A cylindrical battery structure for high rate applications

Abstract

The utility model discloses a kind of high rate application cylindrical battery structure, it is related to cylindrical battery relevant technical field, including the shell of double pass, the both ends of the shell are connected with upper cover plate assembly and lower cover plate, the upper cover plate assembly includes pole, the pole is connected with current collector disc by laser welding, the pole and the upper cover plate assembly are connected by riveting;The lower cover plate is connected with the shell by penetration welding;The battery structure upper and lower cover plate and battery roll core are all rigid connection, different from present integrated bending structure, battery internal connecting structure is compact, rigid connection does not occur structural member abrasion with external vibration etc application scene, improve battery shock resistance and long-term reliability, further expand battery application scene.

Description

Technical Field

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

[0002] The existing cover plate assembly mainly consists of 1. pole post, 2. top cover plate, 3. sealing ring, 4. busbar, 5. lower plastic, 6. upper plastic, and 7. terminal.

[0003] The main existing technical features are: 1. The busbar and terminal post are integrated using traditional riveting technology, resulting in a long current transmission distance from the core through the busbar to the external terminal. 2. To facilitate bending and improve weldability, the busbar is kept thin and narrow. 3. The positive and negative terminals generally have similar structures, requiring multiple bending and positioning during cell assembly, making the process cumbersome. 4. Bending the positive and negative terminals will occupy a certain amount of height space in the cylindrical shell. Utility Model Content

[0004] Purpose of the invention: The purpose of this utility model is to provide a cylindrical battery structure for high-rate applications, which solves the problem that existing conventional cylindrical structural components have high internal resistance and cannot be used in high-rate application scenarios.

[0005] Technical solution:

[0006] A high-rate cylindrical battery structure, characterized in that: it includes a dual-channel housing, with an upper cover assembly and a lower cover plate respectively connected to both ends of the housing; the upper cover assembly includes an electrode post, the electrode post being connected to a current collector via laser welding; the electrode post and the upper cover assembly are connected by riveting; the lower cover plate is connected to the housing via through welding.

[0007] Preferably, the upper cover assembly includes an upper plastic, an upper aluminum plate, a sealing ring, and a lower plastic arranged in sequence, and the pole is connected to the upper plastic, the upper aluminum plate, the sealing ring, and the lower plastic.

[0008] Preferably, the upper aluminum cover plate is provided with a liquid injection hole, and a sealing nail is welded to the liquid injection hole.

[0009] Preferably, the lower plastic is provided with a plurality of circular holes, and the circular holes correspond to the injection holes.

[0010] Preferably, the lower plastic is provided with a plurality of protrusions, which abut against the manifold.

[0011] Preferably, an explosion-proof valve and an explosion-proof valve protection patch are respectively provided on both ends of the upper aluminum cover plate, and the explosion-proof valve protection patch is located on the side of the upper aluminum cover plate closer to the housing.

[0012] Preferably, the lower cover plate is provided with a corresponding explosion-proof valve.

[0013] Preferably, the collector plate has a flange, and the flange is fixedly connected to the pole post.

[0014] Preferably, the collector plate has several through holes on the periphery of the flange.

[0015] Beneficial effects: The upper and lower cover plates of the battery structure are rigidly connected to the battery core. Unlike the existing integrated bending structure, the internal connection structure of the battery is compact. The rigid connection will not cause structural wear due to external vibration and other application scenarios, which improves the battery's shock resistance and long-term reliability, and further expands the battery's application scenarios. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall exploded structure of this utility model;

[0017] Figure 2 This is a top view of the upper cover plate of this utility model.

[0018] Figure 3 This is a schematic diagram of the collector plate structure of this utility model;

[0019] Figure 4 This is a schematic diagram of the pole structure of this utility model.

[0020] Reference numerals: 12. Housing; 13. Lower cover plate; 14. Pole post; 15. Manifold; 16. Upper aluminum cover plate; 17. Sealing ring; 18. Lower plastic; 19. Upper plastic; 21. Injection hole; 22. Explosion-proof hole; 23. Explosion-proof valve protective patch; 24. Explosion-proof valve; 25. Flanged edge; 26. Round hole; 27. Sealing nail; 28. Aluminum ring. Detailed Implementation

[0021] 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.

[0022] Example 1

[0023] like Figure 1 As shown, a low-cost, high-rate cylindrical battery structure is provided, comprising an upper cover plate, a housing 12, and a lower cover plate 13.

[0024] The housing 12 is a double-pass aluminum or steel housing. The double-pass design improves assembly flexibility and reduces overall processing costs compared to a single-pass housing with a bottom explosion-proof integrated molding structure.

