Liquid injection structure and battery cell

Abstract

The utility model relates to the technical field of battery cells, in particular to a liquid injection structure and a battery cell, the liquid injection structure comprises a shell, a liquid injection hole insert, a flexible gasket and a sealing hole cover, the shell is provided with a liquid injection hole part penetrating through the shell in the first direction, and the liquid injection hole part comprises an inner side end and an outer side end which are formed on the two sides of the shell in the first direction; the liquid injection hole insert is embedded in the liquid injection hole part, the liquid injection hole insert is arranged close to the inner side end, and the flexible gasket is arranged between the liquid injection hole insert and the liquid injection hole part. The liquid injection hole insert is provided with a liquid injection through hole penetrating through the liquid injection hole insert in the first direction, and the sealing hole cover covers the outer side end and is fixedly connected with the shell so as to block the liquid injection through hole. According to the liquid injection structure and the battery cell provided by the invention, the processing precision of the liquid injection through hole is improved, the processing difficulty of the liquid injection hole is reduced, and the probability of collision damage between the liquid injection hole insert and the shell in the battery cell assembling and using process is effectively reduced.

Description

Technical Field

[0001] The present application relates to the technical field of battery cells, and particularly to a liquid injection structure and a battery cell. Background Art

[0002] With the increasing maturity of lithium-ion battery technology, lithium-ion batteries, as power batteries, are widely used in electric vehicles and energy storage fields, and the requirements for the performance and safety of lithium-ion batteries are increasing day by day. A lithium battery cell is a core component for the safety and assembly of a battery pack, and its structural design is crucial for the safety of the battery cell.

[0003] Most of the current liquid injection holes in the battery cell housing adopt an integrated stamping structure, with complex molds and high requirements for molds and equipment during forming. Moreover, the punch of the stamping die is a consumable part. Wear during use is not easily detected. If the wear and deformation of the punch are not detected in time, it is very easy for the stamping structure of the liquid injection hole to appear phenomena such as hole burrs, misalignment, and dimensional tolerance, which may further lead to insufficient stamping roundness of the stamping structure or even loose sealing of the liquid injection hole. In addition, replacing the punch is difficult to repair, with high costs and a long cycle.

[0004] The current integrated stamping structure for sealing the liquid injection hole has high requirements for the dimensions of the stamping structure and the liquid injection hole, with high manufacturing difficulty and high rejection rates; and during the assembly process and the use process of the battery cell, the integrated stamping structure for sealing the liquid injection hole is very likely to collide and deform with the battery cell housing, resulting in loose sealing of the liquid injection hole and liquid leakage. Summary of the Utility Model

[0005] The purpose of the present application is to provide a liquid injection structure and a battery cell to solve to a certain extent the technical problems existing in the prior art, such as most of the current liquid injection holes in the battery cell housing adopt an integrated stamping structure, with complex molds and high requirements for molds and equipment during forming. Moreover, the punch of the stamping die is a consumable part. Wear during use is not easily detected. If the wear and deformation of the punch are not detected in time, it is very easy for the stamping structure of the liquid injection hole to appear phenomena such as hole burrs, misalignment, and dimensional tolerance, which may further lead to insufficient stamping roundness of the stamping structure or even loose sealing of the liquid injection hole. In addition, replacing the punch is difficult to repair, with high costs and a long cycle. And the current integrated stamping structure for sealing the liquid injection hole has high requirements for the appearance dimensions, with high manufacturing difficulty and high rejection rates; and during the assembly process and the use process of the battery cell, the integrated stamping structure for sealing the liquid injection hole is very likely to collide and deform with the battery cell housing, resulting in loose sealing of the liquid injection hole and liquid leakage.

[0006] According to a first aspect of the present application, a liquid injection structure is provided, which includes a housing, a liquid injection hole insert, a flexible gasket, and a sealing hole cover. The housing is provided with a liquid injection hole portion that penetrates the housing along a first direction. The liquid injection hole portion includes an inner end and an outer end formed on both sides of the housing in the first direction. The liquid injection hole insert is embedded in the liquid injection hole portion and is disposed near the inner end. The flexible gasket is disposed between the liquid injection hole insert and the liquid injection hole portion;

[0007] The liquid injection hole insert is provided with a liquid injection through hole that penetrates the liquid injection hole insert along the first direction. The sealing hole cover is covered on the outer end and is fixedly connected to the housing to block the liquid injection through hole.

