A cylindrical battery

Abstract

The utility model relates to battery technology field especially, it relates to a cylindrical battery, main include: casing, current collecting disc, roll core and positioning ring, in the utility model, through setting up a positioning ring in roll core hole, the positioning ring guides the welding needle to the predetermined welding position through loudspeaker big mouth, guide cone surface and loudspeaker small mouth, ensure that the welding needle repeatedly positions to the same fixed point every time, and then reduce the welding position deviation, improve the welding quality, and also make the current collecting disc import low internal resistance, low -cost copper nickel plating material also become possible.

Description

Technical Field

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

[0002] Currently, lithium-ion / sodium-ion cylindrical batteries have become mainstream products in the new energy field due to their high energy density, excellent capacity consistency, and high-rate charge / discharge capabilities. The structure of a cylindrical battery mainly includes several parts: the core, the current collector, and the battery casing. The core and current collector are fixed using laser welding. To meet the market's urgent demand for high production capacity, the current collector is generally connected to the bottom of the battery casing using resistance welding, thus forming a current path from the core to the battery casing.

[0003] Resistance welding is a relatively fast connection method. In automated production lines, efficiency is improved by first inserting pins for positioning and then welding them one by one. That is, the resistance welding pin is first inserted into the battery casing, positioned above the current collector along the center hole of the core, and then resistance welding is performed one by one.

[0004] However, resistance welding has significant limitations. Due to the limited positioning accuracy of the welding needle, the tip of the needle will randomly land in any area of ​​the current collector below the center hole of the core during each welding operation. It is impossible to guarantee that the welding needle will land on the same fixed point every time. Different landing points will lead to instability in the resistance welding process (such as inconsistent weld nugget size, spatter, etc.) or directly cause poor welding. During use (especially the vibration of electric vehicles), the heavier core inside the battery will generate inertial force, causing it to bounce up and down inside the battery casing, continuously impacting the weld joint. This can easily cause the weld joint to fall off, ultimately leading to open circuit failure of the battery and posing a serious safety hazard. Utility Model Content

[0005] The purpose of this invention is to provide a cylindrical battery to solve the problems mentioned in the background art.

[0006] The technical solution adopted in this utility model is:

[0007] A cylindrical battery, comprising:

[0008] The shell has a hollow internal structure, with one end being an open end and the other end being a closed end;

[0009] A collector plate is disposed inside the housing, on which a core is disposed, and a core hole is provided through the core, and a positioning ring is disposed inside the core hole;

[0010] in,

[0011] The positioning ring is used to achieve precise positioning of the welding needle.

[0012] Optionally, the collector disk includes:

[0013] The main body of the collector plate has a first connection area and a second connection area. The first connection area is fitted to the closed end of the housing, and the second connection area is connected to the winding core.

[0014] Optionally, the second connection area is an upper boss structure.

[0015] Optionally, a positioning notch is provided on the main body of the collector plate.

[0016] Optionally, the first connecting area is a concave frustum structure with a diameter of 1.8~2.5mm.

[0017] Optionally, the positioning ring includes:

[0018] The large flare opening is located inside the core hole;

[0019] The flared opening is located inside the core hole and corresponds to the first connection area;

[0020] The guide cone has one end connected to the edge of the large opening of the horn and the other end connected to the edge of the small opening of the horn.

[0021] Optionally, the outer diameter of the horn opening is equal to the inner diameter of the core hole minus 0.15~0.5mm.

[0022] Optionally, the inner diameter of the horn opening is equal to the end diameter of the welding needle plus 0.1~0.35mm.

[0023] Optionally, the inner diameter of the horn opening is smaller than the diameter of the first connecting area.

[0024] Optionally, the collector plate is made of nickel-plated copper, and / or the positioning ring is made of PP or PPS.

[0025] Compared with the prior art, the beneficial effects of this utility model are:

[0026] In this invention, a positioning ring is set in the core hole. The positioning ring guides the welding needle to the predetermined welding position through the large horn opening, the guide cone surface and the small horn opening, ensuring that the welding needle is repeatedly positioned on the same fixed point each time, thereby reducing welding position deviation and improving welding quality. At the same time, it also makes it possible to introduce low internal resistance and low cost copper-plated nickel material into the collector plate. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the overall structure of this application;

[0029] Figure 2 This is a schematic diagram of the collector disk structure in this application;

[0030] Figure 3 This is a schematic diagram of the positioning ring in this application;

[0031] Figure 4 This is a schematic diagram of the structure of an embodiment of this application.

