Battery and battery production method

Abstract

The application provides a battery and a battery preparation method. The convex edge of the second bending part of the sealing structure is abutted to the negative current collector plate. The structural relationship between the existing sealing structure and the negative current collector plate is optimized. When the battery is subjected to vibration and collision, the impact point and the sealing surface are not directly affected. Meanwhile, the battery has the ability to absorb certain deformation and impact force. In addition, the sealing property can be ensured, and the battery can be prevented from leaking, exploding and the like, thereby improving the safety of the battery.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to batteries and battery preparation methods. Background Technology

[0002] Lithium-ion batteries possess outstanding advantages such as high energy density, low environmental pollution, high power density, long lifespan, wide applicability, and low self-discharge coefficient, making them one of the most widely used batteries in the world today and a crucial component of new energy development. A lithium-ion battery cell is assembled from positive and negative electrodes and a separator through winding or stacking to form an electrode assembly (bare cell), which is then installed in a casing, capped, and finally filled with electrolyte. However, with the continuous development of lithium-ion battery technology, higher requirements have been placed on the quality and safety of lithium-ion batteries. However, the sealing strength of existing battery technologies is insufficient, leading to the risk of leakage and failure. Summary of the Invention

[0003] The embodiments of this application provide a battery and a battery manufacturing method, which can improve the technical problem that the sealing technology of batteries in the prior art is still insufficient, resulting in significant safety hazards during later use.

[0004] In a first aspect, embodiments of this application provide a battery, comprising:

[0005] The housing has a receiving cavity and a first opening communicating with the receiving cavity. The housing has a sealing structure on one side of the first opening, and the sealing structure includes a first bent portion and a second bent portion connected in sequence.

[0006] A negative current collector is built into the receiving cavity, and the convex edge of the second bent portion abuts against the negative current collector.

[0007] In one embodiment, the battery further includes a cover plate, and the sealing structure further includes a third bend, which is connected to the second bend. The cover plate abuts against the inner side of the third bend and is connected to the negative current collector.

[0008] In one embodiment, the cover plate is provided with at least one explosion-proof groove.

[0009] In one embodiment, the battery further includes a seal located at the contact point between the cover plate and the third bend, the seal being used to seal the cover plate and the third bend.

[0010] In one embodiment, both the third bend and the seal are U-shaped structures, the seal is adapted to the third bend, and the raised edge of the cover plate abuts against the U-shaped structure of the seal.

[0011] In one embodiment, both the third bend and the seal are L-shaped structures. The seal is adapted to the third bend, and the inner sides of both sides of the seal are provided with a locking structure. The raised edge of the cover plate abuts against the seal, and the locking structure engages with the raised edge of the cover plate.

[0012] In one embodiment, the negative collector is connected to the housing, and the connection between the negative collector and the housing is located within the groove of the first bend.

[0013] In one embodiment, the negative current collector includes an electrical connection structure, which is a protrusion of a preset shape, and the protrusion is in elastic contact with the cover plate.

[0014] In one embodiment, the battery further includes an electrode assembly built into the receiving cavity. The electrode assembly includes a core, and the negative current collector is connected to the core. The convex edge of the second bend abuts against the side of the negative current collector away from the core.

[0015] In one embodiment, the convex edge of the second bend is in close contact with the negative collector disk.

[0016] Secondly, embodiments of this application provide a battery manufacturing method, the method comprising:

[0017] A housing is provided, the housing having a receiving cavity and a first opening communicating with the receiving cavity;

[0018] A negative collector disk is provided, and the negative collector disk is built into the receiving cavity;

[0019] The shell is bent inward at a preset angle at a first preset length from the first opening to obtain an initial bent structure of the first preset length.

[0020] Grooving is performed at a preset position of the initial bending structure to form a sealing structure. The sealing structure includes a first bending part and a second bending part connected in sequence, wherein the convex edge of the second bending part of the sealing structure abuts against the negative collector disk.

[0021] In one embodiment, the method further includes:

[0022] A cover plate is provided, which is disposed inside the housing and connected to the negative collector plate;

[0023] A sealing element is provided and placed on the raised edge of the cover plate. The sealing structure is mechanically pressed together using a pre-set mold to form a third bend, so that the third bend and the cover plate are sealed.