[0025] The housing 12 is used to house the battery cells. The lower cover plate 13 is connected to the battery cells. The lower cover plate 13 is directly connected to the core and housing through bottom penetration welding, eliminating the need for the lower collector plate structure.

[0026] like Figure 4 As shown, the upper cover plate further includes a pole post 14, and a collector plate 15 is connected to the side of the upper cover plate near the housing 12. The pole post 14 is further welded to the collector plate 15 by laser, which eliminates the conventional collector plate connection part and bending assembly process, and simultaneously reduces material costs and manufacturing costs.

[0027] The upper cover plate, the housing 12, and the lower cover plate 13 are directly connected. The upper cover plate and the lower cover plate 13 are rigidly connected to the battery core. Unlike the existing integrated bending structure, the internal connection structure of the battery is compact. The rigid connection will not cause structural wear due to external vibration and other application scenarios, which improves the battery's shock resistance and long-term reliability, further expanding the battery's application scenarios. The battery structure is efficient and simple, making full use of the internal space of the cylindrical housing, minimizing the current path length, reducing energy loss, and lowering costs while improving battery energy density, rate performance, and safety performance.

[0028] like Figure 2 As shown, the upper cover plate includes an aluminum ring 28, an upper plastic plate 19, an upper cover aluminum sheet 16, a sealing ring 17, a lower plastic plate 18, and a collector plate 15, designed sequentially. The upper plastic plate 19, the upper cover aluminum sheet 16, the sealing ring 17, and the lower plastic plate 18 are all provided with through holes in the center. The pole post 14 passes through the through hole in the center. Unlike the traditional press riveting process, the upper plastic plate 19, the upper cover aluminum sheet 16, the sealing ring 17, and the lower plastic plate 19 are tightly connected by the pole post 14 riveting process. This riveting process solves the problem that the traditional press riveting cannot tightly fit large diameter (≥4mm) pole posts, and broadens the application scenarios of high current carrying capacity.

[0029] Furthermore, the upper cover aluminum sheet 16 integrates explosion-proof and liquid injection functions, and the upper cover aluminum sheet 16 is provided with a through liquid injection hole 21 and an explosion-proof hole 22.

[0030] A sealing pin 27 is installed at the injection hole 21. After the injection is completed, the sealing pin 27 is welded to the aluminum sheet 16 of the upper cover, and the sealing pin 27 seals the injection hole 21.

[0031] An explosion-proof valve protection patch 23 and an explosion-proof valve 24 are installed on the explosion-proof hole 22 on the upper cover aluminum sheet 16. The explosion-proof valve 24 is located between the explosion-proof protection patch 23 and the explosion-proof hole 22. The explosion-proof valve 24 on the upper cover aluminum sheet 16, together with the explosion-proof valve or explosion-proof marking line in the center of the lower cover plate 13, the dual explosion-proof valve design of the battery cell and the thermal separation function will greatly improve the safety and reliability of the battery cell in the thermal runaway system.

[0032] like Figure 3As shown, the collector plate 15 further includes a flange 25 in the middle area, and a number of circular holes 26 are provided on the periphery of the flange 25. In this embodiment, there are four circular holes 26 arranged in an array. The flange 25 and the surrounding circular holes 26 can be integrally stamped and assembled with the lower surface of the electrode post 14 through the flange 25. The collector plate 15 is connected to the upper cover plate by splicing or through laser welding. The four symmetrically distributed hole structures are conducive to electrolyte wetting and gas discharge.

[0033] The upper plastic 19 insulating parts are designed with right angles, which helps to increase the amount of plastic injected and the yield of the injection molding process.

[0034] The lower plastic insulating component 18 has a porous and raised structure. The round hole structure facilitates the injection and wetting of electrolyte, and the four symmetrically distributed raised structures press the current collector 15, which serves to stop movement and increase heat dissipation.

[0035] Example 2: High-rate fast-charging battery for drones

[0036] Battery structure:

[0037] Housing: Double-through aluminum alloy housing, wall thickness 0.6mm, surface anodized treatment; upper cover plate: the pole adopts a copper-plated nickel riveting structure with a diameter of 10mm, and is laser-penetrated welded to a 0.5mm thick nickel manifold (welding point diameter 1.2mm×4 symmetrically distributed); lower cover plate: 2.0mm thick 3-series aluminum plate, with explosion-proof cross lines engraved in the center (bursting pressure 0.8MPa); insulation parts: upper plastic (2) right-angle injection molded part (draft angle 1.5°), lower plastic (8) with 4 PP material protrusions with a height of 0.5mm.