[0008] Preferably, the liquid injection structure further includes a sealing rubber plug, and the sealing rubber plug is press-fitted in the liquid injection through hole.

[0009] Preferably, the liquid injection hole insert includes a clamping portion and a fitting portion that are sequentially arranged along the first direction. The outer diameter of the clamping portion is larger than the outer diameter of the fitting portion, so as to form a boss at the connection between the clamping portion and the fitting portion;

[0010] A clamping edge is provided near the inner end of the liquid injection hole portion, and the clamping edge is clamped with the boss.

[0011] Preferably, the liquid injection hole insert further includes a guiding portion, and the guiding portion is disposed at an end of the fitting portion away from the clamping portion;

[0012] In the first direction, the outer diameter of the guiding portion gradually decreases from the end connected to the fitting portion to the other end.

[0013] Preferably, the flexible gasket is disposed between the clamping edge and the boss.

[0014] Preferably, the liquid injection through hole includes a first portion and a second portion that are sequentially arranged along the first direction, and the second portion is in interference fit with the sealing rubber plug;

[0015] The first portion is disposed on a side of the second portion close to the outer end. In the first direction, in the direction from the outer end to the inner end, the aperture of the first portion gradually decreases.

[0016] Preferably, the sealing hole cover includes a sticking edge portion and a plugging cover portion. The sticking edge portion is arranged in a circle along the edge of the plugging cover portion, and the sealing hole cover is attached to the inner edge of the liquid injection hole portion through the sticking edge portion.

[0017] Preferably, the sealing hole cover further includes an abutting and supporting portion which connects the adhering edge portion and the plugging cover portion. The sealing hole cover abuts against the liquid injection hole insert via the abutting and supporting portion, and a buffer gap is formed between the plugging cover portion and the liquid injection hole insert.

[0018] And / or, when the sealing hole cover is arranged on the liquid injection hole portion, the outer surface of the sealing hole cover is aligned with the outer surface of the housing.

[0019] Preferably, the wall thickness of the liquid injection hole insert is greater than 0.5 mm.

[0020] According to a second aspect of the present application, a battery cell is provided, including the liquid injection structure described in any of the above technical solutions. Therefore, it has all the beneficial technical effects of this liquid injection structure and will not be elaborated herein.

[0021] Compared with the prior art, the beneficial effects of the present application are as follows:

[0022] In the liquid injection structure provided by the present application, a liquid injection hole insert is arranged in the liquid injection hole portion of the housing, and the liquid injection through hole is arranged in the liquid injection hole insert. In this way, the structure in which the housing and the liquid injection hole are integrally formed in the prior art is split into a liquid injection hole portion and a liquid injection hole insert that are detachably connected to each other. On the one hand, the size of the liquid injection hole portion is enlarged relative to the existing liquid injection hole, which is more convenient for the processing of the housing and reduces the processing difficulty of the housing. On the other hand, the separate arrangement of the liquid injection hole insert and the housing can improve the flexibility of the processing of the liquid injection through hole, improve the processing accuracy of the liquid injection through hole, and reduce the processing difficulty of the liquid injection hole. In addition, by arranging a flexible gasket between the liquid injection hole insert and the liquid injection hole portion, not only can the sealing performance between the liquid injection hole insert and the housing be improved, but also a buffer structure is established between the liquid injection hole insert and the housing, effectively avoiding the collision and damage between the liquid injection hole insert and the housing during the assembly and use of the battery cell.

[0023] In order to make the above objects, features, and advantages of the present application more obvious and understandable, the following specific preferred embodiments are given, and detailed descriptions are made in conjunction with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic cross-sectional view of the liquid injection structure provided by the embodiment of the present application;

[0026] Figure 2 For Figure 1 the enlarged structural schematic diagram of the liquid injection structure at A;

[0027] Figure 3 Another sectional structural schematic diagram of the liquid injection structure provided by the embodiment of the present application;

[0028] Figure 4 The axonometric structural schematic diagram of the liquid injection hole insert provided by the embodiment of the present application.

