battery structure provided by the application realizes the parallel connection of the two winding cores through a simple structure, reduces the complex structural members used in the parallel connection structure of the traditional battery, and effectively improves the energy density of the cylindrical lithium battery.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy batteries, in particular to a double-winding-core cylindrical lithium battery structure. BACKGROUND

[0002] In today's era, with the problems of energy and environmental pollution, the automobile industry has undergone tremendous changes, and new energy vehicles have developed extremely rapidly, and more and more people have turned from fuel vehicles to new energy electric vehicles. New energy vehicles use batteries as a driving source, specifically installing battery modules on the car, and the battery module has multiple single batteries in series and parallel connection. In recent years, square batteries in new energy batteries have developed rapidly, but cylindrical batteries still occupy an important position in new energy batteries due to their structural characteristics and performance advantages.

[0003] In the application process of new energy batteries, in order to meet the voltage and capacity requirements, single lithium batteries are often arranged side by side in the battery pack to be connected in parallel, which increases the number of connecting pieces and reduces the energy density of the battery pack. And due to its structural characteristics, compared with square batteries, the conventional parallel connection method will form more gaps, further reducing the energy density of the battery pack. SUMMARY

[0004] 1. Problem to be solved

[0005] In view of the problem in the prior art that the traditional parallel connection of multiple single batteries increases the number of connecting pieces and reduces the energy density of the battery pack, the present application provides a double-winding-core cylindrical lithium battery structure, which can solve the problem of the need for more connecting pieces for parallel connection of two single batteries and further improve the battery energy density.

[0006] 2. Technical solution

[0007] To solve the above problems, the present application adopts the following technical solution.

[0008] A dual-core cylindrical lithium battery structure includes a metal cylindrical shell with an inner cavity open at least one end. A core is disposed within the inner cavity. Each core includes a main body, an inner cavity hole located at the axis of the main body, and first and second electrode current collectors located at opposite ends of the main body. Two cores are disposed within the inner cavity, with the first electrode current collector of one core and the second electrode current collector of the other core positioned close to each other and spaced apart. A through hole is formed on the first electrode current collector corresponding to the inner cavity hole. A through-pin passes through the inner cavity hole and the through hole, and its two ends are electrically connected to the second electrode current collectors of the two cores, respectively. The two first electrode current collectors are electrically connected through the shell. The through-pin is insulated from the inner walls of the inner cavity hole and the through hole, and from the second electrode current collectors to the shell. The two first electrode current collectors are electrically connected through the shell, and the two second electrode current collectors are electrically connected through the through-pin. The length of the through-pin is approximately the length of one core, reducing the number of structural components and significantly improving the energy density of the cylindrical lithium battery.

[0009] Furthermore, a support disk is provided in the inner cavity, and the support disk has support holes corresponding to the through holes and the inner cavity holes. The first electrode current collector and the second electrode current collector abut against both sides of the support disk. The first electrode current collector is electrically connected to the shell through the support disk, and the second electrode current collector is insulated from the support disk. This achieves insulation between the two current collectors and better supports the two winding cores, improving the structural strength of the battery.

[0010] Furthermore, the support disk includes a flat portion that contacts the first electrode current collector, a side portion located around the periphery of the flat portion, and a bent portion located at the other end of the side portion, with an insulating layer disposed between the bent portion and the second electrode current collector.

[0011] Furthermore, a gap is left between the inner wall of the through hole, support hole, and inner cavity hole and the insertion needle.

[0012] Furthermore, an insulating layer is provided on the inner wall of the through hole and the support hole.

[0013] Furthermore, the first electrode current collector, the second electrode current collector, and the support plate are all provided with a number of wetting holes.

[0014] Furthermore, a cover plate is provided at one end of the housing opening, and a through hole is provided on the corresponding second electrode current collector for the insertion needle to pass through. The second electrode current collector of the other core is connected to the insertion needle.

[0015] Furthermore, the cover plate is provided with a mating hole through which the insertion needle passes, and a pole post that matches and connects with the insertion needle is provided in the mating hole. An insulating liner is also provided between the pole post and the wall of the mating hole.

[0016] Further, the first electrode current collector disc away from the supporting disc is provided with a supporting side plate on the side surface of the shell end.

[0017] Further, the shell is open at both ends, and the first electrode current collector disc away from the supporting disc is provided with a sealing plate sealing the opening of the shell, and the sealing plate is provided with a supporting pad cooperating with the supporting side plate to support and fix the first electrode current collector disc.

