Lithium battery shell and lithium battery
By setting a continuous wall-reducing groove structure on the lithium battery casing, the problems of high processing precision and high cost in the prior art are solved, achieving more efficient pressure relief and explosion-proof effects, which is suitable for square lithium batteries.
Patent Information
- Application Number
- CN202422810829.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-19
- Publication Date
- 2025-12-05
- Estimated Expiration
- 2034-11-19
AI Technical Summary
Existing lithium battery casings are prone to internal pressure relief designs when electrodes are short-circuited, which require high processing precision, are costly, and have poor pressure relief effects.
Continuous wall-reducing grooves are provided on the cover plate and/or bottom shell of the lithium battery casing, including straight groove sections and arc groove sections. The design is chamfered to facilitate milling, avoid the easily deformable but not easily bursting central position, and increase the weak area to facilitate pressure relief.
It improves processing accuracy and reduces processing difficulty and cost, while achieving better pressure relief and explosion-proof performance, making it suitable for square lithium batteries.
Smart Images
Figure CN223638541U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of lithium batteries, in particular to a square anti-explosion lithium battery shell and lithium battery. BACKGROUND
[0002] At present, lithium batteries are widely used in various industries and consumer fields, such as portable electronic products and electric vehicles, due to their high energy, small size, light weight, and safe and reliable advantages. However, due to improper use by users or abnormality of the battery itself, internal electrode short circuit faults are becoming more and more frequent. Once the electrode short circuit occurs, a large amount of heat and gas may accumulate in the battery in an instant, causing the internal pressure of the battery to rise, resulting in rapid expansion of the battery and explosion or fire, thereby causing damage to the battery.
[0003] To solve the above technical problems, the commonly used technical means in the prior art mainly includes:
[0004] 1. A pressure relief hole is opened on the battery shell and is covered with a metal foil for sealing. As the internal pressure of the battery rises, the metal foil bursts to achieve pressure relief. However, this design structure requires high processing precision and high cost for the equipment.
[0005] 2. A notch is provided in the middle of the wide face of the battery shell where deformation is easy to occur, and a weak link is formed to achieve pressure relief. However, the processing depth of the notch located in the center of the wide face is not easy to control during processing, and improper processing precision may cause damage to the battery shell or failure to relieve pressure in time and effectively, i.e., it also requires high precision for processing. In addition, when the battery expands, although a large deformation occurs in the middle of the wide face, the middle of the wide face may not be the most easily opened position due to the deformation of the battery shell made of metal material. Therefore, the design structure of providing a notch in the middle of the wide face makes it difficult to open the notch and does not achieve the desired anti-explosion effect.
[0006] The information disclosed in this BACKGROUND section is only intended to increase an understanding of the general context of the present application, and should not be taken as an acknowledgement or any form of suggestion that this information forms prior art that is publicly known. CONTENT OF THE UTILITY MODEL
[0007] The purpose of the present application is to provide a lithium battery shell and lithium battery with simple structure, easy production and processing, and high pressure relief sensitivity.
[0008] To achieve the above purpose, the present application adopts the following technical solutions:
[0009] In one aspect, the application provides a lithium battery shell, comprising a bottom shell and a cover plate, the bottom shell is provided with a cell mounting port; the cover plate is covered on the cell mounting port and is sealingly connected with the bottom shell, thereby forming a sealed cell accommodating cavity; the cover plate and / or the bottom shell is provided with a continuous wall-reduced groove, the wall-reduced groove comprises a linear groove segment and an arc-shaped groove segment.
[0010] The linear groove segment extends from the edge of the cover plate and / or the bottom shell to the inside and communicates with the arc-shaped groove segment.
[0011] Optionally, the included angle between the groove wall of the arc-shaped groove segment and the groove bottom of the arc-shaped groove segment is obtuse.
[0012] Optionally, the included angle between the groove wall of the linear groove segment and the groove bottom of the linear groove segment is a right angle, an acute angle or an obtuse angle.
[0013] Optionally, the bottom shell is provided with electrode mounting holes corresponding to the positive and negative output ends of the cell.
[0014] Optionally, the residual thickness of the wall-reduced groove is 0.1-0.3mm; the width of the wall-reduced groove is 0.5-1.0mm; the extension length of the wall-reduced groove is 1 / 3-1 / 2 of the width of the plane where it is located.
[0015] Optionally, the cover plate and / or the bottom shell is further provided with a pressure relief safety valve.
[0016] In another aspect, the application also provides a lithium battery, comprising a cell, and further comprising the lithium battery shell of any one of the preceding aspects, the cell is arranged in the cell accommodating cavity, and the cell accommodating cavity is filled with electrolyte.
