Sealing assembly for sealing battery cell liquid injection hole
By using shape memory metal components in sealed components in lithium-ion batteries to achieve shape changes at different temperatures, the problem of electrolyte replenishment caused by welding and encapsulation is solved, ensuring stable cell performance and supporting battery recycling and research.
Patent Information
- Application Number
- CN202520404039.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-10
- Publication Date
- 2026-02-13
- Estimated Expiration
- 2035-03-10
AI Technical Summary
The current welding and packaging method of lithium-ion batteries makes it impossible to replace and replenish the electrolyte inside the cell in a timely manner. As a result, the cell performance deteriorates as the electrolyte is consumed, and the aged cells cannot be tested further, which limits the recycling and research value of the batteries.
A sealing assembly is adopted, including a seal and a shape memory metal component. The shape change of the shape memory metal component under heating and cooling conditions is used to achieve a detachable seal for the electrolyte injection hole of the battery cell. The shape memory effect of the shape memory metal component enables the detachable seal of the sealing assembly under different conditions.
It achieves a detachable seal for the electrolyte injection hole of the battery cell, solves the problem of the electrolyte not being able to be replaced in a timely manner, maintains stable battery cell performance, and supports the recycling of batteries and the study of aging mechanisms.
Smart Images
Figure CN223911836U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to a battery technical field especially relates to a kind of sealing assembly for sealing liquid injection hole of battery cell. BACKGROUND
[0002] With the increasingly serious global climate change and environmental problems, energy storage batteries, especially lithium-ion batteries, have received widespread attention due to their widespread application in new energy storage and electric vehicles. To further study the performance of lithium-ion batteries and improve their efficiency, researchers have developed new testing methods and improved materials and structures to enhance battery performance to meet market and consumer demand.
[0003] Currently, the packaging of lithium-ion batteries mainly uses welding technology to seal the battery case. Although this method ensures the sealing of the battery to some extent, it also brings a series of problems. As the battery is used, the electrolyte is continuously consumed, leading to a decrease in battery performance. Due to the limitations of welding packaging, the electrolyte inside the battery cannot be replaced and supplemented in time, leading to a decrease in battery performance as the electrolyte is consumed. In addition, due to the welding packaging of the battery, the aged battery can only collect electrolyte through disassembly, leading to the inability to continue testing the disassembled battery, limiting the in-depth study of the aging mechanism of the battery. The battery with welded packaging cannot continue to charge and discharge after the electrolyte is taken out, not only limiting the recycling and testing of the battery, but also reducing the service life and research value of the battery. SUMMARY
[0004] The utility model aims at providing a kind of sealing assembly for sealing liquid injection hole of battery cell, solve the problem that the electrolyte inside the battery cannot be replaced and supplemented in time due to the welding packaging of existing battery, leading to a decrease in battery performance as the electrolyte is consumed.
[0005] To achieve the above-mentioned purpose, the utility model provides a kind of sealing assembly for sealing liquid injection hole of battery cell, the sealing assembly includes sealing piece and memory metal piece;
[0006] The sealing piece cooperates with the liquid injection hole of the battery cell to achieve sealing;
[0007] The memory metal piece has a heating state and a cooling state during application;
[0008] When the memory metal piece is in the heating state, one end of the memory metal piece can penetrate the sealing piece and extend to the outside of the liquid injection hole, and the other end is clamped and limited to the sealing piece;
[0009] When the memory metal piece is in the cooling state, one end of the memory metal piece that extends to the outside of the liquid injection hole is deformed to fit the inner surface of the battery cell cover plate.
[0010] Further, in the sealing assembly, the memory metal piece comprises a clamping portion; the clamping portion has a wedge-shaped structure, and the outer diameter of the wedge-shaped structure decreases along the insertion direction, and the wedge-shaped structure is clamped with the sealing piece.
[0011] Further, in the sealing assembly, one end of the clamping portion away from the wedge-shaped structure is interference-fitted with the sealing piece.
[0012] Further, in the sealing assembly, the memory metal piece further comprises a deformation portion arranged at one end of the clamping portion.
