Non-pole terminal structure of cylindrical battery cell

Abstract

The utility model discloses a non-pole end structure of a cylindrical battery cell, the cylindrical battery cell comprises a shell with an opening at one end, a roll core is arranged in the shell, the non-pole end is positioned at the opening end of the shell, the non-pole end structure also comprises a current collecting disc and a pressure relief valve plate, the peripheral side of the current collecting disc is connected with the opening end of the shell, the inner side of the current collecting disc is connected with the roll core, and the pressure relief valve plate is arranged in the shell. A sinking table groove is formed in the outer side of the flow collecting disc, an air release hole penetrating through the flow collecting disc is formed in the sinking table groove, the pressure release valve plate is connected to the outer side of the air release hole in a sealed mode through nanometer injection molding, and an injection molding layer is arranged on the whole outer side face of the flow collecting disc in a nanometer injection molding mode. The pressure relief valve has the advantages that the pressure relief valve plate is adopted to replace an anti-explosion nick, the pressure relief valve plate and the shell are integrated through nanometer injection molding, the bonding strength is high, the sealing performance is good, and welding is not needed. The structure is simple, a cover plate does not need to be arranged, the space utilization rate of the battery cell is high, and the injection molding layer can replace an insulating patch to achieve an insulating effect.

Description

Technical Field

[0001] This utility model relates to the field of cylindrical battery technology, specifically to a non-terminal end structure of a cylindrical battery cell. Background Technology

[0002] Cylindrical battery cells are favored by major manufacturers due to their relatively stable manufacturing process. However, when a cylindrical battery cell experiences thermal runaway, such as overcharging, short circuits, or overheating, gas is generated inside, causing the internal pressure to rise, the cell to bulge, or even explode. To prevent explosions during thermal runaway, explosion-proof valves are typically installed at the non-terminal ends of cylindrical battery cells. When the internal gas pressure reaches the valve's opening threshold, the valve ruptures, releasing the gas and preventing an explosion due to excessive internal pressure.

[0003] Currently, cylindrical battery cells typically employ a grooved explosion-proof valve, meaning they are equipped with explosion-proof grooves. When the internal pressure of the cell becomes too high, it can explode along these grooves. Grooving often requires multiple adjustments to the groove depth and numerous explosion tests, making the overall process complex. Furthermore, this structure is susceptible to interference during cell assembly, creating safety hazards. For example, the single-cell battery disclosed in Chinese utility model patent CN221994586U has grooves placed within a connecting groove. The outer bottom wall of the connecting groove needs to be welded to the current collector. The grooved area is relatively weak, making it prone to pores and pinholes during welding, leading to leakage and posing a safety risk. The high heat generated during welding can also affect the material strength, causing changes in its explosion-proof pressure. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a non-terminal end structure for a cylindrical battery cell. It uses a pressure relief valve plate instead of explosion-proof markings, and integrates the pressure relief valve plate with the housing through nano-injection molding, resulting in high bonding strength, good sealing, and no need for welding. The structure is simple, requires no cover plate, has high cell space utilization, and the injection-molded layer can also replace insulating patches, providing insulation.

[0005] The purpose of this utility model is achieved through the following technical measures: a non-pole end structure of a cylindrical battery cell, the cylindrical battery cell including a shell with one open end, a wound core inside the shell, the non-pole end being located at the open end of the shell, and also including a current collector and a pressure relief valve plate, the periphery of the current collector plate being connected to the open end of the shell, the inner side of the current collector plate being connected to the wound core, the outer side of the current collector plate being provided with a recessed groove, the recessed groove being provided with a vent hole penetrating the current collector plate, the pressure relief valve plate being sealed to the outer side of the vent hole by nano-injection molding, and the entire outer surface of the current collector plate being nano-injection molded with an injection molding layer.

[0006] In some embodiments, the collector plate has a stepped edge on its periphery, and the stepped edge is connected to the open end of the housing.

[0007] In some embodiments, the outer side of the collector plate is further provided with a positioning groove surrounding the vent hole.

[0008] In some embodiments, the thickness of the injection-molded layer is 0.1-0.2 mm.

[0009] In some embodiments, the injection-molded layer is made of PET or PP material.