[0018] 3, beneficial effects

[0019] Compared with the prior art, the beneficial effects of the present application are:

[0020] (1) The double-winding core cylindrical lithium battery structure provided by the present application has two winding cores arranged in one shell, realizes parallel connection of the two winding cores through a simple structure, reduces the complex structural parts used in the parallel connection structure of the traditional battery, and in the present application, the first electrode current collector disc of one winding core and the second electrode current collector disc of another winding core are opposite to each other, the two first electrode current collector discs are electrically connected through the shell, the two second electrode current collector discs are electrically connected through the penetrating needle, and the length of the penetrating needle is only the length of one winding core, which further reduces the structure weight and effectively improves the energy density of the cylindrical lithium battery.

[0021] (2) The double-winding core cylindrical lithium battery structure provided by the present application is provided with a supporting disc between the two winding cores, which can realize insulation between the two current collector discs on the one hand, and better support the two winding cores on the other hand, improve the structural strength of the battery, and the infiltration holes are arranged on the first electrode current collector disc, the second electrode current collector disc and the supporting disc, which not only reduces the weight of the structural parts, but also facilitates the infiltration of the electrolyte, and has strong popularization and application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a structure schematic view of the double-winding core cylindrical lithium battery structure of the present embodiment;

[0023] Figure 2 It is a structure schematic view of the double-winding core cylindrical lithium battery structure of the present embodiment hidden behind the winding core body;

[0024] Figure 3 It is a structure schematic view of the double-winding core cylindrical lithium battery structure of the present embodiment at the connection between the two winding cores;

[0025] Figure 4 It is a structure composition diagram of the shell part of the double-winding core cylindrical lithium battery structure of the present embodiment;

[0026] Figure 5 It is a structure schematic view of the sealing plate part of the double-winding core cylindrical lithium battery structure of the present embodiment;

[0027] Figure 6It is a structure schematic view of the support disc in the double-winding core cylindrical lithium battery structure of the embodiment;

[0028] Figure 7 It is a structure schematic view of the winding core body in the double-winding core cylindrical lithium battery structure of the embodiment;

[0029] Figure 8 It is a structure schematic view of the winding core body connecting the first electrode current collecting disc in the double-winding core cylindrical lithium battery structure of the embodiment;

[0030] Figure 9 It is a structure schematic view of the winding core body connecting the second electrode current collecting disc and the penetrating needle in the double-winding core cylindrical lithium battery structure of the embodiment.

[0031] In the figure:

[0032] 1, shell; 2, inner cavity; 3, main body; 4, inner cavity hole; 5, first electrode current collecting disc; 6, second electrode current collecting disc; 7, through hole; 8, penetrating needle; 9, support disc; 901, support hole; 902, flat part; 903, side part; 904, bending part; 10, insulation layer; 11, gap; 12, infiltration hole; 13, cover plate; 14, pole; 15, insulation lining; 16, support side plate; 17, sealing plate; 18, support cushion. DETAILED DESCRIPTION

[0033] In order to make the technical means, creative features, purposes and effects of the present application easy to understand, the present application will be further described below in combination with embodiments.

[0034] At present, in the production process of cylindrical lithium batteries, a process of placing a bare winding core inside a single aluminum shell is often used. This process has the following defects: too many structural parts are required, and it is difficult to improve the energy density.

[0035] The winding core is an electric core formed in a winding manner, which is the main part of the cylindrical lithium battery, and includes a winding core body, an inner cavity hole at the axis of the winding core body, a negative electrode lug, and a positive electrode lug. The materials of the negative electrode lug and the positive electrode lug are copper and aluminum, respectively. During processing, the negative electrode lug and the positive electrode lug need to be flattened, which can be done by ultrasonic flattening or mechanical flattening. Then, the negative electrode lug is connected to the negative electrode current collecting disc, and the positive electrode lug is connected to the positive electrode current collecting disc to lead out the current.

[0036] The embodiment provides a double-winding core cylindrical lithium battery structure, which comprises a metal cylindrical shell 1, the shell 1 has an inner cavity 2 with at least one open end, and a winding core is arranged in the inner cavity 2, such as Figures 7-9As shown, the winding core includes a main body 3, an inner cavity hole 4 at the center of the main body 3, and a first electrode current collector 5 and a second electrode current collector 6 at both ends of the main body 3. It should be noted that the metal cylindrical shell 1 in the embodiment can be integrally formed, or can be formed by splicing two half shells 1, and can be processed and adjusted according to actual needs. The first electrode current collector 5 and the second electrode current collector 6 at both ends of the main body 3 are connected to the corresponding tabs. In addition, the winding core in the embodiment represents a winding core group, which can be a single winding core or a plurality of winding cores connected in series, and only the first electrode current collector 5 and the second electrode current collector 6 at both ends of the winding core group are needed.

