Explosion-proof steel shell battery

Abstract

The utility model relates to the field of steel shell batteries, and discloses an explosion-proof steel shell battery, the battery comprises a bottom shell, a cover plate assembly and an explosion-proof assembly, the bottom shell is provided with an opening end, and the cover plate assembly is used for blocking the opening end; an exhaust through hole is formed in the side wall of the bottom shell, and the explosion-proof assembly is used for blocking the exhaust through hole; the anti-explosion assembly comprises an anti-explosion piece and an annular connecting piece, the annular connecting piece is arranged around the anti-explosion piece, and the annular connecting piece is welded to the side wall of the bottom shell; according to the explosion-proof steel shell battery, the safety and the miniaturization level of the battery are effectively improved.

Description

Technical Field

[0001] The utility model relates to the field of steel shell batteries, in particular to an explosion-proof steel shell battery. Background Art

[0002] In the current field of lithium battery technology, improving safety performance has always been a core issue of research and innovation, especially in the pursuit of higher energy density and more compact design. Traditional safety measures, such as integrated explosion-proof valves on the battery cover or bottom plate, play a key role. It automatically opens and releases gas when abnormal internal pressure or temperature rise is detected, thereby preventing the potential risk of explosion caused by the accumulation of internal pressure in the battery.

[0003] However, with the rapid development of battery technology, new structural designs, especially the use of special materials such as stainless steel or composite materials for the shell, and the pursuit of thin and light, miniaturized battery structures, have brought unprecedented challenges to traditional safety designs. In these new structures, traditional explosion-proof valve designs may be difficult to apply directly due to space limitations, material compatibility or structural integration difficulties, making it no longer a feasible solution to directly set up explosion-proof valves on the cover or bottom plate. Utility Model Content

[0004] The purpose of the utility model is to overcome the deficiencies in the prior art and provide an explosion-proof battery.

[0005] The purpose of this utility model is achieved through the following technical solutions:

[0006] An explosion-proof steel shell battery, the battery comprising a bottom shell, a cover plate assembly and an explosion-proof assembly, the bottom shell is provided with an open end, the cover plate assembly is used to block the open end; the side wall of the bottom shell is provided with an exhaust through hole, the explosion-proof assembly is used to block the exhaust through hole;

[0007] The explosion-proof assembly comprises an explosion-proof plate and an annular connecting plate, wherein the annular connecting plate is arranged around the explosion-proof plate, and the annular connecting plate is welded to the side wall of the bottom shell.

[0008] In one embodiment, the explosion-proof disc is made of aluminum, and the annular connecting piece is made of steel.

[0009] In one embodiment, the explosion-proof disc has a thickness of 0.1 mm to 0.2 mm; the annular connecting piece has a thickness of 0.1 mm to 0.2 mm.

[0010] In one embodiment, the explosion-proof sheet is provided with an explosion-proof groove, and the explosion-proof groove is formed by stamping.

[0011] In one embodiment, the annular connecting piece is provided with a through hole, the explosion-proof piece is provided with a boss portion and a connecting portion, the boss portion passes through the through hole, and the connecting portion is sealed and welded to the annular connecting piece.

[0012] In one embodiment, the explosion-proof groove is arranged on the boss portion.

[0013] In one embodiment, the explosion-proof groove is a strip-shaped groove, and the strip-shaped groove is centrally arranged along the length direction of the boss portion.

[0014] In one embodiment, a groove is formed on the side wall of the bottom shell around the exhaust through hole, and the groove is used to limit the annular connecting piece.

[0015] In one embodiment, the explosion-proof component is an integral arc-shaped structure, and its curvature is consistent with the side wall of the bottom shell.

[0016] In one embodiment, the cover plate assembly includes a cover plate and a pole piece, the cover plate is insulated and connected to the pole piece, a raised pole column is provided on the pole piece, the cover plate is provided with a through hole, and the pole column is accommodated in the through hole.

[0017] Compared with the prior art, the utility model has at least the following advantages:

[0018] 1. Space optimization and miniaturization design: Moving the explosion-proof components from the traditional base plate or cover plate to the battery side wall significantly reduces the space required at the battery end, thereby increasing the cell capacity and the battery's energy density.

[0019] 2. Improved safety: By opening exhaust holes on the side wall and sealing them with explosion-proof plates and annular connecting plates, the explosion-proof components on the side wall can respond to abnormal conditions inside the battery more quickly than traditional batteries, effectively release excess gas, reduce internal pressure accumulation, and thus reduce the risk of explosion.

