Battery cell with pressure relief structure

Abstract

The utility model discloses a battery cell with a pressure relief structure, which comprises a shell with an opening at one end and a cover plate, a roll core is arranged in the shell, two ends of the roll core are respectively connected with a positive collector plate and a negative collector plate, a pole is arranged on the negative collector plate, the pole penetrates to the outer side of the shell in an insulating manner, and a pressure relief structure is arranged on the shell. The two sides of the circumferential edge of the positive current collecting disc are connected with the shell and the cover plate respectively, pressure relief holes are formed in the cover plate and the positive current collecting disc, the positive current collecting disc is provided with an installation plate surrounding the pressure relief holes, a plastic sleeve is arranged on the outer side of the installation plate in an injection molding mode, an aluminum plastic film is further arranged between the cover plate and the pressure relief holes of the positive current collecting disc, and the cover plate is provided with a sealing cover. The aluminum plastic film is connected with the plastic sleeve in a hot melting mode. The utility model has the beneficial effects that the cover plate is combined with the plastic sleeve in an integral injection molding manner, and the aluminum plastic film is combined with the plastic mold in a hot melting manner, so that the sealing property is good, the stress influence is reduced by utilizing hot melting tension, and the blasting value is more stable.

Description

TECHNICAL FIELD

[0001] The utility model relates to a battery technical field, concretely relates to a battery cell with pressure relief structure. BACKGROUND

[0002] Cylindrical battery cell is favored by all manufacturers due to its good process stability, when the cylindrical battery cell appears overcharge, short circuit or thermal runaway, gas is generated in the cell, causing the internal pressure of the cell to rise, the cell to bulge, and even to explode. In order to prevent the battery from exploding when it is in thermal runaway, an explosion-proof valve is usually provided at the non-pole end of the cylindrical battery cell, when the internal pressure of the cell reaches the opening threshold of the explosion-proof valve, the explosion-proof valve bursts, and the gas is discharged, thereby avoiding the explosion of the cell due to excessive internal pressure.

[0003] The traditional cylindrical battery cell usually adopts a score type explosion-proof valve, that is, an explosion-proof score is provided, and when the internal pressure of the cell is too large, the explosion-proof valve can burst along the explosion-proof score. The score often needs to be adjusted in depth for multiple times, and the explosion is tested for multiple times, so the overall process is complex. At present, cylindrical battery cells with valve sheet type explosion-proof valve structure have appeared, but the valve sheet and the shell or cover plate are fixed by laser welding, and the thickness of the valve sheet is relatively thin, which is easy to cause pinholes in the welding process, resulting in liquid leakage of the cell and causing safety risks. The high heat generated during welding can affect the strength of the material, causing the explosion pressure to change. SUMMARY

[0004] The utility model discloses a battery cell with pressure relief structure, the pressure relief valve sheet does not need to be welded with the cover plate, the cover plate and the plastic sleeve are combined by integral injection molding, the aluminum plastic film is combined with the plastic sleeve by hot melting, the sealing property is good, the hot melting tension is utilized, the stress influence is reduced, and the burst value is more stable.

[0005] The utility model discloses a battery cell with pressure relief structure, the pressure relief valve sheet does not need to be welded with the cover plate, the cover plate and the plastic sleeve are combined by integral injection molding, the aluminum plastic film is combined with the plastic sleeve by hot melting, the sealing property is good, the hot melting tension is utilized, the stress influence is reduced, and the burst value is more stable.

[0006] In some embodiments, the axial section of the plastic sleeve is U-shaped.

[0007] In some embodiments, it further comprises an insulating assembly for realizing the insulation between the shell and the pole, the shell and the negative current collector plate.

[0008] In some embodiments, the insulation assembly comprises a sealing ring arranged between the pole and the shell and a lower insulation gasket arranged between the negative bus bar and the shell.

[0009] In some embodiments, a nut is further included, the pole penetrating to the outside of the shell is further provided with a thread, and the thread is used in cooperation with the nut.