[0029] Reference numerals:

[0030] 1 - Liquid injection hole insert; 11 - Clamping part; 12 - Fitting part; 13 - Guiding part; 14 - Liquid injection through hole; 141 - First part; 142 - Second part; 2 - Sealing hole cover; 21 - Plugging part; 22 - Adhesive edge part; 23 - Abutting and supporting part; 3 - Flexible gasket; 4 - Sealing rubber plug; 5 - Cover plate.

[0031] F1 - First direction. Detailed implementation manners

[0032] The technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present application.

[0033] The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application.

[0034] All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0035] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present application. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0036] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0037] The following refers to Figures 1 to 4 Describe the liquid injection structure and the battery cell according to some embodiments of the present application.

[0038] See Figures 1 to 4 As shown, an embodiment of the first aspect of the present application provides a liquid injection structure, which includes a housing, a liquid injection hole insert 1, a flexible gasket 3, and a sealing hole cover 2. The housing is provided with a liquid injection hole portion that penetrates the housing along the first direction F1. The liquid injection hole portion includes an inner end and an outer end formed on both sides of the housing in the first direction F1. The liquid injection hole insert 1 is embedded in the liquid injection hole portion, and the liquid injection hole insert 1 is disposed near the inner end. The flexible gasket 3 is disposed between the liquid injection hole insert 1 and the liquid injection hole portion. The liquid injection hole insert 1 is provided with a liquid injection through hole 14 that penetrates the liquid injection hole insert 1 along the first direction F1. The sealing hole cover 2 is covered on the outer end and fixedly connected to the housing to block the liquid injection through hole 14.

[0039] According to the liquid injection structure provided by the above technical features, the liquid injection hole insert 1 is disposed in the liquid injection hole portion of the housing, and the liquid injection through hole 14 is disposed in the liquid injection hole insert 1. In this way, the structure in which the housing and the liquid injection hole are integrally formed in the prior art is split into a liquid injection hole portion and a liquid injection hole insert 1 that are detachably connected to each other. On the one hand, the size of the liquid injection hole portion is enlarged relative to the existing liquid injection hole, which is more convenient for the processing of the housing and reduces the processing difficulty of the housing; on the other hand, the separate setting of the liquid injection hole insert 1 and the housing can improve the flexibility of the processing of the liquid injection through hole 14, improve the processing accuracy of the liquid injection through hole 14, and reduce the processing difficulty of the liquid injection hole. In addition, by providing the flexible gasket 3 between the liquid injection hole insert 1 and the liquid injection hole portion, not only can the sealing performance between the liquid injection hole insert 1 and the housing be improved, but also a buffer structure is established between the liquid injection hole insert 1 and the housing, effectively reducing the probability of collision damage between the liquid injection hole insert 1 and the housing during the assembly and use of the battery cell.

[0040] Preferably, as Figure 1 and Figure 2 shown, the above liquid injection structure may further include a sealing rubber plug 4, and the sealing rubber plug 4 is press-fitted in the liquid injection through hole 14 to further prevent the electrolyte from leaking through the liquid injection through hole 14.

[0041] Optionally, the sealing rubber plug 4 may be a columnar rubber plug, a columnar silica gel plug or other elastic plug structures to ensure the sealing performance of the liquid injection through hole 14.

[0042] Correspondingly, as Figure 3 shown, the above-mentioned liquid injection through hole 14 may include a first part 141 and a second part 142 arranged in sequence along the first direction F1. The second part 142 is in interference fit with the above-mentioned sealing rubber plug 4.

[0043] Preferably, as Figure 3 shown, the first part 141 is arranged on the side of the second part 142 close to the outer end. In the first direction F1, in the direction pointing from the outer end to the inner end, the aperture of the first part 141 gradually decreases to facilitate the penetration of the sealing rubber plug 4 into the liquid injection through hole 14.

[0044] Preferably, as Figure 2 shown, when the above-mentioned sealing rubber plug 4 is arranged in the above-mentioned liquid injection through hole 14, the top surface of the above-mentioned sealing rubber plug 4 may be aligned with the top surface of the liquid injection hole insert 1 (i.e., the end face close to the outer end).

[0045] Preferably, as Figure 2 shown, when the above-mentioned sealing hole cover 2 is covered on the above-mentioned liquid injection hole part, a buffer gap is provided between the sealing hole cover 2 and the top surface of the liquid injection hole insert 1. In this way, on the one hand, a certain installation error space can be reserved for the sealing rubber plug 4; on the other hand, when the air pressure in the battery cell is too high and the sealing rubber plug 4 is ejected, this buffer space can accommodate the ejected part of the sealing rubber plug 4 within a certain range.

