Cylindrical battery monomer and battery module

Abstract

The utility model relates to the field of batteries, and discloses a cylindrical battery monomer and a battery module, the cylindrical battery monomer comprises a shell, a first pole cover and a second pole cover, the shell is provided with a containing cavity, the containing cavity is provided with a first opening and a second opening, a battery cell is arranged in the containing cavity, the first pole cover is fixedly arranged at the position of the first opening of the shell, and the second pole cover is fixedly arranged at the position of the second opening of the shell. The first pole cover seals the first opening, the second pole cover is fixedly arranged at the position of the second opening of the shell, the second pole cover seals the second opening, and a notch groove is formed in the surface, away from the direction of the battery cell, of the second pole cover. The notch groove is formed in the end surface, deviating from the battery cell direction, of the second pole cover, so that the strength of the second pole cover at the notch groove position is reduced, the pressure is more easily released from the second pole cover position, and the battery is protected.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of batteries, in particular to a cylindrical battery monomer and a battery module. BACKGROUND

[0002] With the vigorous development of new energy automobile industry and the increasing maturity of super fast charging technology, higher requirements are put forward for the charging efficiency and energy density of power batteries. The aluminum shell cylindrical battery cell has obvious advantages in improving the weight energy density, reducing the ohmic resistance and optimizing the heat dissipation efficiency due to the characteristics of light weight, high thermal conductivity and low resistivity of the shell material, and has become a research hotspot in the field of power batteries.

[0003] However, the aluminum shell battery cell has obvious deficiencies in strength and melting point compared with the traditional steel shell. Especially in the situation of thermal runaway, the existing pressure relief valve of the aluminum shell battery cell design adopts a local end face burst disc, and its pressure relief capacity is limited, which is difficult to quickly and effectively release the internal pressure, leading to the easy rupture of the side of the battery cell, and further causing the heat spread between the battery cells in the battery pack, seriously threatening the safety and stability of the battery system. UTILITY MODEL CONTENT

[0004] Therefore, the purpose of the present application is to overcome the deficiencies in the prior art and provide a cylindrical battery monomer and a battery module.

[0005] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0006] The present application provides:

[0007] A cylindrical battery monomer comprises:

[0008] A shell having a containing cavity, the containing cavity having a first opening and a second opening, and an electric cell arranged in the containing cavity;

[0009] A first pole cover fixedly arranged at the first opening position of the shell, the first pole cover closing the first opening;

[0010] A second pole cover fixedly arranged at the second opening position of the shell, the second pole cover closing the second opening, and a notch being formed on the surface of the second pole cover away from the electric cell.

[0011] Further, the first pole cover comprises a first cover plate fixedly arranged at the first opening, an injection hole being formed through the first cover plate, and a sealing ball being arranged in the injection hole, the sealing ball being used for plugging the injection hole.

[0012] Further, the second pole cover comprises a second cover plate fixedly arranged at the second opening position, the notch is arranged on an end face of the second cover plate away from the direction of the battery cell, a mounting hole is arranged on the second cover plate and penetrates the second cover plate, and an insulating sealing element is arranged between the outer circumferential surface of the pole post and the inner wall of the mounting hole.

[0013] Further, the distance between the inner bottom wall of the notch and the end face of the second cover plate close to the direction of the battery cell is L, and 60 μm≤L≤300 μm is satisfied.

[0014] Further, a first connecting assembly is arranged between the battery cell and the second pole cover, the second pole cover is connected with the battery cell through the first connecting assembly, the first connecting assembly comprises a first current collecting plate arranged at the end of the battery cell, an insulating sleeve is arranged at the position of the first current collecting plate, a first connecting handle is connected between the first current collecting plate and the second pole cover, and the first current collecting plate is connected with the second pole cover through the first connecting handle.

[0015] Further, a second connecting assembly is arranged between the first pole cover and the battery cell, the first pole cover is connected with the battery cell through the second connecting assembly, the second connecting assembly comprises a second current collecting plate connected with the battery cell, a second connecting handle is connected between the second current collecting plate and the first pole cover, and the second current collecting plate is connected with the first pole cover through the second connecting handle.