[0017] Optionally, the cell is connected with a tab avoiding piece, the tab avoiding piece is provided with avoiding holes corresponding to the positive and negative output ends of the cell.
[0018] Optionally, the tab avoiding piece comprises a connecting plate and a bent edge connected with the connecting plate, the connecting plate is connected with the cell; the bent edge is bent towards the side surface of the cell where the positive and negative output ends are arranged and is fitted with the side surface of the cell.
[0019] Optionally, the lithium battery shell is square.
[0020] Compared with the prior art, the application can at least achieve the following beneficial effects:
[0021] 1. The application is provided with a continuous wall-reduced groove on the cover plate and / or the bottom shell. Compared with the pressure relief safety valve made of metal foil in the prior art, the structure is simple and the cost is low. Compared with the existing design structure of the notch in the middle of the wide surface, the depth of the wall-reduced groove is easier to control, which helps to improve the processing precision and thus improve the yield of the product. The wall-reduced groove includes a linear groove section and an arc-shaped groove section. The linear groove section extends from the edge of the cover plate and / or the bottom shell to the inside. The edge position of the cover plate and / or the bottom shell is smaller in terms of deformation and more prone to explosion, achieving better pressure relief effect. At the same time, under the same explosion pressure, if the same pressure relief effect is to be achieved, the wall-reduced groove provided by the application can be set to a shallower processing depth, thereby further reducing the processing difficulty, processing precision and processing cost. The end of the wall-reduced groove is designed as an arc-shaped groove section, which is in communication with the linear groove section to form a continuous wall-reduced groove. The design structure of the wall-reduced groove can be machined by using existing milling cutters, and the arc-shaped groove section at the end is more suitable for milling cutter machining.
[0022] 2. The lithium battery provided by the application adopts the lithium battery shell described above, has good pressure relief and explosion-proof effect, and has the advantage of low processing cost.
[0023] 3. The lithium battery provided by the application is further provided with a tab avoiding piece, which aims to avoid the phenomenon of short circuit of the positive and negative plates of the battery cell caused by tensile stress interference during tab welding.
[0024] 4. The lithium battery shell provided by the application is suitable for square lithium batteries and can be made of rigid metal materials, thereby achieving better pressure relief and explosion-proof effect. BRIEF DESCRIPTION OF DRAWINGS
[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the drawings needed in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor.
[0026] Figure 1 is a structural schematic view of the wall-reduced groove provided by an embodiment of the application when arranged on the cover plate;
[0027] Figure 2 is Figure 1 is a partial enlarged structural schematic view of the cover plate at the wall-reduced groove;
[0028] Figure 3 is Figure 1 is a chamfer design structural schematic view of the wall-reduced groove.
[0029] Figure 4 is a structural schematic diagram of a lithium battery provided by an embodiment of the present application;
[0030] Figure 5 is Figure 4 an exploded view.
[0031] Explanation of reference signs:
[0032] 01: lithium battery;
[0033] 100: positive output end; 101: negative output end;
[0034] 02: battery cell;
[0035] 200: bottom shell; 201: tab avoiding piece; 202: positive output end mounting hole; 203: negative output end mounting hole;
[0036] 03: cover plate;
[0037] 30: wall-reduced groove; 300: straight groove segment; 301: arc-shaped groove segment. DETAILED DESCRIPTION
[0038] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. The description of the at least one exemplary embodiment is actually only illustrative, but not as any limitation on the present application and its application or use. Embodiment one
[0039] The present embodiment provides a lithium battery shell, which at least includes a bottom shell 200 and a cover plate 03. The bottom shell 200 is in a semi-open structure, and an installation opening of the battery cell 02 is formed on the bottom shell 200 for installing the battery cell 02. The cover plate 03 is covered at the installation opening of the battery cell 02 and is sealingly connected with the bottom shell 200, so as to form a sealed battery cell 02 accommodating cavity.
[0040] When the internal pressure of the battery cell 02 accommodating cavity rapidly rises, in order to timely and effectively release the pressure, the present embodiment sets a wall-reduced groove 30 on the cover plate 03. Since the wall thickness of the wall-reduced groove 30 is smaller than that of other parts of the cover plate 03, the mechanical strength is also lower. Therefore, the weak area can be formed on the cover plate 03 by setting the wall-reduced groove 30, so as to facilitate the subsequent pressure release.