[0020] 3. Improve the flexibility of battery structure: The explosion-proof component design (annular connecting piece + explosion-proof piece) improves the flexibility of battery structure design, especially when using special materials as the shell. The explosion-proof component can flexibly select the materials of the annular connecting piece and the explosion-proof piece according to the different materials and shapes of the battery shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a schematic structural diagram of an explosion-proof steel shell battery according to one embodiment of the utility model;

[0023] Figure 2 This is a schematic diagram of the explosion structure of an explosion-proof steel shell battery according to one embodiment of the utility model;

[0024] Figure 3 This is a schematic structural diagram of an explosion-proof assembly according to one embodiment of the utility model;

[0025] Figure 4 It is a schematic structural diagram of a cover plate assembly according to one embodiment of the utility model.

[0026] The numbers in the figure are: 10, explosion-proof steel shell battery; 100, bottom shell; 110, exhaust through hole; 120, groove; 200, cover assembly; 210, cover; 211, through hole; 220, pole piece; 221, pole; 230, insulating pad; 300, explosion-proof assembly; 310, explosion-proof plate; 311, explosion-proof groove; 312, boss part; 313, connecting part; 320, annular connecting piece; 321, via; 400, battery cell. DETAILED DESCRIPTION

[0027] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to the relevant drawings. The drawings provide preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.

[0028] See also Figure 1 and Figure 2 , an explosion-proof steel shell battery (10), the battery comprising a bottom shell (100), a cover plate assembly (200) and an explosion-proof assembly (300), the bottom shell (100) being provided with an open end, the cover plate assembly (200) being used to block the open end; a venting through hole (110) being provided on a side wall of the bottom shell (100), the explosion-proof assembly (300) being used to block the venting through hole (110); the explosion-proof assembly (300) comprising an explosion-proof sheet (310) and an annular connecting sheet (320), the annular connecting sheet (320) being provided around the explosion-proof sheet (310), and the annular connecting sheet (320) being welded to the side wall of the bottom shell (100).

[0029] It should be noted that the bottom shell (100) in the present invention is the main body of the battery and is provided with an open end at one end thereof. The explosion-proof steel shell battery (10) also includes a battery cell (400), which is placed in the bottom shell (100) from the open end. The cover plate assembly (200) is designed to tightly seal the open end. The connection between the cover plate assembly (200) and the bottom shell (100) is usually achieved by welding, sealing ring extrusion sealing or other reliable sealing technologies to ensure good air tightness and stability. Unlike traditional batteries that design explosion-proof valves on the cover plate assembly (200) or the bottom plate, the present invention opens one or more exhaust holes (110) on the side wall of the bottom shell (100) to provide a release path when the internal pressure of the battery increases abnormally, thereby preventing the battery from expanding or even exploding due to the accumulation of internal pressure.

[0030] The explosion-proof assembly (300) is composed of an explosion-proof plate (310) and an annular connecting plate (320). The explosion-proof plate (310) is directly located at the exhaust hole (110) as a pressure sensitive element. When the internal pressure of the battery reaches a preset threshold, the explosion-proof plate (310) will rupture or deform, quickly open the exhaust channel, and release excess gas, thereby protecting the battery from overpressure damage. The annular connecting plate (320) is arranged around the explosion-proof plate (310), firstly to provide support and positioning for the explosion-proof plate (310) to ensure that the explosion-proof plate (310) accurately covers the exhaust hole (110); secondly, it is connected to the side wall of the bottom shell (100) by welding to form a solid and sealed structure. This connection method ensures that the exhaust hole (110) remains closed in the non-triggered state, maintaining the normal working environment of the battery.

[0031] The explosion-proof steel shell battery (10) provided by the utility model realizes effective utilization of limited space by arranging the explosion-proof component (300) on the side wall; at the same time, the instant response mechanism of the explosion-proof plate (310) and the side wall exhaust design provide the battery with faster and more effective overpressure protection, thereby enhancing the overall safety performance; further, the design of the explosion-proof component (300) takes into account compatibility with bottom shells (100) of different materials, as well as the requirements for easy production, processing and maintenance.

[0032] Furthermore, the explosion-proof disc (310) is made of aluminum, and the annular connecting piece (320) is made of steel.

