A cylindrical battery structure

Abstract

This utility model discloses a cylindrical battery structure, relating to the technical field of lithium-ion batteries. It includes a single-through housing with a cross-section of three tangent circles. The single-through housing contains an upward-opening battery cavity. The lower end face of the single-through housing has several cross-shaped recessed areas. A liquid injection hole is located at the center of the lower end face of the single-through housing. A negative electrode cover plate is connected to the upper side of the single-through housing. The negative electrode cover plate includes a negative current collector, and a substrate aluminum sheet is connected to the negative current collector. The substrate aluminum sheet and the single-through housing are snap-fitted together. This utility model uses a 3-in-1 honeycomb structure to achieve maximum space utilization at the cell-level and module-level, while reducing the cost of the housing structure components. Simultaneously, the cell structure is simplified: the positive current collector is eliminated, and the bottom of the single-through housing serves as both the cover plate and the current collector; the core is directly welded to the stamping area at the bottom of the housing; an explosion-proof valve and a liquid injection hole are integrated; the negative current collector structure is simplified by forming a thin sheet through simple stamping.

Description

Technical Field

[0001] This utility model relates to the technical field of lithium-ion batteries, and in particular to a cylindrical battery structure. Background Technology

[0002] Due to its high energy density, the 4680 cylindrical battery cell, with its single-cell design utilizing all tabs, significantly reduces internal resistance, improves power, safety, and fast-charging performance. Currently, all major battery manufacturers are developing 4680 cylindrical cells. However, during module or pack assembly, the cells cannot be tightly bonded together, resulting in low module or pack volume utilization (this space is currently mostly used for heat dissipation materials or structural fixation). Furthermore, to achieve the high energy density of cylindrical cells, the main cell material is mostly high-compact materials, leading to poor electrolyte wetting, longer wetting times, and greater difficulty in electrolyte injection. Additionally, the extreme utilization of internal space within the cell results in less free electrolyte, posing potential risks to cycle performance.

[0003] Among existing patents, such as the cylindrical battery cell structure and its manufacturing method disclosed in CN118748299A, multiple cores are placed in the same housing and then combined to reduce material and simultaneously increase telecommunications energy density.

[0004] However, in existing patents, the petal-shaped housing structure for battery integration is wasteful, leading to the accumulation of wasted space in the module pack assembly; the complex battery current collector results in excessively high structural component costs in the BOM. Utility Model Content

[0005] Purpose of the invention: The purpose of this utility model is to provide a cylindrical battery structure that solves the problems of wasted battery space and complex current collector structure.

[0006] Technical solution

[0007] A cylindrical battery structure includes a single-through housing with a cross-section of three tangent circles. The single-through housing has an upward-opening battery cavity. The lower end face of the single-through housing has several cross-shaped recessed areas. The center of the lower end face of the single-through housing has an injection hole. A negative electrode cover plate is connected to the upper side of the single-through housing. The negative electrode cover plate includes a negative current collector. A substrate aluminum sheet is connected to the negative current collector. The substrate aluminum sheet and the single-through housing are snapped together.

[0008] Furthermore, a sealing aluminum sheet is welded to the injection hole, and the surface of the sealing aluminum sheet is marked.

[0009] Furthermore, a lower plastic layer is provided between the negative current collector and the aluminum substrate, and the diameter of the negative current collector and the lower plastic layer is slightly smaller than that of the aluminum substrate.

[0010] Furthermore, the negative collector is provided with a bending strip, which folds over and abuts against the lower plastic.

[0011] Furthermore, the upper surface of the lower plastic is provided with a boss, and the boss abuts against the aluminum sheet of the substrate.

[0012] Furthermore, the negative electrode cover plate also includes a negative electrode post, the boss is provided with an annular countersunk hole, a sealing ring is connected inside the annular countersunk hole, and a through hole is provided in the center of the aluminum substrate sheet.

[0013] Furthermore, the negative current collector has a circular through hole at its center, and the negative electrode post passes through the circular through hole, the sealing ring, and the through hole of the aluminum sheet of the substrate in sequence. The negative electrode post and the negative electrode cover are riveted together.