[0010] Compared with existing technologies, the advantages of this invention are as follows: This invention uses a pressure relief valve plate instead of explosion-proof grooves, and the pressure relief valve plate and the housing are integrated into one piece using nano-injection molding, resulting in high bonding strength, good sealing performance, and no need for welding. A current collector plate is used instead of a cover plate, eliminating the need for a cover plate, increasing the internal space of the battery cell, and improving the utilization rate of internal space. An injection-molded layer is provided on the entire outer surface of the current collector plate, which can also replace the insulating patch, providing an insulating effect.

[0011] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model.

[0013] Figure 2 This is a schematic diagram of the collector plate.

[0014] Figure 3 This is a structural diagram of the manifold, pressure relief valve plate, and injection molding layer.

[0015] The components are: 1. housing, 2. manifold, 3. pressure relief valve plate, 4. injection molding layer, 5. recessed groove, 6. step edge, and 7. positioning groove. Detailed Implementation

[0016] like Figures 1 to 3As shown, a non-terminal end structure of a cylindrical battery cell is disclosed. The cylindrical battery cell includes a housing 1 with one open end, a wound core inside the housing 1, and the non-terminal end located at the open end of the housing 1. It also includes a current collector 2 and a pressure relief valve 3. The periphery of the current collector 2 is welded to the open end of the housing 1. The inner side of the current collector 2 is welded to the wound core, and the outer side of the current collector 2 has a recessed groove 5. A vent hole penetrating the current collector 2 is provided in the recessed groove 5. The pressure relief valve 3 is sealed to the outside of the vent hole via nano-injection molding. The entire outer surface of the current collector 2 is nano-injection molded with an injection molding layer 4. This disclosure, through the recessed groove 5, positions the pressure relief valve 3 within the recessed groove 5, which not only protects the pressure relief valve 3 but also provides space for its explosion, facilitating its explosion towards the outside of the battery cell. The pressure relief valve 3 and the current collector 2 are integrated through nano-injection molding, resulting in high bonding strength and good sealing performance. The current collector 2 is used instead of the cover plate, and the injection molding layer 4 is set on the entire outer side of the current collector 2. There is no need to set the cover plate, which increases the internal space of the battery cell and improves the utilization rate of the internal space. The injection molding layer 4 can also replace the insulating patch and play an insulating role. After the battery cell is assembled, only the insulating patch needs to be attached to the circumferential side of the battery cell, reducing the use of the insulating patch.

[0017] In some embodiments, the collector plate 2 has a stepped edge 6 on its periphery, and the stepped edge 6 is connected to the open end of the housing 1. Specifically, the minimum diameter of the stepped edge 6 matches the inner diameter of the housing 1. The stepped edge 6 facilitates the housing 1 in limiting the position of the collector plate 2.

[0018] In some embodiments, the outer side of the manifold 2 is further provided with a positioning groove 7 surrounding the vent hole. The positioning groove 7 is used to limit the pressure relief valve plate 3. During nano-injection molding of the manifold 2 and the pressure relief valve plate 3, the positioning groove 7 can limit the pressure relief valve plate 3, facilitating subsequent nano-injection molding operations.

[0019] In some embodiments, the thickness of the injection-molded layer 4 is 0.1-0.2 mm.

[0020] In some embodiments, the injection-molded layer 4 is made of PET or PP material.

[0021] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0022] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," 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 connection that allows communication between them; 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, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0023] In this utility model, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this utility model. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0024] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A non-terminal end structure for a cylindrical battery cell, the cylindrical battery cell comprising a housing with one open end, a wound core disposed within the housing, the non-terminal end being located at the open end of the housing, characterized in that: It also includes a collector plate and a pressure relief valve. The periphery of the collector plate is connected to the open end of the housing, the inner side of the collector plate is connected to the core, the outer side of the collector plate is provided with a recessed groove, the recessed groove is provided with a vent hole that penetrates the collector plate, the pressure relief valve is connected to the outer side of the vent hole by nano-injection molding, and the entire outer surface of the collector plate is nano-injection molded with an injection molding layer.

2. The cylindrical cell non-terminal end structure according to claim 1, characterized in that: The collector plate has a stepped edge on its periphery, and the stepped edge is connected to the open end of the housing.

3. The cylindrical cell non-terminal end structure according to claim 1, characterized in that: The outer side of the collector plate is also provided with a positioning groove surrounding the vent hole.

4. The non-terminal end structure of the cylindrical battery cell according to claim 1, characterized in that: The thickness of the injection-molded layer is 0.1-0.2 mm.

5. The non-terminal end structure of the cylindrical battery cell according to claim 1, characterized in that: The injection-molded layer is made of PET or PP material.

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