[0033] In the utility model, the explosion-proof component (300) is designed as a combined structure of an explosion-proof disk (310) and an annular connecting disk (320), and is made of aluminum and steel respectively, thereby showing various technical characteristics and advantages:

[0034] 1. Cost-effectiveness: The explosion-proof disk (310) is made of aluminum. Compared with the traditional ultra-thin steel sheets (generally the thickness must be controlled within 0.1mm and the price is high), aluminum is not only softer in texture, which is conducive to timely rupture and release of gas under abnormal pressure, but also has relatively low raw material and processing costs. This helps to reduce the manufacturing cost of the entire battery and improve market competitiveness.

[0035] 2. Welding performance and sealing: The annular connecting piece (320) is made of the same steel as the bottom shell (100), ensuring the reliability of the welding between the two. The high strength and good weldability of the steel make the welding seal between the annular connecting piece (320) and the side wall of the bottom shell (100) more stable, effectively preventing leakage in daily use or non-emergency situations, and ensuring the long-term sealing and safety of the battery.

[0036] 3. Design flexibility and functional separation: The explosion-proof assembly (300) is divided into two parts to achieve an optimized functional distribution. The annular connecting piece (320) is responsible for providing structural support and ensuring welding sealing, while the explosion-proof disk (310) focuses on its core safety release function. This modular design improves the overall effectiveness of the system and also facilitates the adjustment of the material and thickness of the explosion-proof disk (310) according to different application requirements to achieve the best safety performance balance.

[0037] 4. Complementary use of material properties: By combining the physical properties of aluminum and steel, it not only ensures the efficient execution of the explosion-proof function (aluminum is easy to rupture and release), but also ensures the stability and durability of the overall structure (high strength of steel).

[0038] Furthermore, the thickness of the explosion-proof disc (310) is 0.1 mm to 0.2 mm; and the thickness of the annular connecting disc (320) is 0.1 to 0.2 mm.

[0039] It should be noted that the thickness range of the explosion-proof disc (310) ensures that the thinner aluminum material is used to ensure timely rupture under abnormal pressure and control costs without sacrificing safety; although the annular connecting piece (320) is also designed as a thin sheet, it is made of steel, and its thickness of 0.1mm to 0.2mm is sufficient to provide the necessary mechanical strength and structural stability, ensuring a firm welding with the side wall of the bottom shell (100), as well as a continuous sealing effect under long-term use and various working conditions. The high strength characteristics of steel play a key role here, making the connecting part (313) a solid link in the entire battery structure; this thickness range is feasible for modern manufacturing, and it will not be difficult to process due to being too thin, nor will it increase unnecessary weight and cost due to being too thick, which is convenient for large-scale production using existing production processes, thereby improving production efficiency and yield rate.

[0040] See also Figure 3 Furthermore, an explosion-proof groove (311) is provided on the explosion-proof plate (310), and the explosion-proof groove (311) is formed by stamping.

[0041] It should be noted that the explosion-proof groove (311) is a preset weak area that can guide the explosion-proof plate (310) to break precisely along a predetermined trajectory when the internal pressure of the battery rises abnormally, rather than breaking randomly. This ensures the efficiency and directionality of pressure release, reduces accidental damage to other structures of the battery, and improves the accuracy of safety control.

[0042] Conventional batteries use explosion-proof steel sheets and when preparing explosion-proof grooves (311), laser grooving technology is generally used. Although this process can achieve high precision and flexibility, it is also accompanied by significant costs and technical challenges, such as high processing costs. For mass-produced batteries, the unit cost of laser grooving is difficult to control, which is not conducive to cost optimization; for another example, the processing efficiency of laser grooving is low; for another example, heat is generated during the laser grooving process, which may cause local hardening or deformation of the material, affecting the performance and reliability of the explosion-proof sheet (310).

[0043] In contrast, the explosion-proof plate (310) of the utility model is made of aluminum, so the explosion-proof groove (311) can be prepared on the explosion-proof plate (310) by stamping technology. First, stamping is an efficient mass production method. Once the mold is developed, the subsequent unit production cost is much lower than laser grooving, which is particularly suitable for large-scale production and can significantly reduce production costs. Secondly, stamping is fast and can complete the processing of a large number of parts in a short time, which is suitable for quickly responding to market demand and improving production efficiency. Furthermore, stamping avoids the thermal effects caused by laser processing, maintains the original properties of the material, and ensures that the mechanical properties and rupture characteristics of the explosion-proof plate (310) meet the design requirements. Finally, stamping produces less waste and environmental pollution than laser processing, is more environmentally friendly, and is conducive to sustainable production.

