Battery cell pressure relief structure and battery cell

Abstract

The utility model discloses an embodiment provides a kind of electric core pressure relief structure and electric core, it is related to battery technical field.The utility model provides electric core pressure relief structure including shell, and the through-hole is opened in shell, and the through-hole inner wall is set with protruding portion around one end close to electric core interior;Lower pressing plate, it is movably set in through-hole;Upper pressing plate, it is fixedly set in shell and is used to block through-hole, and upper pressing plate is opened with exhaust hole;Elastic piece, it is set between lower pressing plate and upper pressing plate, to be used for with lower pressing plate to resist to the protruding portion on;Waterproof air-permeable membrane, it is set in protruding portion, to be used for blocking through-hole.The utility model provides electric core including above-mentioned electric core pressure relief structure.The utility model can discharge electric core interior gas in time, and make electric core can be reused.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and more specifically, to a cell pressure relief structure and a cell. Background Technology

[0002] After a battery cell is manufactured and rolled off the production line, gas will be generated inside it during charging, discharging, or storage. The generation of gas will have a negative impact on various performance aspects of the battery cell, such as increased internal resistance, reduced capacity, shortened cycle life, and deformation caused by cell expansion. In extreme cases, excessive internal gas pressure can lead to battery cell explosion and cause safety issues. Therefore, the gas inside the battery cell needs to be released in a timely manner.

[0003] The current common measure is to add an explosion-proof valve to the battery cell structure. When the internal pressure of the battery cell reaches the explosion-proof valve's set burst pressure range, the explosion-proof valve breaks open, releasing the internal pressure of the battery cell. However, after releasing the pressure in this way, the explosion-proof valve is damaged, and the battery cell is also scrapped. This is a destructive directional pressure release method for the battery cell.

[0004] Therefore, there is an urgent need to design a battery cell that can expel internal gases in a timely manner and enable the battery cell to be reused. Utility Model Content

[0005] The purpose of this invention is to provide a battery cell pressure relief structure and a battery cell that can promptly release internal gas and enable the battery cell to be reused.

[0006] The embodiments of this utility model can be implemented as follows: In a first aspect, this utility model provides a cell pressure relief structure, comprising: The outer casing has a through hole, and a protrusion is arranged around one end of the inner wall of the through hole near the inside of the battery cell; The lower pressure plate is movably disposed within the through hole; An upper pressure plate is fixedly installed on the outer shell and used to block the through hole; an exhaust hole is provided on the upper pressure plate. An elastic element is disposed between the lower pressure plate and the upper pressure plate to hold the lower pressure plate against the protrusion. A waterproof and breathable membrane is disposed on the protrusion to seal the through hole.

[0007] In an optional embodiment, the cell pressure relief structure further includes a sealing ring disposed between the lower pressure plate and the protrusion.

[0008] In an optional embodiment, the sealing ring is made of an elastic material.

[0009] In an optional embodiment, the protrusion includes opposing first and second surfaces, with the waterproof and breathable membrane disposed on the first surface; or, The waterproof and breathable membrane is disposed on the second surface.

[0010] In an optional embodiment, the waterproof and breathable membrane is bonded to the protrusion.

[0011] In an optional embodiment, a stepped surface is provided around one end of the inner wall of the through hole away from the inside of the battery cell, and the upper pressure plate abuts against the stepped surface.

[0012] In an optional embodiment, the upper pressure plate is welded to the outer casing; or, The upper pressure plate is threadedly fixed to the outer casing.

[0013] In an optional embodiment, at least one vent is provided on the upper pressure plate.

[0014] In an optional embodiment, the elastic element comprises a spring; or, The elastic element includes a rubber elastomer.

[0015] Secondly, this utility model provides a battery cell, including the battery cell pressure relief structure described in any of the foregoing embodiments.