[0041] It should be noted that the cover plate 03 is a wide surface of the lithium battery shell, and the middle part is more prone to deformation relative to the edge. However, research shows that the part prone to deformation is not necessarily more prone to explosion and pressure relief, and the middle part of the cover plate 03 is affected by environmental factors, and the pressure relief pressure is not easy to calculate and control. Therefore, the wall-reduced groove 30 provided in the embodiment avoids the middle part of the cover plate 03 and extends from the edge of the cover plate 03 to the inside of the cover plate 03. Specifically, as shown in Figure 1 、 Figure 2 In the embodiment, the wall-reduced groove 30 is designed as a continuous groove, including a linear groove segment 300 and an arc-shaped groove segment 301. The linear groove segment 300 extends from the edge of the cover plate 03 to the middle part of the cover plate 03. The edge of the cover plate 03 is less affected by external factors and is more likely to open in time when the internal pressure of the shell rises. Moreover, compared with directly processing a notch structure in the middle part of the wide surface of the cover plate 03, the depth of the wall-reduced groove 30 derived from the edge of the cover plate 03 is easier to control and helps to improve the processing precision and thus the yield of products. The arc-shaped groove segment 301 is closer to the middle part of the cover plate 03 than the linear groove segment 300, and the arc-shaped groove segment 301 is in communication with the end of the linear groove segment 300. Compared with the design of opening a pressure relief hole in the cover plate 03, the design structure can expand the coverage area while ensuring the mechanical strength of the shell, so that the position prone to explosion and pressure relief falls into the weak area formed by the wall-reduced groove 30.
[0042] The wall-reduced groove 30 provided in the embodiment can be provided in multiple numbers. To ensure the mechanical strength of the shell, the wall-reduced groove 30 is distributed as much as possible in the position prone to pressure relief, such as being arranged near the diagonal line of the cover plate 03 of the square lithium battery shell. The overall shape of the wall-reduced groove 30 can also be designed as other shapes in consideration of the convenience of processing and the effect of pressure relief.
[0043] Compared with the existing design structure of using a wide surface notch to achieve pressure relief, the wall-reduced groove 30 provided in the embodiment can be set to a shallower processing depth to achieve the same pressure relief effect under the same explosion pressure, thereby further reducing the processing difficulty, processing precision, and processing cost.
[0044] Compared with the pressure relief safety valve made of a metal foil in the prior art, the wall-reduced groove 30 provided in the embodiment has a simple structure and low cost, and the arc-shaped groove segment 301 at the end of the wall-reduced groove 30 is more suitable for milling cutter processing.
[0045] As a deformation, the wall-reduced groove 30 used in the embodiment can also be arranged on the bottom shell 200.
[0046] For the convenience of production and processing, the linear groove section 300 and the arc-shaped groove section 301 can be designed as a chamfer structure, such as Figure 3 As shown, the included angle between the groove wall of the arc-shaped groove section 301 and the groove bottom of the arc-shaped groove section 301 is obtuse. The included angle between the groove wall of the linear groove section 300 and the groove bottom of the linear groove section 300 is a right angle, an acute angle or an obtuse angle.
[0047] In some embodiments, the bottom shell 200 is provided with electrode mounting holes corresponding to the positive electrode output end 100 and the negative electrode output end 101 of the battery cell 02, such as Figure 5 The positive electrode output end mounting hole 202 and the negative electrode output end mounting hole 203 are shown in
[0048] The lithium battery shell provided in the present application is suitable for square lithium batteries 01, is made of rigid metal materials, and has a residual thickness of the wall-reducing groove 30 of 0.1-0.3 mm and a width of the wall-reducing groove 30 of 0.5-1.0 mm to achieve better pressure relief effect and facilitate production and processing under the condition of normal use. The extension length of the wall-reducing groove 30 is 1 / 3-1 / 2 of the width of the plane where it is located. Taking the cover plate 03 as an example, the direction of extension of the wall-reducing groove 30 is determined as the width direction of the cover plate 03, and the length of the wall-reducing groove 30 extending inward from the edge of the cover plate 03 should be between 1 / 3 and 1 / 2 of the width of the cover plate 03. If the wall-reducing groove 30 extends inward from the diagonal position of the edge of the cover plate 03, the length thereof should be between 1 / 3 and 1 / 2 of the diagonal line length of the cover plate 03.
[0049] It should be noted that the wall-reducing groove 30 provided in the present embodiment can be used alone or in combination with other pressure relief safety valves, and therefore, a pressure relief safety valve can also be provided on the cover plate 03 and / or the bottom shell 200. Embodiment Two
[0050] As shown in Figure 4 and 5 The present embodiment provides a lithium battery 01, which comprises a battery cell 02 and a shell. The shell can adopt the lithium battery shell described in Embodiment One. The battery cell 02 is installed in the battery cell 02 accommodating cavity, and electrolyte is also injected into the battery cell 02 accommodating cavity. Since the lithium battery 01 provided in the present embodiment adopts the lithium battery shell described in Embodiment One, it also has good pressure relief and explosion prevention effect, and has the advantage of low processing cost.