[0044] See also Figure 2 and Figure 3 Furthermore, the annular connecting piece (320) is provided with a through hole (321), the explosion-proof piece (310) is provided with a boss portion (312) and a connecting portion (313), the boss portion (312) is penetrated by a through hole (211), and the connecting portion (313) is sealed and welded with the annular connecting piece (320).

[0045] It should be noted that the boss portion (312) is penetrated by the through hole (211) of the annular connecting piece (320), and the connecting portion (313) is welded and fixed to the annular connecting piece (320), so that the explosion-proof component (300) forms a stable mechanical connection structure, ensuring the stable positioning of the explosion-proof piece (310) under normal working conditions of the battery, preventing displacement caused by vibration or external force impact, and also strengthening the pressure resistance of the entire explosion-proof component (300), thereby improving the durability of the battery. At the same time, the sealed welding of the connecting portion (313) and the annular connecting piece (320) ensures that even when the internal pressure of the battery changes, the gas release path is limited to the rupture of the explosion-proof piece (310) and will not leak from the welding interface. Furthermore, through the matching design of the boss portion (312) and the through hole (211), the installation of the explosion-proof piece (310) is simpler and faster. During the assembly process, it is only necessary to align the boss portion (312) of the explosion-proof disc (310) with the through hole (211) of the annular connecting disc (320), insert the bulge, and complete the welding, thereby simplifying the production process, reducing the possibility of assembly errors, and improving production efficiency.

[0046] See also Figure 3 Furthermore, an explosion-proof notch (311) is provided on the boss portion (312).

[0047] It should be noted that by setting the explosion-proof groove (311) on the boss portion (312), the initial position and path of the battery rupture under abnormal pressure can be more accurately controlled, and the material integrity and strength of the connecting portion (313) are retained, which is crucial for maintaining the structural stability and load-bearing capacity of the explosion-proof plate (310) in an unactivated state, especially when the battery is subjected to external force impact.

[0048] Furthermore, the explosion-proof notch (311) can be arranged on the side of the boss portion (312) away from the bottom shell (100) or on the side close to the bottom shell (100). The optimization selection is performed according to the working environment and internal pressure characteristics of the battery. According to the internal structure layout of different batteries, the most suitable notch position can also reduce the impact on other key components of the battery when it ruptures, protect fragile components such as electrodes and diaphragms, and maintain the overall structural stability and long-term performance of the battery.

[0049] Furthermore, the explosion-proof groove (311) is a strip-shaped groove, and the strip-shaped groove is arranged in the middle along the length direction of the boss portion (312).

[0050] It should be noted that the strip-shaped notch is arranged in the middle along the length direction of the boss portion (312), ensuring that when the internal pressure of the battery increases abnormally, the rupture can be carried out quickly along a predetermined and concentrated path. This design helps to release the internal pressure more evenly and effectively, avoids the asymmetric accumulation of pressure inside the battery, reduces the local stress concentration when the battery ruptures, and reduces the risk of explosion. At the same time, compared with the complex multi-point or asymmetric notch design, the strip-shaped and centered notch is easier to realize in the production process, and can be stamped and formed using a standardized mold, thereby improving production efficiency. At the same time, the notch position, size and depth of each explosion-proof plate (310) are highly consistent, thereby enhancing the quality control of battery products and the consistency between batches.

[0051] See also Figure 2 Furthermore, a groove (120) is provided on the side wall of the bottom shell (100) around the exhaust hole (110), and the groove (120) is used to limit the annular connecting piece (320).

[0052] It should be noted that the design of the groove (120) provides a precise installation position for the annular connecting piece (320), ensuring the precise alignment and fixation between the annular connecting piece (320), the explosion-proof disc (310) and the bottom shell (100). This limiting mechanism simplifies the assembly process, avoids the tedious manual alignment, and improves production efficiency and assembly accuracy.

[0053] See also Figure 1 and 3 Furthermore, the explosion-proof assembly (300) is an integral arc-shaped structure, and its curvature is consistent with the side wall of the bottom shell (100).