[0013] When the memory metal piece is in a heated state, the deformation portion is parallel to the insertion direction of the clamping portion.
[0014] When the memory metal piece is in a cooled state, the deformation portion is perpendicular to the insertion direction of the clamping portion.
[0015] Further, in the sealing assembly, a plurality of deformation portions are arranged in a ring shape at equal intervals.
[0016] Further, in the sealing assembly, the deformation portion is arranged in a strip-shaped structure.
[0017] Further, in the sealing assembly, a gap is reserved between two adjacent deformation portions, and the deformation portion is switched between the heated state and the cooled state.
[0018] Further, in the sealing assembly, the sealing piece comprises a first sealing portion and a second sealing portion, and the memory metal piece penetrates the first sealing portion and the second sealing portion in sequence.
[0019] Further, in the sealing assembly, the first sealing portion has a wedge-shaped penetration hole, and the memory metal piece can penetrate the wedge-shaped penetration hole of the first sealing portion to clamp the first sealing portion; the second sealing portion has a cylindrical penetration hole, and the memory metal piece can penetrate the cylindrical penetration hole to interference-fittedly clamp the second sealing portion.
[0020] Further, in the sealing assembly, the sealing piece is made of a material having elasticity and chemical resistance.
[0021] Compared with the prior art, the utility model has at least the following beneficial effects:
[0022] The utility model provides a sealing assembly for sealing liquid injection hole of electric core, through the shape memory effect of memory metal piece, the shape change under two different states of heating and cooling, realize the detachable sealing of sealing assembly to liquid injection hole, thereby solve the problem that the electrolyte of existing electric core adopting welding package cannot be replaced and supplemented in time, leading to the performance of electric core descending along with the consumption of electrolyte. BRIEF DESCRIPTION OF DRAWINGS
[0023] Figure 1 It is the section detail view of the memory metal piece in the sealing assembly of the utility model one embodiment installing on the liquid injection hole of electric core cover plate in heating state;
[0024] Figure 2 It is the section detail view of the memory metal piece in the sealing assembly of the utility model one embodiment installing on the liquid injection hole of electric core cover plate in cooling state;
[0025] Figure 3 It is the plan view of the sealing assembly of the utility model one embodiment;
[0026] Figure 4 It is the three-dimensional structure schematic diagram of the memory metal piece in the sealing assembly of the utility model one embodiment in heating state;
[0027] Figure 5 It is the section view of the memory metal piece in the sealing assembly of the utility model one embodiment in heating state;
[0028] Figure 6 It is the three-dimensional structure schematic diagram of the memory metal piece in the sealing assembly of the utility model one embodiment in cooling state;
[0029] Figure 7 It is the section view of the memory metal piece in the sealing assembly of the utility model one embodiment in cooling state;
[0030] Figure 8 It is the front view of the memory metal piece in the sealing assembly of the utility model one embodiment;
[0031] Figure 9 It is the plan view of the memory metal piece in the sealing assembly of the utility model one embodiment;
[0032] Figure 10 It is the section view of the liquid injection hole of electric core cover plate of the utility model one embodiment;
[0033] Figure 11 It is the plan view of the sealing assembly of the utility model one embodiment installing on the electric core cover plate;
[0034] Figure 12The sectional view of the sealing assembly in the heating state of the memory metal piece installed on the electric core cover plate in an embodiment of the utility model;
[0035] Figure 13 The sectional view of the sealing assembly in the cooling state of the memory metal piece installed on the electric core cover plate in an embodiment of the utility model.
[0036] 1, sealing piece; 11, first sealing part; 12, second sealing part; 2, memory metal piece; 21, clamping part; 211, first clamping part; 212, second clamping part; 22, deformation part; 3, electric core cover plate; 31, liquid injection hole; 311, first notch; 312, second notch; 4, sealing assembly. DETAILED DESCRIPTION
[0037] The sealing assembly for sealing the liquid injection hole of the electric core of the utility model will be described in more detail below in conjunction with the schematic diagram, wherein the preferred embodiment of the utility model is indicated, and it should be understood that the utility model described herein can be modified by those skilled in the art, and the advantageous effects of the utility model can still be achieved. Therefore, the following description should be understood as extensive knowledge for those skilled in the art, and not as a limitation of the utility model.