[0032] Figure label:

[0033] 1. Shell; 11. Open end; 12. Closed end;

[0034] 2. Data collection panel; 21. Data collection panel body; 211. Positioning notch; 22. First connection area; 23. Second connection area;

[0035] 3. Core; 31. Core hole;

[0036] 4. Positioning ring; 41. Large flare opening; 42. Small flare opening; 43. Guide cone surface;

[0037] 5. Welding needles. Detailed Implementation

[0038] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.

[0039] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0040] Currently, due to the limited positioning accuracy of resistance welding needles, the tip of the resistance welding needle will randomly fall on any area of ​​the current collector plate below the center hole of the core during each welding operation. It is impossible to accurately guarantee that the resistance welding needle will fall on the same fixed point every time. Different landing points will lead to instability in the resistance welding process or directly cause the problem of incomplete welding.

[0041] like Figures 1-4 As shown, this utility model embodiment provides a cylindrical battery, which mainly includes: a shell 1, a current collector 2, a winding core 3, and a positioning ring 4, etc.

[0042] The housing 1 is a hollow columnar structure with an open end 11 and a closed end 12. A current collector 2 is located inside the closed end 12 (i.e., the bottom of the housing 1), and a winding core 3 is mounted on the current collector 2. A winding core hole 31 is formed through the center of the winding core 3. The current collector 2 connects the housing 1 and the winding core 3, thus forming a current path from the winding core 3 to the housing 1. The winding core 3 is configured as the core site for the battery's charge-discharge reaction (lithium-ion insertion / deintercalation). Its structure and working principle are existing technologies and will not be described in detail in this embodiment.

[0043] A positioning ring 4 is provided at one end of the core hole 31 near the collector plate 2 (that is, at the bottom of the core hole 31). The positioning ring 4 is configured to precisely guide the welding needle 5 to the predetermined welding position, ensuring that the welding needle 5 is repeatedly positioned at the same fixed point each time, thereby reducing welding position deviation and improving welding quality.

[0044] Specifically, such as Figure 2 As shown, the collector plate 2 mainly includes: collector plate body 21, first connection area 22 and second connection area 23, etc.

[0045] The main body 21 of the collector plate is provided with a first connecting area 22 and a second connecting area 23. The first connecting area 22 is attached to the closed end 12 of the housing 1. The second connecting area 23 surrounds the first connecting area 22 and is connected to the tab on the winding core 3.

[0046] The first connecting area 22 is a concave frustum structure, and the diameter of the frustum is preferably 1.8~2.5mm. The first connecting area 22 is welded to the closed end 12 (bottom end) of the shell 1 by resistance welding. There are multiple second connecting areas 23, which are evenly distributed along the circumference. The second connecting area 23 is an upper boss structure, and the second connecting area 23 is fixedly connected to the tabs on the core 3 by laser welding.

[0047] Furthermore, a positioning notch 211 is provided on the main body 21 of the collector plate, located at the edge of the main body 21. The positioning notch 211 is used to provide positioning during welding, and can also serve as a positioning structure for material handling when installing the collector plate 2. For example, when installing the collector plate 2, a robotic arm transfers the collector plate 2 from the placement station to the installation station. The robotic arm can grip the positioning notch 211 of the collector plate 2, and the positioning notch 211 can serve as a recognition feature when the robotic arm performs machine vision recognition. During the welding of the collector plate 2 and the core 3, and the welding of the collector plate 2 and the shell 1, the welding robot can identify and position the components through the positioning notch 211.

[0048] Furthermore, for the purpose of reducing costs and improving battery internal resistance (to meet the requirements of high-rate charging and discharging of the battery), the current collector 2 in this embodiment is made of copper plated with nickel.

[0049] Specifically, when the material of the manifold 2 is copper plated with nickel, the thickness of the manifold 2 is 0.15mm, the end diameter of the welding needle 5 is 3mm, and the welding current is 2.8 (KA), the welding time is 8 (ms), and the welding pressure is 15 (N), a stable weld connection can be obtained.

[0050] like Figure 3 As shown, the positioning ring 4 mainly includes: a large horn opening 41, a small horn opening 42, and a guide cone surface 43 connecting the edges of the large horn opening 41 and the small horn opening 42.

