Cylindrical battery

Abstract

The utility model discloses a cylindrical battery which comprises a positive collector plate and a positive pole, and the positive collector plate and the positive pole are connected through a limiting structure for limiting the positive collector plate and the positive pole. The positive collector plate comprises a positive collector plate body, a convex part and a positive collector plate through hole, the positive pole comprises a positive pole body, a positive pole sinking table, an inner concave part and a positive pole through hole, the convex part and the inner concave part are connected together, and the convex part and the inner concave part can be welded, glued, clamped and the like. According to the cylindrical battery structure provided by the utility model, the positive pole and the positive collector plate can be stably matched together, deviation is prevented, positioning, limiting and fixing effects are achieved, so that the problems of internal short circuit and the like of the battery caused by deviation between the positive pole and the positive collector plate are prevented, and the cylindrical battery structure has the effects of easiness in control in the assembly process, simplicity in operation, high welding yield and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of battery structures, and particularly relates to a cylindrical battery. Background Art

[0002] The cylindrical lithium-ion battery with full tab is a commonly used structure at present. However, the problem faced by the cylindrical battery with full tab structure is how to realize the connection between the tab and the cover plate pole column. Therefore, the current collector plate becomes the key to connecting the battery tab and the cover plate pole column. The currently common current collector plates are disc-shaped or square-shaped. During battery assembly, the current collector plate is placed at the center of the end face of the battery tab, and then one end of the current collector plate and the battery tab are welded into a whole by laser welding. The other end of the current collector plate is connected to the pole column of the cover plate by welding or riveting. Furthermore, through the connection of the battery tab, the current collector plate, and the pole column, the cylindrical lithium-ion battery realizes sealing and current circuit.

[0003] However, in the existing cylindrical battery structure, the positioning between the positive current collector plate and the positive pole column is prone to deviation, resulting in poor welding between the positive pole column and the positive current collector plate, and posing a risk of short circuit in the subsequent finished battery. Summary of the Utility Model

[0004] Aiming at the technical problem that in the existing cylindrical battery structure, the positioning between the positive current collector plate and the positive pole column is prone to deviation pointed out in the above background art, the purpose of the utility model is to provide a cylindrical battery.

[0005] To achieve the above purpose, the technical solution provided by the utility model is as follows:

[0006] A cylindrical battery, comprising a positive current collector plate and a positive pole column, wherein the positive current collector plate and the positive pole column are connected through a limiting structure for limiting the positive current collector plate and the positive pole column.

[0007] Optionally, the limiting structure includes a protruding portion provided on the positive current collector plate and a concave portion provided on the positive pole column, and the protruding portion is located within the concave portion and the two are used in cooperation.

[0008] Optionally, the connection manner between the protruding portion and the concave portion is welding, gluing or clamping.

[0009] Optionally, the number of the protruding portions is 2-8, and the number of the concave portions is the same as that of the protruding portions and the positions correspond one by one.

[0010] Optionally, the number of the protruding portions is an even number and is arranged in central symmetry.

[0011] Optionally, the height of the protruding portion is 0.1 mm - 0.6 mm, and correspondingly, the concave depth of the concave portion is 0.1 mm - 0.6 mm.

[0012] Optionally, the shape of the protruding portion is circular, rhombic or polygonal. Correspondingly, the shape of the concave portion is consistent with that of the protruding portion.

[0013] Optionally, the protruding portion adopts one of the following structures:

[0014] The first type: the protruding portion is annular. Correspondingly, the concave portion is annular.

[0015] The second type: the protruding portion is cylindrical and rotatable, and external threads are provided on the outer circumferential surface thereof. Correspondingly, internal threads are provided on the inner circumferential surface of the concave portion. The protruding portion and the concave portion are threadedly connected through the cooperation of the external threads and the internal threads.

[0016] Optionally, the positive current collector plate includes a positive current collector plate body, a protruding portion and a through hole of the positive current collector plate. Among them, the through hole of the positive current collector plate is concentric with the liquid injection hole, and the diameter of the through hole of the positive current collector plate is larger than the diameter of the liquid injection hole.

[0017] Optionally, the positive electrode post includes a positive electrode post body, a sunken platform of the positive electrode post, a concave portion and a through hole of the positive electrode post. Among them, the positive electrode post body is connected to the negative electrode cover plate. The sunken platform of the positive electrode post is a downward sunken platform. A liquid injection hole is provided at the center of the sunken platform of the positive electrode post. The concave portion is located on the sunken platform of the positive electrode post.