[0038] In order to be clear, not all features of the actual embodiment are described. In the following description, well-known functions and structures are not described in detail, because they will make the utility model confused by unnecessary details. It should be considered that in the development of any actual embodiment, a large number of implementation details must be made to achieve the specific goals of the developers, such as changing from one embodiment to another according to the relevant system or relevant business restrictions. In addition, it should be considered that such development work may be complex and time-consuming, but it is only routine work for those skilled in the art.
[0039] The utility model is described in more detail in the following paragraphs with reference to the drawings. The advantages and features of the utility model will be clearer according to the following description. It should be noted that the drawings are very simplified and use non-precise proportions, only to facilitate, clear and assist the purpose of explaining the embodiment of the utility model.
[0040] As mentioned in the background, the current lithium ion battery is usually packaged by welding. This packaging method makes the electrolyte in the electric core unable to be replaced and supplemented in time, resulting in the performance of the electric core declining with the consumption of electrolyte. Moreover, due to the welding packaging of the electric core, the aged electric core can only collect electrolyte by disassembling, which leads to the disassembled battery being unable to continue testing, limiting the in-depth study of the battery aging mechanism.
[0041] As Figures 1-13As shown, the present embodiment provides a sealing assembly for sealing the liquid injection hole of the battery cell, which comprises a sealing member 1 and a memory metal member 2.
[0042] Specifically, in the present embodiment, the sealing member 1 is in interference fit with the liquid injection hole 31 of the battery cell, thereby ensuring that there is no gap between the sealing member 1 and the liquid injection hole 31, so as to prevent the leakage of electrolyte during the operation of the battery cell.
[0043] Further, the memory metal member 2 has a heating state and a cooling state during application. As shown in Figure 1 Figure 4 and Figure 5 , when the memory metal member 2 is in the heating state, one end of the memory metal member 2 can penetrate the sealing member 1 and extend to the outside of the liquid injection hole 31 along the insertion direction, and the other end is clamped and limited to the sealing member 1. When the memory metal member 2 is in the cooling state, the end of the memory metal member 2 extending to the outside of the liquid injection hole 31 is deformed to fit the inner surface of the battery cell cover plate 3, so as to keep the sealing assembly 4 in good sealing effect during the operation of the battery cell.
[0044] It should be noted that memory metal is widely used in various mechanical and electronic devices that require temperature response. Its unique shape memory effect enables it to change shape at different temperatures. In the present embodiment, the memory metal member can be made of nickel-titanium alloy (Ni-Ti alloy), which has excellent shape memory performance.
[0045] Specifically, the temperature of the memory metal member 2 in the heating state is higher than the temperature at which the memory metal member deforms. When the memory metal member 2 is heated to a predetermined phase transition temperature, it will recover from the initial shape to its memory shape; when the memory metal member 2 cools to a certain temperature, it deforms from the memory shape to the initial shape.
[0046] It should be noted that, in order to avoid the leakage of electrolyte due to poor sealing of the sealing assembly 4 during the operation of the battery cell, the working temperature of the sealing assembly 4 (i.e. the working temperature of the battery cell using the sealing assembly) should be less than the temperature at which the memory metal member 2 deforms (i.e. the temperature in the cooling state).
[0047] Further, as shown in Figure 9 , the memory metal member 2 comprises a clamping portion 21; the clamping portion 21 has a wedge-shaped structure, and the outer diameter of the wedge-shaped structure decreases along the insertion direction and clamps the sealing member 1. Specifically, the clamping portion 21 can be designed as a whole wedge shape, or composed of multiple parts to form a wedge-shaped whole effect. This design can be flexibly adjusted according to the specific use requirements and manufacturing process, so as to achieve the best clamping performance and structural stability between the memory metal member 2 and the sealing member 1.