[0024] In one embodiment, before bending the housing at a preset angle inward at a first preset length from the first opening to obtain an initial bent structure of the first preset length, the method further includes:

[0025] The negative current collector is welded to the inner side of the housing;

[0026] After grooving is performed at the preset position of the initial bending structure, the weld between the negative current collector and the inner side of the housing is located in the groove of the first bending part.

[0027] The beneficial effects of the embodiments of this application are as follows:

[0028] The battery provided in this application includes a housing with a receiving cavity and a first opening communicating with the receiving cavity. The housing has a sealing structure on one side of the first opening, the sealing structure including a first bent portion and a second bent portion connected in sequence; and a negative current collector, the negative current collector being built into the receiving cavity. The protruding edge of the second bent portion abuts against the negative current collector. Compared to traditional batteries, by having the protruding edge of the second bent portion of the sealing structure abut against the negative current collector, the structural relationship between the existing sealing structure and the negative current collector is optimized. This ensures that when the battery experiences vibration or collision, the impact point does not directly interact with the sealing surface. Simultaneously, it has the ability to absorb a certain amount of deformation and impact force, and also ensures sealing, preventing battery leakage and explosion, thus improving battery safety. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a cross-sectional schematic diagram of a battery provided in an embodiment of this application;

[0031] Figure 2 This is a partially enlarged schematic diagram of the first sealing structure in the preparation process provided in the embodiments of this application;

[0032] Figure 3This is a partially enlarged schematic diagram of the second sealing structure in the preparation process provided in the embodiments of this application;

[0033] Figure 4 This is a partially enlarged schematic diagram of the third sealing structure in the preparation process provided in the embodiments of this application;

[0034] Figure 5 This is a partially enlarged schematic diagram of another sealing structure provided in an embodiment of this application;

[0035] Figure 6 This is a top view of the negative collector disk provided in an embodiment of this application;

[0036] Figure 7 This is a schematic flowchart of the battery manufacturing method provided in the embodiments of this application. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0038] In the following text, the terms "battery module," "battery," "battery element," "cell," and "battery pack" are used interchangeably and can refer to any of a variety of rechargeable battery chemistry and construction, including but not limited to lithium-ion (e.g., lithium-ion phosphate, lithium cobalt oxide, lithium iron phosphate, other lithium oxide metals, etc.), lithium-ion polymer, nickel-metal hydride, nickel-cadmium, nickel-metal hydride, nickel-zinc, silver-zinc, or other battery types / constructions. The term "electric vehicle" is used herein to refer to a fully electric vehicle also known as an EV, a plug-in hybrid electric vehicle also known as a PHEV, or a hybrid electric vehicle (HEV), wherein the hybrid vehicle employs multiple propulsion sources, one of which is an electric drive system. It should be understood that the same reference numerals are used in multiple figures to refer to the same components or components with equivalent functions, and various modifications to the preferred embodiments, general principles, and features described herein will be apparent to those skilled in the art. Furthermore, the figures are intended to illustrate the scope of this application only and are not intended to be limiting and should not be considered to be drawn to scale.

[0039] The embodiments of this application are generally applicable to systems employing electric motors, and more specifically, but not exclusively, to electric vehicles using multiphase electric motors (e.g., inductive motors). Electric vehicles use one or more stored energy sources, such as battery packs, to provide electrical power to the vehicle. This energy is at least partially used to propel the vehicle. The stored energy can also be used to provide power for other vehicle systems, such as vehicle lighting, vehicle-zoned heating, ventilation, and air conditioning (HVAC) systems, auxiliary control systems (e.g., sensors, displays, navigation systems, etc.), vehicle entertainment systems (e.g., radio, DVD, MP3, etc.), etc. Conventional electric vehicles include passenger vehicles and vehicles designed to transport goods, examples of which include passenger cars, trucks, electric bicycles, and recreational boats. Electric vehicles also include specialized work vehicles and trolleys, some of which may integrate features such as forklifts, scissor lifts, lifting and / or articulated boom lifts, cleaning systems, conveyors, and flatbed transport platforms.

[0040] The inventors of this application have discovered that the sealing strength of existing batteries is insufficient, leading to the risk of leakage and failure. Therefore, this application provides a battery in which the convex edge of the second bend of the sealing structure abuts against the negative current collector, optimizing the structural relationship between the existing sealing structure and the negative current collector. This ensures that when the battery experiences vibration or impact, the impact point does not directly interact with the sealing surface, while simultaneously absorbing a certain amount of deformation and impact force. Furthermore, it ensures airtightness, preventing battery leakage and explosion, thus improving battery safety. For details, please refer to the following description.