[0046] Preferably, as Figures 1 to 4 shown, the liquid injection hole insert 1 includes a clamping part 11 and a fitting part 12 arranged in sequence along the first direction F1. The outer diameter of the clamping part 11 is larger than the outer diameter of the fitting part 12 to form a boss at the connection between the clamping part 11 and the fitting part 12.

[0047] Correspondingly, as Figures 1 to 3 shown, a clamping edge is provided at the inner end of the above-mentioned liquid injection hole part, and this clamping edge is clamped with the boss to realize the positioning of the liquid injection hole insert 1 in the first direction F1.

[0048] Preferably, the wall thickness of the above-mentioned liquid injection hole insert 1 may be greater than 0.5 mm to ensure the support stability of the liquid injection hole insert 1 for the liquid injection hole part.

[0049] It should be noted that the wall thickness of the above-mentioned liquid injection hole insert 1 can be understood as half of the difference between the outer diameter at the maximum outer diameter of the above-mentioned liquid injection hole insert 1 (i.e., the outer diameter of the clamping part 11) and the inner diameter of the following second part 142.

[0050] Preferably, asFigures 1 to 3 As shown, the above-mentioned fitting portion 12 is fitted to the inner side wall of the above-mentioned clamping edge to ensure the sealing performance of the liquid injection hole portion.

[0051] Furthermore, as Figure 2 and Figure 3 shown, the above-mentioned flexible washer 3 can be disposed between the clamping edge and the boss to further improve the sealing performance of the liquid injection hole portion.

[0052] Optionally, the above-mentioned flexible washer 3 can be annular to facilitate the flexible washer 3 to be arranged around the liquid injection hole portion.

[0053] Optionally, the above-mentioned flexible washer 3 can be an elastic sealing washer such as a rubber washer or a silicone washer.

[0054] Preferably, as Figure 2 and Figure 3 shown, the liquid injection hole insert 1 can further include a guiding portion 13, and the guiding portion 13 is arranged at one end of the fitting portion 12 far from the clamping portion 11. In the first direction F1, the outer diameter of the guiding portion 13 gradually decreases from the end connected to the fitting portion 12 to the other end, so as to facilitate the liquid injection hole insert 1 to penetrate into the liquid injection hole portion.

[0055] In an embodiment, as Figure 1 and Figure 2 shown, preferably, the above-mentioned sealing hole cover 2 can include a sticking edge portion 22 and a plugging cover portion 21, the sticking edge portion 22 is arranged around the edge of the plugging cover portion 21, and the sealing hole cover 2 is fitted to the inner edge of the liquid injection hole portion through the sticking edge portion 22 to ensure the sealing performance of the sealing hole cover 2 for plugging the liquid injection hole portion.

[0056] Preferably, as Figures 1 to 3 shown, the portion of the above-mentioned liquid injection hole portion near the outer end is a tapered hole. Taking the orientation shown in the figure as an example, from the upper end to the lower end of the tapered hole, the aperture of the tapered hole gradually decreases.

[0057] Correspondingly, as Figure 1 and Figure 2 shown, the above-mentioned sticking edge portion 22 is fitted to the above-mentioned tapered hole to improve the sealing performance of the sealing hole cover 2 for plugging the liquid injection hole portion.

[0058] Preferably, the above-mentioned sealing hole plug can be fixedly welded to the above-mentioned housing through the sticking edge portion 22.

[0059] Preferably, as Figure 2 shown, the sealing hole cover 2 can further include an abutting and supporting portion 23, the abutting and supporting portion 23 connects the sticking edge portion 22 and the plugging cover portion 21, and the sealing hole cover 2 abuts against the liquid injection hole insert 1 through the abutting and supporting portion 23 to improve the setting stability of the sealing hole cover 2.

[0060] Optionally, a ring-shaped groove that is recessed downward relative to the upper surface is provided on the upper surface of the corresponding part of the sealing hole plug and the abutting support portion 23 to reduce the mass of the sealing hole plug.

[0061] Correspondingly, as Figure 2 shown, the support of the abutting support portion 23 enables the formation of the above-mentioned buffer gap between the plugging cover portion 21 and the liquid injection hole insert 1.