[0016] The beneficial effects of the battery cell pressure relief structure and the battery cell provided in this embodiment of the invention include: When the internal pressure of the battery cell gradually increases and exceeds the elastic force exerted by the elastic element on the lower pressure plate, the lower pressure plate is pushed up, creating a gap between the lower pressure plate and the protrusion, forming a gas channel. The gas inside the battery cell passes through the waterproof and breathable membrane, enters the space between the upper and lower pressure plates, and then exits to the outside of the battery cell through the vent holes on the upper pressure plate. Because the waterproof and breathable membrane prevents liquid penetration, the electrolyte inside the battery cell cannot flow to the outside of the battery cell through the waterproof and breathable membrane; only the internal gas can be discharged. As the internal gas pressure of the battery cell gradually decreases, the elastic element presses the lower pressure plate against the protrusion again, achieving a seal on the battery cell. Thus, the battery cell pressure relief structure provided in this embodiment can promptly discharge the gas inside the battery cell while allowing the battery cell to be reused. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1This is a top view of the cell pressure relief structure provided in this embodiment; Figure 2 This is an exploded view of the cell pressure relief structure provided in this embodiment; Figure 3 This is a cross-sectional view of the cell pressure relief structure provided in this embodiment; Figure 4 for Figure 3 Enlarged view of section A.

[0019] Icons: 100-Outer shell; 110-Through hole; 120-Protrusion; 121-First side; 122-Second side; 130-Stepped surface; 200-Lower pressure plate; 300-Upper pressure plate; 310-Ventilation hole; 400-Elastic element; 500-Waterproof and breathable membrane; 600-Sealing ring. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0022] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0023] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed during use, they are only for the convenience of describing this utility model and simplifying the description, and do not 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.

[0024] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0025] It should be noted that, where there is no conflict, the features in the embodiments of this utility model can be combined with each other.

[0026] As described in the background section, the gas inside the battery cell needs to be released promptly to prevent the cell from experiencing increased internal resistance, reduced capacity, expansion and deformation, or even explosion. Currently, explosion-proof valves are typically added to the battery cell structure. However, when the internal pressure of the cell exceeds the valve's set pressure, the valve bursts, releasing the internal pressure while simultaneously destroying the valve and rendering the cell unusable. This results in wasted battery cells, high cell costs, and the potential for the explosion of the valve to cause loss of life and property.

[0027] Based on this, the present invention provides a cell pressure relief structure and a cell to solve the above-mentioned problems. The overall structure, working principle, and technical effects of the cell pressure relief structure and cell provided by the present invention will be described in detail below through embodiments and in conjunction with the accompanying drawings.

[0028] Please refer to Figures 1-4 This utility model provides a battery cell pressure relief structure, including a housing 100, a lower pressure plate 200, an upper pressure plate 300, an elastic element 400, and a waterproof and breathable membrane 500. A through hole 110 is provided on the housing 100, communicating with the interior of the battery cell to discharge gas generated inside the cell. A protrusion 120 is arranged around the inner wall of the through hole 110 near the interior of the battery cell. The upper pressure plate 300 is movably disposed within the through hole 110 and fixedly disposed on the housing 100 at the through hole 110. The upper pressure plate 300 is used to seal the through hole 110 and has an exhaust hole 310. The elastic element 400 is disposed between the upper pressure plate 300 and the lower pressure plate 200. The elastic element 400 is always in an energy-storing state, meaning it always applies downward pressure to the lower pressure plate 200, pressing the lower pressure plate 200 against the protrusion 120. A waterproof and breathable membrane 500 is disposed on the protrusion 120 and is used to seal the through hole 110.

[0029] When the internal pressure of the battery cell gradually increases and exceeds the elastic force exerted by the elastic element 400 on the lower pressure plate 200, the lower pressure plate 200 is pushed up, creating a gap between the lower pressure plate 200 and the protrusion 120, forming a gas channel. The gas inside the battery cell passes through the waterproof and breathable membrane 500 and enters the space between the upper pressure plate 300 and the lower pressure plate 200. Then, it is discharged to the outside of the battery cell through the vent 310 on the upper pressure plate 300. Since the waterproof and breathable membrane 500 has the function of preventing liquid penetration, the electrolyte inside the battery cell cannot flow to the outside of the battery cell through the waterproof and breathable membrane 500, and can only discharge the internal gas. As the internal gas pressure of the battery cell gradually decreases, the elastic element 400 presses the lower pressure plate 200 against the protrusion 120 again, achieving a seal on the battery cell. Thus, the battery cell pressure relief structure provided in this embodiment can discharge the internal gas of the battery cell in a timely manner, while also enabling the battery cell to be reused.