[0018] Compared with the prior art, the beneficial effects of the present utility model are:

[0019] The cylindrical battery structure provided by the present utility model can enable the positive electrode post and the positive current collector plate to be stably fitted together, prevent deviation, play a role in positioning, limiting and fixing, thereby preventing problems such as internal short circuit of the battery caused by deviation between the two, and having effects such as easy control in the assembly process, simple operation and high welding yield. Description of the Drawings

[0020] Figure 1 It is the first schematic diagram of the structure of the positive current collector plate in Embodiment 1 of the present application;

[0021] Figure 2 It is the second schematic diagram of the structure of the positive current collector plate in Embodiment 1 of the present application;

[0022] Figure 3 It is the first schematic diagram of the structure of the positive electrode post in Embodiment 1 of the present application;

[0023] Figure 4 It is the second schematic diagram of the structure of the positive electrode post in Embodiment 1 of the present application;

[0024] Figure 5 It is the third schematic diagram of the structure of the positive electrode post in Embodiment 1 of the present application;

[0025] Figure 6 It is a schematic structural diagram of the positive current collector plate in Embodiment 2 of the present application;

[0026] Figure 7 It is a schematic structural diagram of the positive electrode post in Embodiment 2 of the present application;

[0027] Figure 8 It is the first schematic diagram of the assembly structure of the positive electrode post and the positive current collector plate in Embodiment 2 of the present application;

[0028] Figure 9 It is the second schematic diagram of the assembly structure of the positive electrode post and the positive current collector plate in Embodiment 2 of the present application;

[0029] Figure 10 It is a schematic diagram of the assembly structure of the positive electrode post and the positive current collector plate in Embodiment 2 of the present application;

[0030] Figure 11 It is a schematic diagram of the assembly structure of the positive electrode post and the positive current collector plate in Embodiment 3 of the present application;

[0031] In the figure, there are positive current collector plate body 1, protruding part 2, positive current collector plate through hole 3, positive electrode post through hole 4, positive electrode post body 5, positive electrode post sunk platform 6, concave part 7, insulating glue 8, and negative electrode cover plate 9. Specific embodiments

[0032] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0033] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model.

[0034] In the description of this patent, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", "linkage", and "setting" should be understood in a broad sense. For example, it can be fixedly connected and set, or detachably connected and set, or integrally connected and set. For those of ordinary skill in the art, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0035] Embodiment 1

[0036] As Figures 1 - 5 shown, it is the structural diagram of the embodiment provided by the present utility model.

[0037] The cylindrical battery provided in this embodiment includes a positive current collector plate and a positive electrode post. The positive current collector plate and the positive electrode post are connected through a limiting structure for limiting the positive current collector plate and the positive electrode post.

[0038] The limiting structure includes a protruding portion 2 provided on the positive current collector plate and a concave portion 7 provided on the positive electrode post. The protruding portion 2 is located within the concave portion 7 and the two are used in cooperation.

[0039] In a preferred embodiment, the positive current collector plate includes a positive current collector plate body 1, a protruding portion 2, and a positive current collector plate through hole 3. Among them, the positive current collector plate through hole 3 is concentrically arranged with the liquid injection hole. The diameter of the liquid injection hole is 2 mm - 5 mm, and the diameter of the through hole is slightly larger than that of the liquid injection hole, being 2.2 mm - 5.2 mm, which is convenient for injecting the electrolyte into the interior of the battery cell. Preferably, the diameter of the liquid injection hole can be set to 2 mm, 3 mm, 4 mm, etc. Correspondingly, the diameter of the positive current collector plate through hole 3 can be set to 2.5 mm, 3.5 mm, 4.5 mm, etc. If the diameter is set too small, it is not easy to inject the electrolyte. If the diameter is set too large, the strength of both will be reduced, and they are prone to deformation and rupture, etc.

[0040] In a preferred embodiment, the protruding portion 2 is located on the side of the positive current collector plate body 1 facing away from the battery cell and towards the positive electrode post. The number of protruding portions 2 is set to 2 - 8, and among them, an even number is optimal and they are symmetrically arranged about the center. Preferably, the number of protruding portions 2 is set to 2, 4, or 6, and they are symmetrically arranged about the center of the positive current collector plate. Among them, the height of the protruding portion 2 is 0.1 mm - 0.6 mm, and the shape can be circular, rhombic, polygonal, etc., which is the same as and matches the shape of the concave portion 7. Preferably, the height of the protruding portion 2 is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, etc. If the protruding portion 2 is too low, it cannot play a limiting and fixing role. If it is too high, it will occupy too much space of the battery, resulting in low space utilization rate and low battery energy density, etc.; the positive current collector plate body 1 is a circular structure, covering the end face of the positive electrode tab of the battery cell and connecting with the positive electrode tab. The connection method can be laser welding, ultrasonic welding, etc.