[0037] The focus of the embodiment is that two winding cores are arranged in the inner cavity 2, as shown in the figure, Figures 1-3 As shown, the first electrode current collector 5 of one winding core and the second electrode current collector 6 of another winding core are arranged close to and spaced from each other, and a support disc 9 can be arranged between the two, and the first electrode current collector 5 and the second electrode current collector 6 are respectively abutted on both sides of the support disc 9. On the one hand, it can realize the insulation between the first electrode current collector 5 and the second electrode current collector 6, and on the other hand, it can better support the two winding cores and improve the structural strength of the battery.

[0038] In a possible embodiment, as shown in the figure, Figure 6 As shown, the support disc 9 includes a flat portion 902 in contact with the first electrode current collector 5, a side edge portion 903 located on the side of the flat portion 902, and a bent portion 904 located at the other end of the side edge portion 903. During processing, the disc-shaped structural member can be bent, or a plurality of structural members can be welded. In addition, an insulating layer 10 is arranged between the bent portion 904 and the second electrode current collector 6, so as to realize the insulation therebetween.

[0039] In addition, a through hole 7 is formed in the first electrode current collector 5 corresponding to the inner cavity hole 4, and a support hole 901 is formed in the support disc 9 corresponding to the through hole 7 and the inner cavity hole 4. The support hole 901, the inner cavity hole 4 and the through hole 7 pass through the insertion needle 8, and the two ends of the insertion needle 8 are respectively electrically connected to the second electrode current collectors 6 of the two winding cores. Specifically, the insertion needle 8 is fixedly connected to the second electrode current collector 6 close to the first electrode current collector 5, and the second electrode current collector 6 of the other winding core is provided with a current collector perforation for the insertion needle 8 to pass through. During assembly, the stable connection of the two winding cores can be realized through the cooperation of the two second electrode current collectors 6 and the insertion needle 8. In order to ensure the insulation between the inner wall of the winding core inner cavity hole 4, the first electrode current collector 5 and the insertion needle 8, a gap 11 is left between the through hole 7, the support hole 901, the inner wall of the inner cavity hole 4 and the insertion needle 8. An insulating layer 10 can be further arranged on the inner wall of the through hole 7, the support hole 901 and the inner cavity hole 4.

[0040] As for the first electrode current collectors 5 of the two cores, they are electrically connected through the housing 1. Specifically, the first electrode current collector 5 near the second electrode current collector 6 can be directly abutted against the inner wall of the inner cavity 2 of the housing 1, or it can be electrically connected to the housing 1 through the support plate 9. The first electrode current collector 5 of the other core is directly abutted against the inner wall of the inner cavity 2 of the housing 1, thereby realizing the electrical connection of the two first electrode current collectors 5.

[0041] The housing 1 may be open at one end or open at both ends, wherein a cover plate 13 needs to be provided at the opening at one end of the housing 1, such as... Figure 4 As shown, the second electrode current collector 6, which is far from the support plate 9, is located close to it. The current collector hole on the second electrode current collector 6 is pierced by the insertion needle 8. A mating hole through which the insertion needle 8 passes is provided on the cover plate 13. An electrode post 14 that matches and connects with the insertion needle 8 is provided in the mating hole. An insulating liner 15 is also provided between the electrode post 14 and the wall of the mating hole, thereby realizing the assembly of the electrode post 14 structure. In addition, an injection hole and an explosion-proof valve are also required on the cover plate 13.

[0042] When shell 1 is open at both ends, such as Figure 5 As shown, a sealing plate 17 is provided on the other end of the housing 1 opposite to the cover plate 13. Corresponding to the sealing plate 17 is the first electrode current collector 5 away from the support plate 9. A support side plate 16 is provided on its side facing the end of the housing 1. Correspondingly, a support pad 18 is provided on the sealing plate 17 to cooperate with the support side plate 16 to support and fix the first electrode current collector 5.

[0043] After the two cores are assembled in the housing 1, electrolyte needs to be injected into the core body 3 in the inner cavity 2 through the injection hole on the cover plate 13. Because the two cores are long, the electrolyte penetration speed is slow. Therefore, several wetting holes 12 are provided on the first electrode current collector 5, the second electrode current collector 6 and the support plate 9 to facilitate the passage of electrolyte and reduce the structural weight.