[0010] In some embodiments, an upper insulation gasket is further arranged between the nut and the shell.

[0011] In some embodiments, the circumferential edge of the positive bus bar is a stepped edge.

[0012] In some embodiments, the plastic sleeve is made of PP material.

[0013] Compared with the prior art, the pressure relief valve plate and the cover plate of the utility model do not need to be welded, the cover plate and the plastic sleeve are combined through the integral injection molding mode, the aluminum plastic film is combined with the plastic sleeve through the hot melting mode, the sealing property is good, the hot melting tension is used to reduce the stress influence, the burst value is more stable, the hot melting temperature is lower than the welding temperature, and the influence of the hot melting connection process on the performance of the aluminum plastic film is small.

[0014] The utility model will be described in detail below in combination with the drawings and specific embodiments. DRAWINGS

[0015] Fig. 1 is the structural schematic diagram of the utility model.

[0016] Fig. 2 is the structural schematic diagram of the non-pole end of the utility model.

[0017] Among them, 1, shell, 2, roll core, 3, negative bus bar, 4, positive bus bar, 5, pole, 6, nut, 7, upper insulation gasket, 8, sealing ring, 9, lower insulation gasket, 10, cover plate, 11, aluminum plastic film, 12, plastic sleeve. PREFERRED EMBODIMENT

[0018] As Figs. 1-2As shown, an electric core provided with a pressure relief structure includes an open-ended shell 1 and a cover plate 10, the shell 1 is provided with a winding core 2, the two ends of the winding core 2 are respectively connected with a positive current collector plate 4 and a negative current collector plate 3, the negative current collector plate 3 is provided with a pole 5, the pole 5 is insulated and penetrates to the outside of the shell 1, the two sides of the circumferential edge of the positive current collector plate 4 are respectively connected with the shell 1 and the cover plate 10, the cover plate 10 and the positive current collector plate 4 are both provided with a pressure relief hole, the positive current collector plate 4 is provided with a mounting plate surrounding the pressure relief hole, preferably, the thickness of the mounting plate is less than the minimum thickness of the positive current collector plate 4, the outside of the mounting plate is injection molded with a plastic sleeve 12, an aluminum plastic film 11 is further provided between the cover plate 10 and the pressure relief hole of the positive current collector plate 4, the aluminum plastic film 11 is hot melt connected with the plastic sleeve 12, specifically, the heat sealing layer (i.e. PP layer) of the aluminum plastic film 11 is hot melt connected with the plastic sleeve 12. Different from the traditional notch and welded valve plate, the cover plate 10 and the plastic sleeve 12 are combined by integral injection molding, the aluminum plastic film 11 is combined with the plastic sleeve 12 by hot melt, when the internal pressure of the electric core increases, the aluminum plastic film 11 is expanded and stressed, and when the edge hot melt tension limit is reached, it is separated to release pressure, the hot melt tension is used to reduce the stress influence, and the burst value is more stable.

[0019] In some embodiments, the axial section of the plastic sleeve 12 is U-shaped, the plastic sleeve 12 wraps the mounting plate, and the plastic sleeve 12 and the cover plate 10 are integrally formed by injection molding, so that the plastic sleeve 12 and the cover plate 10 are firmly combined.

[0020] In some embodiments, an insulation assembly is further included, which is used to realize the insulation between the shell 1 and the pole 5 and the insulation between the shell 1 and the negative current collector plate 3.

[0021] In some embodiments, the insulation assembly includes a sealing ring 8 and a lower insulation gasket 9, the sealing ring 8 is arranged between the pole 5 and the shell 1, and the lower insulation gasket 9 is arranged between the negative current collector plate 3 and the shell 1.

[0022] A nut 6 is further included, the pole 5 penetrating to the outside of the shell 1 is further provided with a thread, the thread is used in cooperation with the nut 6, the shell 1 is clamped by the nut 6 and the pole 5 to realize the fixation between the pole 5 and the shell 1.