[0041] In a preferred embodiment, the positive electrode post includes a positive electrode post body 5, a positive electrode post sunk platform 6, a concave portion 7, and a positive electrode post through hole 4. The positive electrode post body 5 is connected to the negative electrode cover plate through an insulating adhesive, and the connection method can be riveting, gluing, etc.; the positive electrode post sunk platform 6 is a sunken platform with a depth of 0.4 - 1.0 mm for placing a sealing nail for sealing. A liquid injection hole is provided at the center of the positive electrode post sunk platform 6 for injecting electrolyte into the battery interior; the concave portion 7 is located on the positive electrode post sunk platform 6, close to the side of the positive current collector plate. There are 2 - 8 concave portions 7, and an even number is optimal. Preferably, there are 2, 4, or 6 concave portions 7, which are symmetric about the center of the positive current collector plate. The concave depth of the concave portion 7 is 0.1 - 0.6 mm, and the shape can be circular, diamond-shaped, polygonal, etc., which is the same as and matches the shape of the protruding portion 2. Preferably, the depth of the concave portion 7 is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, etc. If the concave portion 7 is too low, it cannot play a role in limiting and fixing. If it is too high, the strength of the positive electrode post will be reduced, and it will occupy too much battery space, resulting in low space utilization rate and low battery energy density, etc.

[0042] In a preferred embodiment, the protruding portion 2 and the concave portion 7 are connected together, and the connection method between the two can be welding, gluing, snap connection, etc. The connection method between the protruding portion 2 and the concave portion 7 can be laser welding, and the laser welding area is the overlapping area of the protruding portion 2 of the positive current collector plate and the concave portion 7 of the positive electrode post; the two can be in interference fit, which can save the welding process between the positive current collector plate and the positive electrode post, optimize the process flow, and save costs.

[0043] It should be noted that the cylindrical battery case is a cylinder with one end open. The closed end is connected to the negative current collector plate through laser penetration welding; the other end is open for accommodating the battery cell and is connected to the positive electrode post cover assembly. The negative electrode cover in the positive electrode post cover assembly covers the open end of the case, and the two are connected together.

[0044] The manufacturing process of the cylindrical battery is as follows:

[0045] The positive current collector, separator, and negative current collector are wound into an electrode core in a certain order. After the electrode core is flattened or patted flat, the positive and negative electrode tabs on both sides are welded to the positive and negative current collector plates respectively, and the welding method is laser welding. Then, the positive electrode post cover assembly (positive electrode post + insulating glue + negative cover plate) is assembled with the electrode core after being welded to the positive current collector plate. The positive electrode post cover assembly is placed in the accommodation cavity formed by the limiting parts of the positive current collector plate. Then, at the sunken position of the positive electrode post, the positive electrode post cover assembly is welded to the positive current collector plate, and the welding method is laser welding, and the welding area is the overlapping area of the two. After the positive electrode post cover assembly and the positive current collector plate are assembled, they are put into the shell. After being put into the shell, the negative current collector plate is laser penetration welded to the bottom of the shell, and the welding direction is from the bottom of the shell, so that the bottom of the shell is connected to the negative current collector plate. Then, the negative cover plate of the positive electrode post cover assembly is peripherally welded to the shell, so that the battery is assembled. This assembly method can not only make the positive electrode post and the positive current collector plate cooperate stably with each other to prevent deviation, but also first weld the positive current collector plate and the positive electrode tab of the electrode core, assemble and weld the positive electrode post and the positive current collector plate, and then put them into the shell, which can make the positive electrode post and the positive current collector plate cooperate stably, the assembly process is easy to control and simple to operate, etc., and prevent problems such as internal short circuit of the battery caused by deviation between the two.

[0046] Among them, the materials of the cylindrical battery shell, negative electrode tab, and negative current collector plate can be stainless steel, copper, nickel, nickel-plated stainless steel, nickel-plated copper, etc., and the materials of the positive electrode tab and positive electrode post can be aluminum / aluminum alloy.

[0047] Embodiment 2

[0048] As Figures 6 - 10 shown, it is the structural diagram of the embodiment provided by the present utility model.

[0049] The cylindrical battery provided by this embodiment includes a positive current collector plate and a positive electrode post, and the positive current collector plate and the positive electrode post are connected through a limiting structure for limiting the positive current collector plate and the positive electrode post.