[0014] Furthermore, the negative electrode post is connected to an upper plastic layer above the aluminum substrate.

[0015] Furthermore, a riveted aluminum block is connected above the upper plastic post to the negative electrode post.

[0016] Beneficial effects: The use of a 3-in-1 honeycomb structure maximizes the space utilization of the cell-level module while reducing the cost of the housing structure; at the same time, it simplifies the cell structure: the positive electrode current collector is eliminated, and a single-pass bottom of the housing is used as the cover plate and current collector, with the core directly welded to the stamping area at the bottom of the housing; explosion-proof valve and liquid injection hole are integrated; the negative electrode current collector structure is simplified, and the current collector sheet is formed by simple stamping. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is a bottom view of the single-through housing structure of this utility model;

[0019] Figure 3 This is a schematic diagram of the negative collector disk structure of this utility model;

[0020] Figure 4 This is a schematic diagram of the rice bucket shell structure of this utility model.

[0021] Reference numerals: 1. Sealing aluminum sheet; 2. Single-pass housing; 202. Cross-shaped recessed area; 203. Injection hole; 3. Negative manifold; 301. Circular through hole; 302. Flanged groove; 303. Bending strip; 4. Lower plastic; 401. Boss; 402. Annular countersunk hole; 5. Sealing ring; 6. Negative electrode post; 7. Substrate filter; 8. Upper plastic; 9. Riveted aluminum block. Detailed Implementation

[0022] To make the technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Example

[0023] like Figure 1-4 As shown, a cylindrical battery structure includes a single-pass shell 22 with a cross-section of three tangent circles. The outer transition circle is the size of the three inscribed small circles, forming a 1 / 6 honeycomb shape. The single-pass shell 22 has an upward-opening battery cavity, which is used to place the core.

[0024] A circular recessed hole is provided at the center of the bottom of the battery cavity, and an injection hole 203 is provided at the circular recessed hole, through which electrolyte can be injected into the battery cavity.

[0025] The bottom wall of the battery cavity is the positive electrode of the cylindrical battery. A cross-shaped sinking area 202 is provided on the bottom wall of the battery cavity. The bottom of the three circular parts is also provided with a cross-shaped sinking area 202, and the three cross-shaped sinking areas 202 are connected at the center. The circular sinking hole and the cross-shaped sinking area 202 are connected. The core electrode tab is welded to the cross-shaped sinking area 202 to ensure that the core can work normally.

[0026] A sealing aluminum sheet 1 is connected to the lower end face of the single-pass housing 22. The sealing aluminum sheet 1 is a circular thin sheet, which is integrally stamped and formed. The outer surface of the thin sheet has shallow grooves and integrates the functions of sealing the liquid injection hole and explosion prevention. The sealing aluminum sheet is embedded in the circular countersunk hole at the bottom of the single-pass housing 2 for splicing and welding.

[0027] A negative electrode cover plate is connected to the upper side of the single-pass housing 22. The negative electrode cover plate includes a negative current collector 3. The shape of the negative current collector 3 is the same as the cross-sectional shape of the single-pass housing 22, but the size of the negative current collector 3 is smaller than that of the single-pass housing 22. The negative current collector 3 is embedded in the single-pass housing 22 for easy connection with the winding core.

[0028] A bending strip 303 is provided at the edge of the negative current collector 3. A flanged groove 302 is provided at the bending strip 303 of the negative current collector 3. The bending strip 303 is rectangular and extends out of the negative current collector 3. After being folded, the bending strip 303 contacts the end face of the negative current collector 3.

[0029] A lower plastic 4 is connected to the upper side of the negative current collector 3, and a base plate aluminum sheet 7 is connected to the upper side of the lower plastic 4. The lower plastic 4 has a shape similar to a single-pass shell, but its diameter is slightly smaller than that of the shell. It has a boss on the top and a chamfer that is different from the other three, which is used to distinguish the positioning. The lower plastic 4 is slightly larger than the negative current collector 3, which facilitates the connection between the negative current collector 3 and the lower plastic 4.

[0030] The upper end face of the lower plastic 4 is provided with a first boss 401. During assembly, the first boss 401 abuts against the lower end face of the substrate aluminum sheet 7.