[0041] Please see Figures 1-6 , Figure 1 A schematic cross-sectional view of a battery provided for an embodiment of this application. Figures 2 to 4 These are partially enlarged schematic diagrams of the sealing structure during the preparation process provided in the embodiments of this application. Figure 5 A partially enlarged schematic diagram of another sealing structure provided for an embodiment of this application. Figure 6 A top view of a negative current collector provided in an embodiment of this application shows a battery 10, comprising: a housing 101 having a receiving cavity and a first opening communicating with the receiving cavity; a sealing structure on one side of the first opening, the sealing structure including a first bent portion 1021 and a second bent portion 1022 connected in sequence; and a negative current collector 105 housed within the receiving cavity, the protruding edge of the second bent portion 1022 abutting against the negative current collector 105. The first bent portion 1021 is bent along a predetermined first direction, and the second bent portion 1022 is bent along a predetermined second direction.

[0042] In this embodiment, the sealing structure is part of the shell 101. It can be understood that the sealing structure is obtained by bending the part of the shell 101 near the first opening. The first direction and the second direction are different in orientation, specifically they can be opposite. Specifically, the first bending part 1021 and the second bending part 1022 can be realized by a single grooving process, rather than by bending the shell 101 multiple times. The first direction and the length direction of the shell 101 can be parallel.

[0043] Compared to a traditional battery 10, the battery 10 provided in this application uses the convex edge of the second bend 1022 of the sealing structure to abut against the negative current collector 105, optimizing the structural relationship between the existing sealing structure and the negative current collector 105. This ensures that when the battery 10 experiences vibration or collision, the impact point does not directly interact with the sealing surface. At the same time, it has the ability to absorb a certain amount of deformation and impact force, and it can also ensure sealing, preventing leakage or explosion of the battery 10, thereby improving the safety of the battery 10.

[0044] In addition, the battery also includes an electrode assembly, which is built into the receiving cavity. The electrode assembly includes a core 1033, and the negative current collector 105 is connected to the core 1033. The convex edge of the second bending portion 1022 abuts against the side of the negative current collector 105 away from the core 1033. The electrode assembly may also include tabs, etc. The convex edge of the second bending portion 1022 is tightly fitted with the negative current collector 105 to achieve a certain core pressing amount. This core pressing amount depends on the depth of the grooving process mentioned above.

[0045] It should be noted that, in addition to the structure described above, the battery 10 may also include an insulating component 1031, a sealing component 1032, etc. Since these components are conventional existing structures, they will not be described in detail here.

[0046] Furthermore, the current "S"-shaped sealing structure of cylindrical batteries has several drawbacks. During sealing, the force direction is aligned with the thickness direction of the cover plate, and the cover plate is relatively thin. This makes the cover plate susceptible to deformation due to shear forces, leading to unstable valve opening and affecting battery safety. During drop tests on the negative electrode side, the sealing point may experience leakage failure due to insufficient strength. During vibration tests, the vibration direction aligns with the battery's axial direction, reducing the width of the groove and affecting the overall battery height, thus increasing the risk of breakage at the weld points where the busbar is attached to the battery. Finally, due to limitations in battery height and capacity, the available dimensions for the sealing structure in the height direction are limited, making it difficult to effectively balance height dimensions and sealing requirements.

[0047] In some embodiments of this application, from the perspective of improving the safety of the battery 10, the battery 10 further includes a cover plate 107, the cover plate 107 is provided with at least one explosion-proof groove 109, the sealing structure further includes a third bending portion 1023, the third bending portion 1023 is connected to the second bending portion 1022, the cover plate 107 abuts against the inner side of the third bending portion 1023 and is connected to the negative current collector 105.

[0048] Furthermore, this application continues to focus on improving the sealing performance of the cover plate 107 of the battery 10. A sealing element 108 can be provided at the contact position between the cover plate 107 and the third bend portion 1023 to improve the sealing performance of the sealing element 108. For example, the battery 10 may also include a sealing element 108, which is located at the abutment of the cover plate 107 and the third bend portion 1023. The sealing element 108 is used to seal the cover plate 107 and the third bend portion 1023. Thus, by providing a sealing element 108 at the abutment of the cover plate 107 and the third bend portion 1023, it is not necessary to fix and weld the cover plate 107 and the third bend portion 1023, thereby achieving a certain deformation tolerance.