[0030] Understandably, in this embodiment, the outer shell 100 is made of aluminum alloy or stainless steel. The cell pressure relief structure provided in this embodiment is applicable to cells with cylindrical, square or other structural shapes, as well as cells with aluminum shells, steel shells and different systems.

[0031] Please refer to Figure 2 and Figure 4 To improve the sealing effect between the lower pressure plate 200 and the protrusion 120, and enhance the sealing performance of the battery cell, in some optional embodiments, the battery cell pressure relief structure further includes a sealing ring 600, which is disposed between the lower pressure plate 200 and the protrusion 120. Furthermore, the sealing ring 600 is made of an elastic material such as fluororubber or EPDM rubber with compressibility. In actual use, the pressure of the elastic element 400 on the lower pressure plate 200 is transmitted to the sealing ring 600, causing the sealing ring 600 to compress and fill the gap between the lower pressure plate 200 and the protrusion 120, thereby achieving a complete seal between the lower pressure plate 200 and the outer casing 100.

[0032] Please refer to Figure 4 The protrusion 120 includes a first surface 121 and a second surface 122 facing each other, wherein the first surface 121 faces the interior of the battery cell. In some optional embodiments, a waterproof and breathable membrane 500 is disposed on the first surface 121 of the protrusion 120; in other optional embodiments, the waterproof and breathable membrane 500 is disposed on the second surface 122 of the protrusion 120. Whether the waterproof and breathable membrane 500 is disposed on the first surface 121 or the second surface 122, it can effectively prevent electrolyte from entering the through hole 110. The specific placement of the waterproof and breathable membrane 500 can be adaptively selected according to the battery cell design requirements, actual operating conditions, and other factors. Furthermore, to prevent the waterproof and breathable membrane 500 from detaching from the protrusion 120 and thus losing its function of preventing electrolyte from entering the through hole 110, in this embodiment, the waterproof and breathable membrane 500 is bonded to the protrusion 120.

[0033] Please refer to Figure 4 In some alternative embodiments, a stepped surface 130 is provided around the inner wall of the through hole 110 at one end away from the inside of the battery cell. The upper pressure plate 300 abuts against the stepped surface 130, and the outer side of the upper pressure plate 300 is flush with the surface of the outer casing 100. The stepped surface 130 facilitates the installation of the upper pressure plate 300 and makes the surface of the outer casing 100 flat and aesthetically pleasing. It also increases the contact area between the upper pressure plate 300 and the outer casing 100, thereby facilitating the fixing of the upper pressure plate 300 to the outer casing 100. Specifically, in this embodiment, the upper pressure plate 300 is welded to the outer casing 100, or the upper pressure plate 300 is threaded to the outer casing 100. In some alternative embodiments, the upper pressure plate 300 can also be fixedly connected to the outer casing 100 by other connection methods, such as bonding, pin connection, etc., as long as the connection strength between the upper pressure plate 300 and the outer casing 100 is greater than the elastic force of the elastic element 400 on the lower pressure plate 200. That is, when the pressure inside the cell increases, it will push up the lower pressure plate 200 first, and will not destroy the connection stability between the upper pressure plate 300 and the outer casing 100, thus avoiding damage to the pressure relief structure.

[0034] Please refer to Figure 1 , Figure 2 and Figure 3 In some optional embodiments, at least one vent 310 is provided on the upper pressure plate 300. In order to ensure the venting effect of the pressure relief structure when the internal pressure of the battery cell is too high, the number of vent 310 can be adaptively selected according to the design requirements of the battery cell.