[0031] The aluminum substrate 7 has a shape similar to a single-pass housing. A step is provided on the outer edge of the lower surface for assembling the single-pass housing 2, which facilitates the snapping of the single-pass housing 2. At the same time, the lower end face of the basic aluminum substrate 7 is also provided with a boss, which abuts against the first boss 401 for easy assembly.

[0032] Furthermore, the negative electrode cover also includes a negative electrode post 6, which is cylindrical and is riveted to form an I-shape, thereby achieving the contact between the negative electrode covers.

[0033] The negative current collector 3 has a circular through hole 301 at its center, which allows the negative electrode post 6 to pass through.

[0034] The lower plastic 4 has an annular countersunk hole 402 at its center, and a sealing ring 5 is provided at the annular countersunk hole 402. The sealing ring 5 is an annular sealing ring, and the compression ratio is 25%~50%.

[0035] The aluminum substrate 7 also has a central circular hole at the boss. The central circular hole is a countersunk hole. When the negative electrode post 6 is installed, it passes through the negative current collector 3, the lower plastic 4, the sealing ring 5, and the aluminum substrate 7 in one go. The lower side of the negative electrode post 6 abuts against the lower end face of the negative current collector 3, and the sealing ring 5 and the negative electrode post 6 are engaged, thereby ensuring the assembly work.

[0036] The aluminum substrate 3 has a circular countersunk hole with an upper plastic 8 and a circular groove on its upper surface to match the riveting aluminum block; the riveting aluminum block 9 has a through hole in its center and a circular groove on its upper surface to match the riveting extension area of ​​the negative electrode post 6, thereby achieving the overall assembly effect of the negative electrode cover plate assembly.

[0037] When assembling the negative terminal 6, the core and the negative terminal 6 come into contact, thus ensuring the normal operation of the cylindrical battery.

[0038] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A cylindrical battery structure, characterized by: The device includes a single-pass housing (22) with a cross-section of three tangent circles. The single-pass housing (22) has an upward-opening battery cavity. The lower end face of the single-pass housing (22) has several cross-shaped recessed areas (202). The center of the lower end face of the single-pass housing (22) has an injection hole (203). The upper side of the single-pass housing (22) is connected to a negative electrode cover plate. The negative electrode cover plate includes a negative current collector (3). A substrate aluminum sheet (7) is connected to the negative current collector (3). The substrate aluminum sheet (7) and the single-pass housing (22) are snapped together.

2. The cylindrical battery structure of claim 1, wherein, A sealing aluminum sheet (1) is welded to the injection hole (203), and the surface of the sealing aluminum sheet (1) is marked.

3. The cylindrical battery structure of claim 1, wherein, A lower plastic sheet (4) is provided between the negative current collector (3) and the substrate aluminum sheet (7), and the diameter of the negative current collector (3) and the lower plastic sheet (4) is slightly smaller than that of the substrate aluminum sheet (7).

4. The cylindrical battery structure of claim 3, wherein, The negative collector (3) is provided with a bending strip (303), which folds over and abuts against the lower plastic (4).

5. The cylindrical battery structure of claim 4, wherein, The upper surface of the lower plastic (4) is provided with a boss (401), and the boss (401) abuts against the aluminum sheet of the substrate (7).

6. The cylindrical battery structure of claim 5, wherein, The negative electrode cover plate also includes a negative electrode post (6), the boss (401) is provided with an annular countersunk hole (402), a sealing ring (5) is connected inside the annular countersunk hole (402), and a through hole is provided in the center of the substrate aluminum sheet (7).

7. The cylindrical battery structure of claim 6, wherein, The negative current collector (3) has a circular through hole (301) in the center. The negative electrode post (6) passes through the circular through hole (301), the sealing ring (5) and the through hole of the substrate aluminum sheet (7) in sequence. The negative electrode post (6) and the negative electrode cover plate are riveted together.

8. The cylindrical battery structure of claim 6, wherein, The negative electrode post (6) is connected to the upper plastic (8) above the aluminum sheet (7) of the substrate.

9. The cylindrical battery structure of claim 8, wherein, The negative electrode post (6) is connected to a riveted aluminum block (9) above the upper plastic (8).

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