[0016] Further, the second current collecting plate comprises a disc body, a plurality of uniformly arranged protrusions are arranged on the disc body, and a first through hole is arranged between adjacent two protrusions.

[0017] Further, a second through hole is arranged at the center of the disc body, and at least one communication groove is arranged on the outer circumferential surface of the disc body.

[0018] Further, the disc body has a connecting area, the connecting area is in the shape of a sector, the angle of the connecting area is α, and 60°≤α≤120° is satisfied.

[0019] The application also provides a battery module comprising the cylindrical battery cell.

[0020] The application reduces the strength of the second pole cover at the position of the notch by arranging the notch on the end face of the second pole cover away from the direction of the battery cell, so that the pressure is more easily released from the position of the second pole cover, and the battery is protected.

[0021] In order to make the above-mentioned purposes, characteristics and advantages of the application more obvious and easy to understand, the following preferred embodiments are described in detail below, and the accompanying drawings are described as follows. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be considered as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0023] Figure 1 An explosion state structure schematic diagram of the battery cell of the present application is shown;

[0024] Figure 2 A cross-sectional view schematic diagram of the battery cell of the present application is shown;

[0025] Figure 3 A first pole cover structure schematic diagram of the present application is shown;

[0026] Figure 4 A second pole cover structure schematic diagram of the present application is shown;

[0027] Figure 5 A second pole cover cross-sectional view schematic diagram of the present application is shown;

[0028] Figure 6 A first current collecting disc and a second current collecting disc structure schematic diagram of the present application is shown.

[0029] Main element symbol explanation: 100, housing; 110, battery cell; 200, first pole cover; 210, first cover plate; 220, liquid injection hole; 230, sealing ball; 300, second pole cover; 310, second cover plate; 320, mounting hole; 330, pole; 340, insulating sealing element; 400, groove; 500, first connecting assembly; 510, first current collecting disc; 520, insulating sleeve; 530, first connecting handle; 600, second connecting assembly; 610, second current collecting disc; 611, disc body; 612, boss; 613, first through hole; 614, second through hole; 615, communication groove; 616, connecting area; 620, second connecting handle. DETAILED DESCRIPTION

[0030] The embodiments of the present application will be described in detail below, examples of which are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation on the present application.

[0031] In the description of the present application, it needs to be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0032] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise explicitly specified and limited.

[0033] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0034] In the present application, unless otherwise explicitly specified and limited, the first feature "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "above", "over" and "on" the second feature can be that the first feature is directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "under" and "under" the second feature can be that the first feature is directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0035] In the design of the existing cylindrical battery, the pressure relief valve is usually only provided with a local burst piece on the end face, which is not sufficient to achieve rapid pressure relief, thereby causing the battery to burst from the side, which may further cause the battery to catch fire and other phenomena.

[0036] The embodiment of the present application provides a cylindrical battery monomer, which comprises a shell 100, a first pole cover 200 and a second pole cover 300, wherein the shell 100 has a containing cavity, the containing cavity has a first opening and a second opening, an electric core 110 is arranged in the containing cavity, the first pole cover 200 is fixedly arranged at the first opening position of the shell 100, the first pole cover 200 seals the first opening, the second pole cover 300 is fixedly arranged at the second opening position of the shell 100, the second pole cover 300 seals the second opening, and a notch 400 is arranged on the surface of the second pole cover 300 away from the electric core 110.

[0037] Referring to FIGS. 1, 2 and 3, Figure 1 and Figure 4 The electric core 110 is arranged in the containing cavity of the shell 100, the first pole cover 200 and the second pole cover 300 are arranged at two ends of the containing cavity, specifically, the first pole cover 200 is a negative pole end, the second pole cover 300 is a positive pole end, and a notch 400 is arranged on the surface of the second pole cover 300 away from the electric core 110, the notch 400 is coaxial with the second pole cover 300, and the strength of the surface of the second pole cover 300 can be reduced through the notch 400, when the pressure in the containing cavity reaches a certain value, the second pole cover 300 is rapidly broken at the position of the notch 400, so that the pressure in the containing cavity is released, the pressure in the containing cavity cannot burst the side surface of the shell 100, and combustion or explosion is prevented, thereby achieving the effect of protecting the battery.