[0048] Wherein, if the engaging portion 21 is wedge-shaped as a whole, the engaging portion 21 is in interference fit with the sealing member 1. If the engaging portion 21 is composed of multiple parts, in this embodiment, the engaging portion 21 has a first engaging portion 211 and a second engaging portion 212, the first engaging portion 211 is wedge-shaped, and the second engaging portion 212 is at the end of the engaging portion 21 away from the wedge-shaped structure, and the second engaging portion 212 is in interference fit with the sealing member 1. Wherein, interference fit means that the engagement between the engaging portion 21 of the memory metal member 2 and the sealing member 1 can provide more reliable sealing effect for the battery cell to prevent liquid leakage. In addition, the design of the wedge-shaped structure with decreasing outer diameter enables the memory metal member 2 to be more tightly clamped in the sealing member 1 when inserted, thereby enhancing the strength and stability of the connection between the memory metal member 2 and the sealing member 1.
[0049] In this embodiment, the shape of the first engaging portion 211 is set as a circular truncated cone structure. Due to the shape characteristics of the circular truncated cone structure, once inserted and engaged, it has the characteristics of self-locking, which helps to maintain the engagement effect of the engaging portion 21 and the sealing member 1 when the memory metal member 2 is deformed, and enhances the safety and reliability of the structure.
[0050] Further, the memory metal member 2 further comprises a deformation portion 22 arranged at one end of the engaging portion 21. As shown in Figure 1 When the memory metal member 2 is in a heated state, the deformation portion 22 is parallel to the insertion direction of the engaging portion 21. In the heated state, the parallel characteristic of the deformation portion 22 and the engaging portion 21 can more conveniently enable the memory metal member 2 to be inserted into the sealing member 1 along the insertion direction, and enable the engaging portion 21 to be in interference fit with the sealing member 1, thereby achieving the preliminary sealing of the liquid injection hole 31.
[0051] As shown in Figure 2 , Figure 6 and Figure 7 When the memory metal member 2 is in a cooled state, the deformation portion 22 is perpendicular to the insertion direction of the engaging portion 21. Due to the deformation characteristics of the memory metal, the deformation portion 22 and the engaging portion 21 remain perpendicular in the cooled state. At this time, the deformation portion 22 of the memory metal member deforms and fits with the bottom of the sealing member 1, and the length of the deformation portion 22 exceeds the length of the fit with the sealing member 1, and the excess length can ensure that the deformation portion 22 can completely cover and fit the sealing member 1, and the length of the deformation portion 22 exceeding the fit with the sealing member 1 can provide additional contact area, thereby further enhancing the sealing effect and reducing the risk of leakage.
[0052] Further, the deformation portion 22 is provided with a plurality of deformation portions 22, and the plurality of deformation portions 22 are arranged in a ring shape at equal intervals. In Figures 6-8The number of the deformation portions 22 is shown as 4 in the figure. The ring-shaped equidistantly arranged deformation portions 22 can more evenly distribute stress and reduce local stress concentration, thereby reducing the risk of structural damage. In the embodiment, as shown in Figures 3-5 and Figure 9 In the heated state, the length of the memory metal piece 2 beyond the sealing piece 1 is h6, the length of the deformation portion 22 is h3, and h6=h3. In addition, in order to make the deformation portion 22 more evenly conduct heat during heating, the thickness range r1 of the deformation portion 22 can be 0.1mm-0.2mm, and the deformation portion 22 has a first curvature a, which is greater than 10°.
[0053] Further, the deformation portion 22 is provided in a long strip structure. The long strip structure shape memory metal has high strength and hardness, while still maintaining good ductility and toughness. And the long strip structure deformation portion 22 helps to more evenly distribute stress and reduce local stress concentration, thereby reducing the risk of overall structural damage.
[0054] Further, a gap is reserved between each two adjacent deformation portions 22 for switching between the heated state and the cooled state of the deformation portion 22, preventing the deformation portions 22 from interfering or jamming with each other during deformation, and ensuring that each deformation portion 22 can work independently and effectively.