[0035] Please refer to Figure 2 and Figure 4 The elastic element 400 includes a spring. In some alternative embodiments, the elastic element 400 may also include a rubber elastomer, as long as the elastic element 400 always has a downward elastic force on the lower pressure plate 200. In this embodiment, the specific structural form of the elastic element 400 is not limited.

[0036] On the other hand, this utility model also provides a battery cell, including the battery cell pressure relief structure in any of the above embodiments. The outer shell 100 is disposed on the surface of the battery cell as a battery cell cover or battery cell housing. The through hole 110 is used to connect the inside of the battery cell with the atmosphere. The battery cell pressure relief structure is used to timely remove the gas inside the battery cell, avoid the accumulation of gas inside the battery cell leading to excessive pressure, which affects the performance of the battery cell and does not damage the battery cell. In this way, the battery cell life can be greatly extended and the battery cell electrical performance and safety performance can be improved.

[0037] In summary, the battery cell pressure relief structure and its implementation principle provided by this utility model are as follows: When the internal pressure of the battery cell gradually increases and exceeds the elastic force applied by the elastic element 400 to the lower pressure plate 200, the lower pressure plate 200 is lifted, creating a gap between the lower pressure plate 200 and the protrusion 120, forming a gas channel. The gas inside the battery cell passes through the waterproof and breathable membrane 500 and enters the space between the upper pressure plate 300 and the lower pressure plate 200. Then, it is discharged to the outside of the battery cell through the vent 310 on the upper pressure plate 300. Since the waterproof and breathable membrane 500 has the function of preventing liquid penetration, the electrolyte inside the battery cell cannot flow to the outside of the battery cell through the waterproof and breathable membrane 500, and can only discharge the internal gas. As the internal gas pressure of the battery cell gradually decreases, the elastic element 400 presses the lower pressure plate 200 against the protrusion 120 again, achieving a seal on the battery cell. Thus, the battery cell pressure relief structure provided in this embodiment can discharge the internal gas of the battery cell in a timely manner while enabling the battery cell to be reused.

[0038] The above description is only a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model.

Claims

1. A cell pressure relief structure, characterized in that, include: The outer casing has a through hole, and a protrusion is arranged around one end of the inner wall of the through hole near the inside of the battery cell; The lower pressure plate is movably disposed within the through hole; An upper pressure plate is fixedly installed on the outer shell and used to block the through hole; an exhaust hole is provided on the upper pressure plate. An elastic element is disposed between the lower pressure plate and the upper pressure plate to hold the lower pressure plate against the protrusion. A waterproof and breathable membrane is disposed on the protrusion to seal the through hole.

2. The cell pressure relief structure according to claim 1, characterized in that, The cell pressure relief structure also includes a sealing ring, which is disposed between the lower pressure plate and the protrusion.

3. The cell pressure relief structure according to claim 2, characterized in that, The sealing ring is made of an elastic material.

4. The cell pressure relief structure according to claim 1, characterized in that, The protrusion includes a first surface and a second surface facing each other, and the waterproof and breathable membrane is disposed on the first surface; or... The waterproof and breathable membrane is disposed on the second surface.

5. The cell pressure relief structure according to claim 4, characterized in that, The waterproof and breathable membrane is bonded to the protrusion.

6. The cell pressure relief structure according to claim 1, characterized in that, The inner wall of the through hole has a stepped surface at one end away from the inside of the battery cell, and the upper pressure plate abuts against the stepped surface.

7. The cell pressure relief structure according to claim 1, characterized in that, The upper pressure plate is welded to the outer casing; or... The upper pressure plate is threadedly fixed to the outer casing.

8. The cell pressure relief structure according to claim 1, characterized in that, At least one vent is provided on the upper pressure plate.

9. The cell pressure relief structure according to claim 1, characterized in that, The elastic element includes a spring; or... The elastic element includes a rubber elastomer.

10. A battery cell, characterized in that, Includes the cell pressure relief structure as described in any one of claims 1-9.

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