[0062] Preferably, the above-mentioned edge attachment portion 22, abutting support portion 23, and plugging cover portion 21 can be integrally formed by a stamping process.

[0063] Preferably, as Figure 1 and Figure 2 shown, when the sealing hole cover 2 is arranged in the liquid injection hole portion, the outer surface of the sealing hole cover 2 is aligned with the outer surface of the housing, so as to ensure the flatness of the outer surface of the housing and reduce the space occupied by the sealing hole cover 2.

[0064] An embodiment of the second aspect of the present application further provides an electric core, including the liquid injection structure described in any of the above embodiments. Therefore, it has all the beneficial technical effects of this liquid injection structure and will not be elaborated here.

[0065] Preferably, the above-mentioned housing may include a cover plate 5, the cover plate 5 is arranged at the end of the above-mentioned housing in the first direction F1, and the liquid injection hole portion may be arranged on the cover plate 5.

[0066] Preferably, not shown in the figure, the above-mentioned electric core may further include a pole column, and the pole column is arranged on the cover plate 5.

[0067] It should be noted that the above-mentioned cover plate 5, housing, and pole column are all existing structures in the field of electric cores and will not be elaborated here.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A liquid injection structure, characterized in that: The invention comprises a shell, a liquid injection hole insert, a flexible gasket and a sealing hole cover, wherein the shell is provided with a liquid injection hole portion penetrating the shell along a first direction, the liquid injection hole portion comprises an inner end and an outer end formed on both sides of the shell in the first direction, the liquid injection hole insert is embedded in the liquid injection hole portion, and the liquid injection hole insert is arranged close to the inner end, and the flexible gasket is arranged between the liquid injection hole insert and the liquid injection hole portion; The injection hole insert is provided with an injection through hole penetrating the injection hole insert along the first direction, and the sealing hole cover is provided at the outer end and fixedly connected to the shell to seal the injection through hole.

2. The liquid injection structure according to claim 1, characterized in that: The liquid injection structure also includes a sealing rubber plug, which is interference-fittedly arranged in the liquid injection through hole.

3. The liquid injection structure according to claim 2, characterized in that: The injection hole insert comprises a clamping portion and a fitting portion sequentially arranged along the first direction, wherein the outer diameter of the clamping portion is larger than the outer diameter of the fitting portion, so as to form a boss at the connection between the clamping portion and the fitting portion; A clamping edge is provided near the inner end of the liquid injection hole, and the clamping edge is clamped with the boss.

4. The liquid injection structure according to claim 3, characterized in that: The injection hole insert also includes a guide portion, which is arranged at an end of the fitting portion away from the clamping portion; In the first direction, the outer diameter of the guide portion gradually decreases from one end connected to the fitting portion to the other end.

5. The liquid injection structure according to claim 3, characterized in that: The flexible gasket is arranged between the clamping edge and the boss.

6. The liquid injection structure according to claim 5, characterized in that: The liquid injection through hole comprises a first part and a second part sequentially arranged along the first direction, and the second part is interference-fitted with the sealing rubber plug; The first part is arranged on one side of the second part close to the outer end, and in the first direction, in a direction from the outer end to the inner end, the aperture of the first part gradually decreases.

7. The liquid injection structure according to any one of claims 1 to 6, characterized in that: The sealing hole cover comprises a sticking edge portion and a plugging portion, wherein the sticking edge portion is arranged along the edge of the plugging portion, and the sealing hole cover is attached to the inner edge of the liquid injection hole portion via the sticking edge portion.

8. The liquid injection structure according to claim 7, characterized in that: The sealing hole cover also includes an abutting support portion, the abutting support portion connects the sticking edge portion and the plugging portion, the sealing hole cover abuts against the injection hole insert via the abutting support portion, and a buffer gap is formed between the plugging portion and the injection hole insert; And / or, when the sealing hole cover is disposed on the liquid injection hole portion, the outer surface of the sealing hole cover is aligned with the outer surface of the shell.

9. The liquid injection structure according to claim 2, characterized in that: The wall thickness of the injection hole insert is greater than 0.5 mm.

10. A battery cell, characterized in that: The invention comprises the liquid injection structure according to any one of claims 1 to 9.

Images