[0038] Cell performance data:

[0039] During continuous discharge at 20C, the temperature rise of the electrode post is ≤15℃ (≥25℃ for traditional structures); after 500 cycles of 5-minute fast charging (6C), the internal resistance increases by <5%; and there is no electrolyte leakage after a drop test (1.5m height).

[0040] Example 3: High-power battery for power tools

[0041] Battery structure:

[0042] Housing: Double-pass nickel-plated steel housing with a 5μm insulating layer on the inner wall; Top cover: Explosion-proof valve integrated with injection hole (hole diameter 1.0mm), sealing nails are laser-welded; Manifold: 0.2mm thick copper-aluminum composite plate, flange height 1.0mm (increasing the contact area with the pole by 65%); Bottom cover: 3.0mm thick aluminum alloy, fiber laser circumferentially welded to the housing (weld width 0.8mm).

[0043] Battery performance data:

[0044] When continuously discharged at 50A, the voltage drop is <1.4V (compared to >1.6V for traditional structures); after 1000 charge-discharge cycles under actual vibration conditions, there are no cracks at the weld of the current collector (the crack rate of traditional bending structures is >30%); the explosion-proof valve opens synchronously in both directions at 150℃, and the thermal runaway delay is ≥5 minutes.

[0045] Example 4: High-cycle battery for automotive start-stop systems

[0046] Battery structure:

[0047] Housing: Double-walled nickel-plated steel housing, 0.8mm thick, with sandblasted inner wall (Ra 1.2μm) to enhance electrolyte wettability; Top cover: The electrode post uses 6mm diameter copper-aluminum composite rivets, which are then laser-welded to a 0.4mm thick copper manifold (weld length 15mm); Explosion-proof valve pressure threshold 1.2MPa; Bottom cover: 2.5mm thick 304 stainless steel, with a center-stamped explosion-proof cross-shaped line (rupture pressure 1.5MPa); Insulation components: The lower plastic is made of PPS material, with a raised structure embedding a thermally conductive silicone pad (thermal conductivity 1.5W / mK).

[0048] Battery performance data:

[0049] High rate performance: Voltage maintenance ≥9.6V during 30C pulse discharge (2s) at room temperature (conventional lead-acid battery ≤8.4V);

[0050] -30℃ low temperature starting current ≥800A (only 500A for lead-acid batteries of the same volume); cycle life: 25~75% SOC shallow cycle life ≥20,000 cycles (capacity decay <20%); after vibration test (GB / T 31467.3), the pole torque remains ≥5N·m (initial value 5.5N·m); safety features: dual explosion-proof valves open synchronously during short circuit, shell surface temperature ≤120℃ (traditional single explosion-proof valve structure ≥180℃); explosion-proof markings on the lower cover plate for directional pressure relief, and electrolyte spray angle controlled within a 60° cone angle.

[0051] 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 for high-rate applications, characterized in that: The device includes a dual-port housing, with an upper cover plate assembly and a lower cover plate connected to its two ends respectively. The upper cover plate assembly includes a pole post, which is connected to a current collector plate by laser welding. The pole post and the upper cover plate assembly are connected by riveting. The lower cover plate is connected to the housing by through welding.

2. The cylindrical battery structure for high-rate applications according to claim 1, characterized in that, The upper cover assembly includes an upper plastic, an upper aluminum plate, a sealing ring, and a lower plastic arranged in sequence, and the pole is connected to the upper plastic, the upper aluminum plate, the sealing ring, and the lower plastic.

3. The cylindrical battery structure for high-rate applications according to claim 2, characterized in that, The upper aluminum plate is provided with a liquid injection hole, and a sealing nail is welded to the liquid injection hole.

4. The cylindrical battery structure for high-rate applications according to claim 3, characterized in that, The lower plastic has several round holes, and the round holes correspond to the injection holes.

5. A cylindrical battery structure for high-rate applications according to claim 4, characterized in that, The lower plastic has several protrusions, which abut against the manifold.

6. The cylindrical battery structure for high-rate applications according to claim 2, characterized in that, An explosion-proof valve and an explosion-proof valve protection patch are respectively provided on both ends of the upper cover aluminum plate, and the explosion-proof valve protection patch is located on the side of the upper cover aluminum plate closer to the housing.

7. A cylindrical battery structure for high-rate applications according to claim 6, characterized in that, The lower cover plate is equipped with a corresponding explosion-proof valve.

8. The cylindrical battery structure for high-rate applications according to claim 1, characterized in that, The collector plate has a flange, and the flange is fixedly connected to the pole post.

9. A cylindrical battery structure for high-rate applications according to claim 8, characterized in that, The collector plate has several through holes on the periphery of the flange.

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