[0044] In the description of this patent, it should be understood that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "front", "back", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this patent.

[0045] In this patent, unless specifically defined and limited otherwise, the terms "mounting", "connected", "connecting", "fixed", and the like, should be interpreted broadly, for example, can be fixed connection, can also be detachable connection, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meaning of the above terms in this patent can be understood according to the specific circumstances.

[0046] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those of ordinary skill in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements should fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A dual-core cylindrical lithium battery structure, comprising a metal cylindrical shell (1), the shell (1) having an inner cavity (2) open at least one end, a core disposed in the inner cavity (2), the core comprising a main body (3), an inner cavity hole (4) located at the axis of the main body (3), and a first electrode current collector (5) and a second electrode current collector (6) located at both ends of the main body (3), characterized in that, Two winding cores are provided in the inner cavity (2). The inner cavity holes (4) of the two winding cores are arranged along the same axis. The first electrode current collector (5) of one winding core and the second electrode current collector (6) of the other winding core are arranged close to each other and spaced apart. The first electrode current collector (5) has a through hole (7) corresponding to the inner cavity hole (4). The insert pin (8) passes through the inner cavity hole (4) and the through hole (7). The two ends of the insert pin (8) are electrically connected to the second electrode current collectors (6) of the two winding cores respectively. The two first electrode current collectors (5) are electrically connected through the housing (1). The insertion needle (8) is insulated from the inner wall of the inner cavity (4) and the through hole (7), and from the second electrode current collector (6) and the housing (1); wherein the length of the insertion needle (8) is the length of a single core, a support plate (9) is provided in the inner cavity (2), the second electrode current collector (6) and the support plate (9) are insulated, the first electrode current collector (5) and the second electrode current collector (6) respectively abut against the two sides of the support plate (9), the first electrode current collector (5) is directly electrically connected to the housing (1), or electrically connected to the housing (1) through the support plate (9).

2. The dual-core cylindrical lithium battery structure according to claim 1, characterized in that, The support plate (9) has a support hole (901) corresponding to the through hole (7) and the inner cavity hole (4). The first electrode current collector (5) and the second electrode current collector (6) are respectively abutted against the two sides of the support plate (9). The first electrode current collector (5) is electrically connected to the shell (1) through the support plate (9).

3. The dual-core cylindrical lithium battery structure according to claim 2, characterized in that, The support plate (9) includes a flat portion (902) that contacts the first electrode current collector (5), a side portion (903) located around the flat portion (902), and a bent portion (904) located at the other end of the side portion (903). An insulating layer (10) is provided between the bent portion (904) and the second electrode current collector (6).

4. The dual-core cylindrical lithium battery structure according to claim 2 or 3, characterized in that, A gap (11) is left between the inner wall of the through hole (7), the support hole (901), the inner cavity hole (4) and the insertion needle (8).

5. The dual-core cylindrical lithium battery structure according to claim 4, characterized in that, An insulating layer (10) is provided on the inner wall of the through hole (7) and the support hole (901).

6. The dual-core cylindrical lithium battery structure according to claim 4, characterized in that, The first electrode collector (5), the second electrode collector (6) and the support plate (9) are each provided with a number of wetting holes (12).

7. The dual-core cylindrical lithium battery structure according to claim 1, characterized in that, The housing (1) has a cover plate (13) at one end of the opening, and the corresponding second electrode current collector (6) has a current collector hole for the insertion needle (8) to pass through. The second electrode current collector (6) of the other core is connected to the insertion needle (8).

8. The dual-core cylindrical lithium battery structure according to claim 7, characterized in that, The cover plate (13) is provided with a mating hole through which the insertion needle (8) passes. A pole post (14) that matches and connects with the insertion needle (8) is provided in the mating hole. An insulating liner (15) is also provided between the pole post (14) and the wall of the mating hole.

9. The dual-core cylindrical lithium battery structure according to claim 2, characterized in that, A support side plate (16) is provided on the side of the first electrode collector (5) away from the support plate (9) facing the end of the housing (1).

10. The dual-core cylindrical lithium battery structure according to claim 9, characterized in that, The housing (1) is open at both ends. The first electrode current collector (5) away from the support plate (9) is provided with a sealing plate (17) to close the opening of the housing (1). The sealing plate (17) is provided with a support pad (18) that cooperates with the support side plate (16) to support and fix the first electrode current collector (5).

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