[0055] Further, as shown in Figure 1 and Figure 2 The sealing piece includes a first sealing portion 11 and a second sealing portion 12, and the memory metal piece 2 penetrates the first sealing portion 11 and the second sealing portion 12 in turn.
[0056] Specifically, as shown in Figures 4-5 and Figure 9 The first sealing portion 11 has a wedge-shaped penetration hole. The upper diameter of the wedge-shaped penetration hole is d3, and the lower diameter is d4, d3>d4. The memory metal piece 2 can pass through the wedge-shaped penetration hole of the first sealing portion 11. It should be noted that the clamping portion 21 includes a first clamping portion 211 and a second clamping portion 212. The first clamping portion 211 is a circular truncated cone type, which is adapted to the shape of the wedge-shaped penetration hole of the first sealing portion 11, and the wedge-shaped penetration hole cooperates with the circular truncated cone type first clamping portion 211 on the memory metal piece 2 to provide stronger clamping force, thereby ensuring the sealing and reliability of the clamping connection between the memory metal piece 2 and the first sealing portion 211.
[0057] It should be noted that, as shown in Figures 4-5 and Figure 9As shown, the upper diameter of the first engaging portion 211 is d1, and the lower diameter is d2, and d1>d2. In consideration of the convenience of the first engaging portion 211 of the memory metal piece and the first sealing portion 11 in the assembly process, a gap of 0.1 mm can be reserved between the upper diameter d3 of the wedge-shaped through hole and the upper diameter d1 of the first engaging portion 211. In addition, the wedge-shaped through hole and the first engaging portion 211 have a first inclination angle, which is in the range of 5°-10°, so as to have a certain adjustment space in the assembly process to adapt to the slight tolerance in the manufacturing process. In order to ensure the precise engagement between the first engaging portion 211 and the first sealing portion 11, the height of the first engaging portion 211 is h1, and the height of the wedge-shaped through hole is h4, h1=h4.
[0058] Further, the second sealing portion 12 has a cylindrical through hole, and the memory metal piece 2 can pass through the cylindrical through hole to engage the second sealing portion 12 in interference. The memory metal piece 2 can pass through the cylindrical through hole and realize the interference engagement between the second engaging portion 212 and the second sealing portion 12, which reduces the additional assembly steps and the need for accessories. In addition, the interference engagement can ensure the close fit between the second engaging portion 212 of the memory metal piece 2 and the second sealing portion 12, maintain the sealing performance, and reduce the risk of leakage.
[0059] It should be noted that, as Figure 5 and Figure 9 , the lower diameter of the first engaging portion 211 is equal to the diameter of the second engaging portion 212, both of which are d2. The lower diameter of the wedge-shaped through hole is equal to the diameter of the cylindrical through hole, both of which are d4. The interference engagement between the second engaging portion 212 and the second sealing portion 12 is that the diameter d4 of the cylindrical through hole is smaller than the diameter d2 of the second sealing portion 212, which can ensure that the sealing member 1 is tightly engaged on the memory metal piece 2, thereby providing better sealing effect.
[0060] Further, the sealing member 1 is made of a material with elasticity and chemical resistance, such as rubber material and silica gel material. In this embodiment, the sealing member 1 is made of rubber material, which can not only interfere with the injection hole 31 to ensure that there is no gap between the sealing member 1 and the injection hole 31, thereby preventing the leakage of electrolyte, but also can interfere with the memory metal piece 2, thereby enhancing the structural stability of the entire sealing assembly, thereby reducing the risk of structural loosening under vibration or impact.
[0061] In this embodiment, as Figures 10-13 shown, in the process of assembling the sealing assembly 4 to the injection hole 31 of the cell cover plate 3, the injection hole 31 includes a first notch 311 and a second notch 312, the first notch 31 is engaged with the first sealing portion 11, and the second notch 32 is engaged with the second sealing portion 12.