[0038] In some embodiments, the first pole cover 200 and the second pole cover 300 are directly and continuously welded with the shell 100, so that the machining process of the structural member is greatly simplified, the cost of the structural member is reduced, the difficulty of the welding process is reduced, and the production efficiency is improved.

[0039] In some embodiments, the first pole cover 200 is a plane, and the shell 100 is made of aluminum material and has good thermal conductivity, so that the plane water cooling plate can be used for cooling or heating from the bottom, and the conventional serpentine water cooling plate of the cylindrical battery is not needed, and the design cost of the module can be greatly reduced.

[0040] The first pole cover 200 comprises a first cover plate 210 fixedly arranged at the first opening, an injection hole 220 is arranged on the first cover plate 210 and penetrates the first cover plate 210, and a sealing ball 230 is arranged in the injection hole 220 and used for plugging the injection hole 220.

[0041] Referring to FIGS. 1, 2 and 3, Figure 1 , Figure 2 , and Figure 3As shown, after the first cover plate 210 is connected at the opening of the accommodating cavity and the second cover plate 300 is connected at the other opening, electrolyte can be injected into the accommodating cavity through the liquid injection hole 220 in communication with the accommodating cavity, so as to realize injection of the electrolyte. After the electrolyte is injected, the liquid injection hole 220 is closed by the sealing ball 230. Specifically, the sealing ball 230 is in interference fit with the liquid injection hole 220, so as to realize closing of the liquid injection hole 220.

[0042] The second cover plate 300 includes a second cover plate 310 fixedly arranged at the second opening position. The notch 400 is arranged on the end face of the second cover plate 310 away from the battery cell 110. The second cover plate 310 is provided with a mounting hole 320 penetrating the second cover plate 310. The mounting hole 320 is provided with a pole 330. An insulating sealing member 340 is arranged between the outer circumferential surface of the pole 330 and the inner wall of the mounting hole 320.

[0043] Referring to Figure 2 and Figure 5 As shown, the second cover plate 310 is provided with a stepped face at the edge, so as to better adapt to the outer edge of the shell 100, facilitate welding, and the pole 330 is arranged in the mounting hole 320 of the second cover plate 310. Specifically, the pole 330 can be connected with the mounting hole 320 in the riveting mode, and the insulating sealing member 340 can be arranged between the pole 330 and the inner wall of the mounting hole 320 to realize sealing and insulation. The material of the insulating sealing member 340 is not limited here, and any material capable of realizing insulation and sealing can be used.

[0044] The distance between the inner bottom wall of the notch 400 and the end face of the second cover plate 310 close to the battery cell 110 is L, and satisfies 60 μm≤L≤300 μm.

[0045] Referring to Figure 5 As shown, in order to ensure that the pressure can be discharged from the second cover plate 300 at the position of the notch 400 when pressure relief is performed, the strength of the second cover plate 300 at the position of the notch 400 needs to be designed. Therefore, the distance between the inner bottom wall of the notch 400 and the end face of the second cover plate 310 close to the battery cell 110 satisfies a certain requirement. Specifically, the distance can be 60 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, etc.

[0046] The first connecting assembly 500 is arranged between the electric core 110 and the second pole cover 300, the second pole cover 300 is connected with the electric core 110 through the first connecting assembly 500, the first connecting assembly 500 comprises a first current collector plate 510 arranged at the end of the electric core 110, an insulating sleeve 520 is arranged at the position of the first current collector plate 510, the first current collector plate 510 is connected with the second pole cover 300 through a first connecting handle 530, and the first current collector plate 510 is connected with the second pole cover 300 through the first connecting handle 530.