[0051] The lithium battery 01 provided in the embodiment has a cell 02 mainly including a positive electrode, a negative electrode, a separator, a tab and a film. The positive electrode is usually made of aluminum (Al) material, the negative electrode is made of nickel (Ni) material or copper-plated nickel (Ni-Cu) material, and they are both composed of a film and a metal strip. The tab is a metal conductor for leading the positive and negative electrodes out of the cell 02, and is used to provide a contact point for charging and discharging. The film is an insulating part on the tab, and its function is to prevent short circuit and liquid leakage when the battery is packaged.
[0052] As shown in Figure 5 , during assembly, the cell 02 is installed in the bottom shell 200 of the lithium battery shell, and the positive output end 100 and the negative output end 101 of the cell 02 are led out from the bottom shell 200 through the electrode mounting hole.
[0053] In order to avoid the interference of tensile stress during tab welding, which may cause short circuit of the positive and negative electrodes, in the embodiment, the cell 02 is also connected with a tab avoiding piece 201, and the tab avoiding piece 201 is provided with avoiding holes corresponding to the positive output end 100 and the negative output end 101 of the cell 02.
[0054] Continuing to refer to Figure 5 , as an embodiment, the tab avoiding piece 201 includes a connecting plate and a bent edge connected with the connecting plate, the connecting plate is connected with the cell 02, and the bent edge is bent towards the side of the cell 02 where the positive output end 100 and the negative output end 101 are arranged, and is fitted with the side of the cell 02. The connecting plate and the bent edge can be formed in one piece, and the material can be selected from 304 or 316 sheet metal.
[0055] The lithium battery 01 structure provided in the embodiment can be applied to square steel shell lithium battery 01, and has the technical effects of simple structure, high pressure relief sensitivity, easy processing and low cost.
[0056] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are used only to explain the relative position relationship, movement condition and the like between the components in a certain posture, if the certain posture changes, the directional indication also changes accordingly. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.
[0057] In addition, the terms "first", "second", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance or an indicated number of technical features. Therefore, the features defined with "first", "second", etc. can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified and limited, the term "a plurality of" means two or more.
[0058] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "mounting", "connecting", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0059] The above is only the preferred embodiment of the present application, it should be pointed out that, for those skilled in the art, without departing from the technical principles of the present application, a number of improvements and modifications can be made, these improvements and modifications should also be regarded as the protection scope of the present application.
Claims
1. A lithium battery case, comprising a bottom shell and a cover plate, the bottom shell being provided with a cell mounting opening; the cover plate being sealedly connected with the bottom shell at the cell mounting opening, so as to form a sealed cell accommodating cavity; characterized in that, The cover plate and / or the bottom shell is provided with a continuous wall-reduced groove, the wall-reduced groove comprising a linear groove section and an arc-shaped groove section; The linear groove section extends from the edge of the cover plate and / or the bottom shell to the inside and communicates with the arc-shaped groove section.
2. The lithium battery case according to claim 1, wherein, The included angle between the groove wall of the arc-shaped groove section and the groove bottom of the arc-shaped groove section is obtuse.
3. The lithium battery case of claim 1, wherein, The included angle between the groove wall of the linear groove section and the groove bottom of the linear groove section is a right angle, an acute angle or an obtuse angle.
4. The lithium battery case of claim 1, wherein, The bottom shell is provided with electrode mounting holes corresponding to the positive output end and the negative output end of the battery cell.
5. The lithium battery case of claim 1, wherein, The residual thickness of the wall-reduced groove is 0.1-0.3mm; the width of the wall-reduced groove is 0.5-1.0mm; and the extension length of the wall-reduced groove is 1 / 3-1 / 2 of the width of the plane where the wall-reduced groove is located.
6. The lithium battery case of claim 1, wherein, The cover plate and / or the bottom shell is further provided with a pressure relief safety valve.
7. A lithium battery comprising a cell, characterized in that, The lithium battery shell further comprises the battery cell accommodated in the battery cell accommodating cavity, and the battery cell accommodating cavity is filled with electrolyte.
8. The lithium battery of claim 7, wherein, The battery cell is connected with a tab avoiding piece, the tab avoiding piece is provided with avoiding holes corresponding to the positive output end and the negative output end of the battery cell.
9. The lithium battery of claim 8, wherein, The tab avoiding piece comprises a connecting plate and a bent edge connected with the connecting plate, the connecting plate is connected with the battery cell; and the bent edge is bent towards the side surface of the battery cell where the positive output end and the negative output end are arranged and is in close contact with the side surface of the battery cell.
10. The lithium battery of claim 7, wherein, The lithium battery shell is square.