[0050] The limiting structure includes a protruding part 2 arranged on the positive current collector plate and a concave part 7 arranged on the positive electrode post. The protruding part 2 is located in the concave part 7 and the two are used in cooperation.

[0051] The protruding part 2 is cylindrical, and an external thread is arranged on the outer circumferential surface thereof. Correspondingly, an internal thread is arranged on the inner circumferential surface of the concave part 7, and the protruding part 2 and the concave part 7 are threadedly connected through the external thread and the internal thread. It should be noted that the number of protruding parts is 1.

[0052] For convenient operation, the protruding part 2 can be set as a rotatable structure.

[0053] As Figure 10As shown, it is a schematic diagram of the assembly structure of the positive electrode post and the positive current collector plate. An insulating adhesive (8) is provided between the negative electrode cover plate (9), the positive electrode post, and the main body of the positive current collector plate.

[0054] It should be noted that for the other structures of the cylindrical battery, reference can be made to the description in Embodiment 1, which will not be elaborated here.

[0055] Embodiment 3

[0056] As Figure 11 shown, it is the structure of the embodiment provided by the present utility model.

[0057] The cylindrical battery provided in this embodiment includes a positive current collector plate and a positive electrode post, and the positive current collector plate and the positive electrode post are connected through a limiting structure for limiting the positive current collector plate and the positive electrode post.

[0058] The limiting structure includes a protruding portion 2 provided on the positive current collector plate and a concave portion 7 provided on the positive electrode post. The protruding portion 2 is located within the concave portion 7 and the two are used in cooperation.

[0059] The protruding portion 2 is circular, and correspondingly, the concave portion 7 is circular for accommodating the protruding portion 2.

[0060] It should be noted that for the other structures of the cylindrical battery, reference can be made to the description in Embodiment 1, which will not be elaborated here.

[0061] The above shows and describes the basic principles, main features, and advantages of the present utility model. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present utility model and do not limit the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A cylindrical battery, characterized in that: The invention comprises a positive current collector disk and a positive electrode column, wherein the positive current collector disk and the positive electrode column are connected via a limiting structure for limiting the positive current collector disk and the positive electrode column; the limiting structure comprises a protrusion (2) arranged on the positive current collector disk and an inner recess (7) arranged on the positive electrode column, the protrusion (2) is located in the inner recess (7), and the two are used in coordination; The protrusion (2) adopts one of the following structures: The first type: the number of the protrusions (2) is an even number and they are arranged in a centrally symmetrical manner; the protrusions (2) are in a circular ring shape, and matchingly, the inner recess (7) is in a circular ring shape; The second type: the protruding portion (2) is cylindrical, and an external thread is arranged on its outer circumferential surface. Matchingly, an internal thread is arranged on the inner circumferential surface of the inner recessed portion (7). The protruding portion (2) and the inner recessed portion (7) are threadedly connected by matching external threads and internal threads.

2. A cylindrical battery according to claim 1, characterized in that: The protruding portion (2) and the inner recessed portion (7) are connected by welding, gluing or clamping.

3. A cylindrical battery according to claim 1, characterized in that: The number of the protrusions (2) is 2 to 8, and the number of the inner recesses (7) is consistent with that of the protrusions (2), and the positions correspond one to one.

4. A cylindrical battery according to claim 1, characterized in that: The height of the protruding portion (2) is 0.1 mm-0.6 mm, and correspondingly, the depth of the concave portion (7) is 0.1 mm-0.6 mm.

5. A cylindrical battery according to claim 1, characterized in that: The shape of the protruding portion (2) is circular, rhombus-shaped or polygonal, and matchingly, the shape of the inner recess (7) is consistent with that of the protruding portion (2).

6. A cylindrical battery according to claim 1, characterized in that: The positive current collecting disc comprises a positive current collecting disc body (1), a protruding portion (2) and a positive current collecting disc through hole (3), wherein the positive current collecting disc through hole (3) is arranged concentrically with the injection hole, and the diameter of the positive current collecting disc through hole (3) is larger than the diameter of the injection hole.

7. A cylindrical battery according to claim 1, characterized in that: The positive electrode column comprises a positive electrode column body (5), a positive electrode column sink (6), an inner recess (7) and a positive electrode column through hole (4), wherein the positive electrode column body (5) is connected to a negative electrode cover plate (9), the positive electrode column sink (6) is a concave sink, a liquid injection hole is arranged at the center of the positive electrode column sink (6), and the inner recess (7) is located on the positive electrode column sink (6).

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