[0047] Referring to Figure 1 and Figure 2 As shown in the drawings, in order to release the electric energy stored in the electric core 110, the electric core 110 needs to be connected with the pole 330 of the second pole cover 300, specifically, a first current collector plate 510 is arranged at the end of the electric core 110, specifically, the first current collector plate 510 is connected with the electric core 110 in a laser welding manner, in order to prevent the first current collector plate 510 from being connected with the shell 100, an insulating sleeve 520 with a hollow intermediate portion is arranged at the position of the first current collector plate 510, the first current collector plate 510 is located inside the insulating sleeve 520, so as to isolate the first current collector plate 510 from the shell 100 and achieve insulation, further, in order to connect the first current collector plate 510 with the pole 330, the first current collector plate 510 is connected with the pole 330 through a first connecting handle 530.

[0048] In one embodiment, the first connecting handle 530 is an aluminum strip.

[0049] The second connecting assembly 600 is arranged between the first pole cover 200 and the electric core 110, the first pole cover 200 is connected with the electric core 110 through the second connecting assembly 600, the second connecting assembly 600 comprises a second current collector plate 610 connected with the electric core 110, the second current collector plate 610 is connected with the first pole cover 200 through a second connecting handle 620, and the second current collector plate 610 is connected with the first pole cover 200 through the second connecting handle 620.

[0050] Please continue to refer to Figure 1 and Figure 2 As shown in the drawings, the first cover plate 210 of the first pole cover 200 serves as a negative electrode, the second current collector plate 610 is connected with the electric core 110 in the direction of the end of the electric core 110 towards the first cover plate 210, specifically, the second current collector plate 610 is connected with the electric core 110 in a laser welding manner, and in order to connect the second current collector plate 610 with the first cover plate 210, the second current collector plate 610 is connected with the first cover plate 210 through the second connecting handle 620, it should be noted that the second connecting handle 620 should avoid the liquid injection hole 220 when being connected with the first cover plate 210, so as to prevent the liquid injection hole 220 from being closed.

[0051] In one embodiment, the second connecting handle 620 can be a copper strip.

[0052] In the embodiment, the second current collector 610 has the same structure as the first current collector 510, the first current collector 510 is an aluminum alloy or a nickel-plated aluminum alloy, and the second current collector 610 is copper or nickel-plated copper.

[0053] The second current collector 610 comprises a disc body 611, a plurality of uniformly arranged bosses 612 are arranged on the disc body 611, and a first through hole 613 is arranged between adjacent two bosses 612.

[0054] Referring to Figure 6 In order to be able to adapt to the pole piece of the battery cell 110, a plurality of bosses 612 are arranged on the disc body 611, the bosses 612 are in a protruding state, so as to be in full contact with the battery cell 110, realize full connection with the battery cell 110, and in order to enable the electrolyte to enter the inside of the shell 100, the first through hole 613 is arranged on the disc body 611, the first through hole 613 is located between adjacent two bosses 612, and the size of the boss 612 is not limited here, and can be designed according to the actual situation.

[0055] In one embodiment, the boss 612 is formed in a stamping manner, or other forming manners, which are not limited here, such as Figure 6 As shown in the figure, the boss 612 has five, and is uniformly arranged on the disc body 611.

[0056] The disc body 611 is provided with a second through hole 614 at the center, and at least one communication groove 615 is arranged on the outer periphery of the disc body 611.

[0057] Referring to Figure 6 In order to further facilitate the electrolyte to enter the inside of the shell 100, the second through hole 614 is arranged at the center of the disc body 611, and the communication groove 615 is arranged at the outer periphery edge of the disc body 611, so as to further increase the communication with the accommodating cavity of the shell 100, and make the electrolyte more convenient to enter the inside of the shell 100.

[0058] The disc body 611 is provided with a connecting area 616, the connecting area 616 is a sector, the angle occupied by the connecting area 616 is α, and satisfies: 60°≤α≤120°.

[0059] Please continue to refer to Figure 6As shown, since the second connecting handle 620 needs to be connected with the disc body 611 of the second current collector 610, in order to prevent the second connecting handle 620 from blocking the first through hole 613, or the second through hole 614 and the communication groove 615, a connecting area 616 is further arranged on the disc body 611, and no other components are arranged at the position of the connecting area 616, the position of the connecting area 616 is a plane, so as to facilitate the connection between the second connecting handle 620 and the disc body 611, and the second connecting handle 620 and the disc body 611 can be connected in a laser welding mode.