[0051] The flared opening 41 is located inside the core hole 31, and its outer diameter is smaller than the inner diameter of the core hole 31. Preferably, the outer diameter of the flared opening 41 is equal to the inner diameter of the core hole 31 minus (0.15~0.5mm).

[0052] The flared opening 42 is located inside the core hole 31 and corresponds to the first connection area 22. The inner diameter of the flared opening 42 is larger than the end diameter of the welding needle 5. Preferably, the inner diameter of the flared opening 42 is equal to the end diameter of the welding needle 5 plus (0.1~0.35mm).

[0053] Furthermore, to ensure precise positioning of the welding needle 5 during insertion, the edges of both the large flare opening 41 and the small flare opening 42 are chamfered in this embodiment. The chamfered guide slope allows the welding needle 5 to slide smoothly into the positioning ring 4 and settle into the final welding position.

[0054] Furthermore, in order to further improve the positioning accuracy of the welding pin 5, in this embodiment, the inner diameter of the flared opening 42 is smaller than the diameter of the first connecting area 22 (that is, the diameter of the frustum).

[0055] Furthermore, in this embodiment, the positioning ring 4 is made of insulating plastics such as PP or PPS. PP or PPS has excellent dielectric strength and insulation properties, which can effectively block the current path between the welded housing 1 and the current collector 2, preventing internal short circuits in the battery. During resistance welding, a large current flows through the welding contact surface between the housing 1 and the current collector 2. The insulating positioning ring 4 ensures that the current flows concentratedly through the preset welding path, preventing it from leaking into non-target areas, thereby ensuring welding quality (such as avoiding incomplete welds and spatter) and protecting the welding equipment (such as preventing short circuit damage).

[0056] Furthermore, the positioning ring 4 in this embodiment is manufactured using an injection molding process.

[0057] When using, such as Figure 4 As shown, first, the positioning ring 4 is placed into the core hole 31, with the flared opening 42 facing the bottom of the core hole 31. Then, the second connecting area 23 in the collector plate 2 is laser welded to the core 3. Subsequently, the core 3 and the collector plate 2 are placed together inside the housing 1, so that the first connecting area 22 of the collector plate 2 is in contact with the closed end 12 of the housing 1. The welding needle 5 passes through the core hole 31 and is guided by the positioning ring 4 to the welding position (the part where the first connecting area 22 is in contact with the closed end 12 of the housing 1). Finally, a large current is applied and transmitted by the welding needle 5 to the welding contact surface between the housing 1 and the collector plate 2 to perform welding.

[0058] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A cylindrical battery, characterized in that, include: The housing has a hollow internal structure, with one end open and the other end closed; the collector plate is disposed inside the housing, on which a core is disposed, and a core hole is formed through the core, with a positioning ring disposed inside the core hole; The positioning ring is used to achieve precise positioning of the welding needle.

2. The cylindrical battery according to claim 1, characterized in that, The collector plate includes: a collector plate body, on which a first connection area and a second connection area are provided, the first connection area being fitted to the closed end of the housing, and the second connection area being connected to the winding core.

3. The cylindrical battery according to claim 2, characterized in that, The second connection area is an upper boss structure.

4. The cylindrical battery according to claim 2, characterized in that, The main body of the collector plate has a positioning notch.

5. The cylindrical battery according to claim 2, characterized in that, The first connecting area is a concave frustum structure with a diameter of 1.8~2.5mm.

6. The cylindrical battery according to claim 5, characterized in that, The positioning ring includes: a large horn opening located inside the core hole; a small horn opening located inside the core hole, corresponding to the first connecting area; and a guide cone surface, one end of which is connected to the edge of the large horn opening and the other end of which is connected to the edge of the small horn opening.

7. The cylindrical battery according to claim 6, characterized in that, The outer diameter of the horn opening is equal to the inner diameter of the core hole minus 0.15~0.5mm.

8. The cylindrical battery according to claim 6, characterized in that, The inner diameter of the horn opening is equal to the end diameter of the welding needle plus 0.1~0.35mm.

9. The cylindrical battery according to claim 6, characterized in that, The inner diameter of the horn opening is smaller than the diameter of the first connecting area.

10. The cylindrical battery according to claim 1, characterized in that, The collector plate is made of nickel-plated copper, and / or the positioning ring is made of PP or PPS.

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