[0062] Specifically, as shown in Figure 5 and Figure 10 To improve the sealing performance and structural stability of the sealing assembly 4, the outer diameter of the first notch 311 of the liquid injection hole 31 on the battery cover plate 3 is recorded as d7, and the first sealing part 11 is a circular truncated cone type with a decreasing outer diameter in the insertion direction, and the diameter thereof is recorded as d5. In order to have a certain adjustment space during assembly, d7>d5, such as d7-d5=0.1mm. The sidewall of the first sealing part 11 and the sidewall of the first notch 311 have a second inclination angle, and the range of the second inclination angle can be 3°-5°.
[0063] In the embodiment, the second sealing part 12 is a cylindrical shape, and the outer diameter thereof is recorded as d6. In order to reduce the interference between the first notch 311 of the liquid injection hole 31 and other components and the structural stability, the relationship between the outer diameter d7 of the first notch 311 and the outer diameter d6 of the second sealing part 12 can satisfy: d7>d6*1.5. In the area where the second notch 312 and the second sealing part 12 are engaged, the diameter of the second notch 312 is recorded as d8, and d6>d8, such as d6-d8=0.2mm.
[0064] In summary, the sealing assembly for sealing the liquid injection hole of the battery provided in the embodiment of the utility model realizes the detachable sealing of the liquid injection hole by the shape memory effect of the memory metal part and the shape change in the heating and cooling two different states, so as to solve the problem that the performance of the battery is reduced with the consumption of the electrolyte because the electrolyte in the battery cannot be replaced and supplemented in time in the prior art.
[0065] The above is only the preferred embodiment of the utility model, and does not limit the utility model in any way. Any person skilled in the art can make any form of equivalent replacement or modification of the technical scheme and technical content disclosed in the utility model without departing from the scope of the technical scheme of the utility model, and such change still belongs to the protection scope of the utility model.
Claims
1. A sealing assembly for sealing the electrolyte injection port of a battery cell, characterized in that, The sealing assembly comprises a sealing member and a memory metal member; The sealing member is matched with the liquid injection hole of the battery cell to realize sealing; The memory metal member has a heating state and a cooling state in the application process; When the memory metal member is in the heating state, one end of the memory metal member can penetrate the sealing member and extend to the outside of the liquid injection hole, and the other end is clamped and limited to the sealing member; When the memory metal member is in the cooling state, the end of the memory metal member extending to the outside of the liquid injection hole is deformed to be attached to the inner surface of the cover plate of the battery cell.
2. The seal assembly of claim 1, wherein, The memory metal member comprises a clamping portion; the clamping portion has a wedge-shaped structure, and the outer diameter of the wedge-shaped structure decreases along the insertion direction and is clamped to the sealing member.
3. The seal assembly of claim 2, wherein, The end of the clamping portion away from the wedge-shaped structure is in interference fit with the sealing member.
4. The seal assembly of claim 2, wherein, The memory metal member further comprises a deformation portion arranged at one end of the clamping portion; When the memory metal member is in the heating state, the deformation portion is parallel to the insertion direction of the clamping portion; When the memory metal member is in the cooling state, the deformation portion is perpendicular to the insertion direction of the clamping portion.
5. The seal assembly of claim 4, wherein, The deformation portion is arranged in multiple, and the multiple deformation portions are arranged in a ring shape at equal intervals.
6. The seal assembly of claim 5, wherein, The deformation portion is arranged in a long strip type structure.
7. The seal assembly of claim 6, wherein, A gap is reserved between the adjacent two deformation portions for switching between the heating state and the cooling state of the deformation portion.
8. The seal assembly of claim 1, wherein, The sealing member comprises a first sealing portion and a second sealing portion, and the memory metal member penetrates the first sealing portion and the second sealing portion in sequence.
9. The seal assembly of claim 8, wherein, The first sealing portion has a wedge-shaped penetration hole, and the memory metal member can penetrate the wedge-shaped penetration hole of the first sealing portion to clamp the first sealing portion; the second sealing portion has a cylindrical penetration hole, and the memory metal member can penetrate the cylindrical penetration hole to interfere with the second sealing portion.
10. The seal assembly of claim 1, wherein, The sealing member is made of a material having elasticity and chemical resistance.