[0060] The area of the connecting area 616 on the disc body 611 can be represented by an angle, specifically, the connecting area 616 is a sector, and the angle a of the sector can be 60°, 70°, 80°, 90°, 100°, 110°, 120°, etc., and the specific angle value is not limited herein.

[0061] The embodiments of the present application further provide a battery module, which comprises the cylindrical battery cell according to any one of the above.

[0062] It can be understood that the battery module comprises the cylindrical battery cell according to the above, and therefore the battery module has the technical effects of the cylindrical battery cell, and the technical effects will not be described herein again, and the details can be referred to the above description of the cylindrical battery cell.

[0063] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0064] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application, and the person skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A cylindrical battery cell, characterized by, The application relates to a battery shell. The shell (100) has a containing cavity with a first opening and a second opening, and an electric core (110) is arranged in the containing cavity. A first pole cover (200) is fixedly arranged at the first opening position of the shell (100), and the first pole cover (200) seals the first opening. A second pole cover (300) is fixedly arranged at the second opening position of the shell (100), and the second pole cover (300) seals the second opening.

2. The cylindrical battery cell according to claim 1, characterized in that, The first pole cover (200) comprises a first cover plate (210) fixedly arranged at the first opening, and a liquid injection hole (220) is arranged on the first cover plate (210) and penetrates the first cover plate (210).

3. The cylindrical battery cell of claim 1, wherein, The second pole cover (300) comprises a second cover plate (310) fixedly arranged at the second opening position, and a notch (400) is arranged on the end face of the second cover plate (310) away from the electric core (110).

4. The cylindrical battery cell of claim 3, wherein, The second cover plate (310) is provided with a mounting hole (320) penetrating the second cover plate (310), and a pole column (330) is arranged in the mounting hole (320).

5. The cylindrical battery cell of claim 1, wherein, An insulating sealing element (340) is arranged between the outer circumferential surface of the pole column (330) and the inner wall of the mounting hole (320). The distance between the inner bottom wall of the notch (400) and the end face of the second cover plate (310) close to the electric core (110) is L, and the following condition is met: 60 mu m <= L <= 300 mu m. A first connecting assembly (500) is arranged between the electric core (110) and the second pole cover (300), the second pole cover (300) is connected with the electric core (110) through the first connecting assembly (500), the first connecting assembly (500) comprises a first current collecting disc (510) arranged at the end of the electric core (110), an insulating sleeve (520) is arranged at the position of the first current collecting disc (510), a first connecting handle (530) is connected between the first current collecting disc (510) and the second pole cover (300), and the first current collecting disc (510) is connected with the second pole cover (300) through the first connecting handle (530).

6. The cylindrical battery cell of claim 1, wherein, A second connecting assembly (600) is arranged between the first pole cover (200) and the battery cell (110), the first pole cover (200) and the battery cell (110) are connected through the second connecting assembly (600), the second connecting assembly (600) comprises a second current collector (610) connected with the battery cell (110), the second current collector (610) and the first pole cover (200) are connected through a second connecting handle (620), and the second current collector (610) and the first pole cover (200) are connected through the second connecting handle (620).

7. The cylindrical battery cell of claim 6, wherein, The second current collector (610) comprises a disc body (611), a plurality of uniform bosses (612) are arranged on the disc body (611), and a first through hole (613) is arranged between adjacent two bosses (612).

8. The cylindrical battery cell of claim 7, wherein, A second through hole (614) is arranged at the center of the disc body (611), and at least one communication groove (615) is arranged on the outer circumferential surface of the disc body (611).

9. The cylindrical battery cell of claim 7, wherein, The disc body (611) is provided with a connecting area (616), the connecting area (616) is a sector, the angle occupied by the connecting area (616) is α, and 60°≤α≤120° is satisfied.

10. A battery module, characterized by The cylindrical battery cell comprises the cylindrical battery cell according to any one of claims 1 to 9.

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