[0023] In some embodiments, an upper insulation gasket 7 is further arranged between the nut 6 and the shell 1, which is used to realize the insulation connection between the nut 6 and the shell 1.

[0024] In some embodiments, the circumferential edge of the positive current collector plate 4 is a stepped edge. The minimum diameter of the stepped edge matches the inner diameter of the shell 1, and the stepped edge is arranged to facilitate the limiting of the positive current collector plate 4 by the shell 1.

[0025] In some embodiments, the plastic sleeve 12 is made of PP material.

[0026] In the description of the utility model, need understanding is, the term "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" "internal", "external", "clockwise", "counterclockwise", "axial", "radial", "circumferential" such as the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawing, just for the convenience of describing the utility model and simplifying the description, and not indicate or imply that the device or element referred to must have a particular orientation, with a particular orientation configuration and operation, therefore can not be understood as the restriction of the utility model.

[0027] In the utility model, unless another explicit provision and limitation, the terms "mount", "connect", "connect", "fix" and so on should be broad understanding, for example, can be fixed connection, also can be detachable connection, or integrated;Can be mechanical connection, also can be electric connection or can communicate with each other;It can be directly connected, also can be indirectly connected through intermediate medium, can be the communication or interaction relationship of two elements inside two elements, unless another explicit limitation.For ordinary skilled in the art, the above-mentioned terms can be understood according to the specific meaning of the utility model in the specific situation.

[0028] In the utility model, the term "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are contained in at least one embodiment or example of the utility model.In the description of the above terms, the illustrative description is not necessarily for the same embodiment or example.And, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.In addition, the skilled in the art can combine and combine the different embodiments or examples described in the specification and the characteristics of different embodiments or examples without contradiction.

[0029] Although the above-mentioned embodiments have been shown and described, it can be understood that the above-mentioned embodiments are exemplary, and cannot be understood as the limitation of the utility model, the change, modification, replacement and modification of the above-mentioned embodiments by the ordinary skilled in the art are within the protection scope of the utility model.

Claims

1. An electrochemical cell provided with a pressure relief structure, characterized by: The application relates to a battery including a shell with an open end and a cover plate, a winding core is arranged in the shell, two ends of the winding core are respectively connected with a positive collecting plate and a negative collecting plate, a pole is arranged on the negative collecting plate, the pole is insulated and penetrates to the outside of the shell, the two sides of the circumferential edge of the positive collecting plate are respectively connected with the shell and the cover plate, the cover plate and the positive collecting plate are both provided with pressure relief holes, the positive collecting plate is provided with a mounting plate surrounding the pressure relief hole, a plastic sleeve is injection molded on the outside of the mounting plate, an aluminum plastic film is further arranged between the cover plate and the pressure relief hole of the positive collecting plate, and the aluminum plastic film is hot melt connected with the plastic sleeve.

2. The battery cell with pressure relief structure of claim 1, wherein: The axial section of the plastic sleeve is U-shaped.

3. The battery cell with pressure relief structure of claim 1, wherein: The application further includes an insulation assembly for realizing insulation between the shell and the pole and between the shell and the negative collecting plate.

4. The battery cell with pressure relief structure of claim 3, wherein: The insulation assembly includes a sealing ring arranged between the pole and the shell and a lower insulation gasket arranged between the negative collecting plate and the shell.

5. The battery cell with pressure relief structure of claim 1, wherein: The application further includes a nut, the pole penetrating to the outside of the shell is further provided with a thread, and the thread is used in cooperation with the nut.

6. The battery cell with pressure relief structure of claim 5, wherein: An upper insulation gasket is further arranged between the nut and the shell.

7. The battery cell with pressure relief structure of claim 1, wherein: The circumferential edge of the positive collecting plate is a stepped edge.

8. The battery cell with pressure relief structure of claim 1, wherein: The plastic sleeve is made of PP.

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