[0054] It should be noted that the overall arc-shaped explosion-proof component (300) can fit closely to the side wall of the bottom shell (100), especially in batteries that pursue high energy density and miniaturized design, which reduces unnecessary space waste and provides more space for core components such as battery cells, thereby increasing battery capacity. At the same time, the arc of the explosion-proof component (300) is consistent with that of the side wall of the bottom shell (100), which means that the two can fit perfectly, and when fixed by welding or other methods, a more continuous and uniform force-bearing surface can be formed, thereby enhancing the strength and stability of the overall structure. Such a design can better resist external shocks and internal pressure fluctuations, and reduce stress concentration points caused by structural mismatch.

[0055] See also Figure 4 Furthermore, the cover plate assembly (200) includes a cover plate (210) and a pole piece (220), the cover plate (210) is insulated and connected to the pole piece (220), a protruding pole column (221) is provided on the pole piece (220), the cover plate (210) is provided with a through hole (211), and the pole column (221) is accommodated in the through hole (211).

[0056] It should be noted that the cover plate assembly (200) is covered on the open end of the bottom shell (100), and the cover plate (210) and the pole piece (220) are insulated and bonded by an insulating pad (230). During assembly, the battery cell (400) is placed in the bottom shell (100), and the pole ear at one end of the battery cell (400) is welded to the bottom shell (100), and the pole ear at the other end of the battery cell (400) is welded to the side of the pole piece (220) away from the pole column (221), and then liquid is injected. Finally, the side of the cover plate (210) close to the pole piece (220) is laser welded to the bottom shell (100) to complete the sealed assembly of the battery.

[0057] The cover plate assembly (200) of a conventional cylindrical steel shell battery is often relatively thick and heavy, and usually relies on a rolling groove to complete a sealed connection with the bottom shell (100). The conventional cap design in batteries of the same height specification is not only complex in structure, but also occupies a large space, which directly leads to a reduction in the volume capacity of the battery cell (400). In the explosion-proof battery of the utility model, firstly, the explosion-proof valve is arranged on the side wall of the battery to avoid the explosion-proof design occupying the height of the cap assembly. Secondly, the cap assembly has a simple structure and is connected to the bottom shell (100) by laser welding, which minimizes the space occupied by the cap assembly, thereby providing a larger capacity for the battery cell (400) and ultimately improving the battery capacity.

[0058] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. An explosion-proof steel shell battery, characterized in that: The battery comprises a bottom shell, a cover plate assembly and an explosion-proof assembly, wherein the bottom shell is provided with an open end, and the cover plate assembly is used to block the open end; a venting through hole is provided on the side wall of the bottom shell, and the explosion-proof assembly is used to block the venting through hole; The explosion-proof assembly comprises an explosion-proof plate and an annular connecting plate, wherein the annular connecting plate is arranged around the explosion-proof plate, and the annular connecting plate is welded to the side wall of the bottom shell.

2. The explosion-proof steel shell battery according to claim 1, characterized in that: The explosion-proof disc is made of aluminum, and the annular connecting piece is made of steel.

3. The explosion-proof steel shell battery according to claim 2, characterized in that: The thickness of the explosion-proof plate is 0.1 mm to 0.2 mm; the thickness of the annular connecting plate is 0.1 to 0.2 mm.

4. The explosion-proof steel shell battery according to claim 2, characterized in that: The explosion-proof sheet is provided with an explosion-proof groove, and the explosion-proof groove is formed by stamping.

5. The explosion-proof steel shell battery according to claim 4, characterized in that: The annular connecting piece is provided with a through hole, the explosion-proof piece is provided with a boss portion and a connecting portion, the boss portion is penetrated by the through hole, and the connecting portion is sealed and welded to the annular connecting piece.

6. The explosion-proof steel shell battery according to claim 5, characterized in that: The explosion-proof groove is arranged on the boss portion.

7. The explosion-proof steel shell battery according to claim 6, characterized in that: The explosion-proof groove is a strip-shaped groove, and the strip-shaped groove is centrally arranged along the length direction of the boss portion.

8. The explosion-proof steel shell battery according to claim 1, characterized in that: The side wall of the bottom shell is provided with a groove surrounding the exhaust through hole, and the groove is used to limit the annular connecting piece.

9. The explosion-proof steel shell battery according to claim 1, characterized in that: The explosion-proof component is an integral arc-shaped structure, and its curvature is consistent with the side wall of the bottom shell.

10. The explosion-proof steel shell battery according to claim 1, characterized in that: The cover plate assembly comprises a cover plate and a pole piece, wherein the cover plate is insulated and connected to the pole piece, a protruding pole column is arranged on the pole piece, a through hole is opened on the cover plate, and the pole column is accommodated in the through hole.

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