[0049] The sealing structure of this application adopts a radial mechanical compression seal. Compared with the existing axial mechanical compression seal, this sealing method eliminates the need to apply additional sealing pressure after compression to reduce the groove width and maintain the overall height of the battery 10. It maintains the stability of the diameter at the connection between the bend and the shell wall, overcoming the limitation of sealing height under the requirements of battery 10 height and capacity. While maintaining the internal space of the battery 10, the thicknesses of the sealing element 108 and the cover plate 107 can be arbitrarily combined to ensure sealing requirements. It avoids the unpredictable deformation of the sealing plane caused by applying additional sealing pressure after mechanical compression, which leads to a decrease in sealing performance and stability. Furthermore, during mechanical compression sealing, the force direction of this sealing structure is mainly radial, avoiding the thinning of the explosion-proof notch 109 caused by shear force on the cover plate 107. The cover plate 107 is then subjected to tensile force, and the notch of the explosion-proof notch 109 can compensate for a certain amount of tensile deformation without changing the minimum thickness of the explosion-proof notch 109. This ensures stable valve opening and improves the safety of the battery 10.

[0050] In some embodiments of this application, the battery may have a fourth bend, a fifth bend, or more bends. It should be noted that, regardless of the number of bends, the cover plate needs to abut against the inside of the last bend and be connected to the negative current collector. Alternatively, it can be understood that the newly added bend can be set between the second and third bends. As for the function of the newly added bend, it can be set according to actual needs.

[0051] In some embodiments of this application, such as Figure 4As shown, both the third bend 1023 and the sealing element 108 are U-shaped structures. The sealing element 108 is adapted to the third bend 1023, and the raised edge of the cover plate 107 abuts against the U-shaped structure of the sealing element 108. Thus, compared to traditional S-shaped and U-shaped sealing structures, when the battery 10 is impacted, its sealing structure is compressed internally, making the gap between the third bend 1023 and the edge of the cover plate 107 tighter, and its sealing performance is not affected. However, for existing sealing structures, because the sealing force direction is consistent with the thickness direction of the cover plate 107 during sealing, and the cover plate 107 is relatively thin and has explosion-proof markings 109, the cover plate 107 is easily deformed by shear force during sealing, making the opening of the battery 10 unstable and affecting the safety of battery 10 use.

[0052] In some embodiments of this application, both the third bend 1023 and the sealing element 108 are L-shaped structures. The sealing element 108 is adapted to the third bend 1023, and a locking structure is provided on the inner side of both sides of the sealing element 108. The raised edge of the cover plate 107 abuts against the sealing element 108, and the locking structure engages with the raised edge of the cover plate 107. Thus, compared with the traditional S-shaped and U-shaped sealing structures, when the battery 10 is impacted, its sealing structure is compressed inside the battery 10, making the gap between the third bend 1023 and the edge of the cover plate 107 tighter, and its sealing performance is not affected. However, for the existing sealing structure, since the sealing force direction is consistent with the thickness direction of the cover plate 107 during sealing, and the cover plate 107 is relatively thin and has explosion-proof markings 109, the cover plate 107 is easily deformed by shear force during sealing, making the opening of the battery 10 unstable and affecting the safety of the battery 10.

[0053] In some embodiments of this application, such as Figure 1 In part A, the negative current collector 105 is connected to the housing 101. The connection between the negative current collector 105 and the housing 101 is located within the groove of the first bend 1021. Specifically, the negative current collector 105 and the housing 101 can be electrically connected by welding. Meanwhile, as... Figure 1 At part B, the convex edge of the second bend 1022 presses against the negative current collector 105, thereby making the connection between the housing 101 and the negative current collector 105 more stable.

[0054] In some embodiments of this application, such as Figure 6As shown, the negative current collector 105 includes an electrical connection structure 1051 and a welding part 1052. The welding part 1052 is connected to the cover plate 107 by welding. The electrical connection structure 1051 is a protruding structure of a preset shape. The protruding structure is in elastic contact with the cover plate 107. The preset shape can be set according to actual needs, such as an arch bridge shape. In this way, the electrical connection between the negative current collector 105 and the cover plate 107 can be better realized.

[0055] This application also provides an electrical device, wherein the electrical device includes the battery 10 provided in the above embodiments.

[0056] To better implement the battery in the embodiments of this application, based on the battery, the embodiments of this application also provide a battery manufacturing method. For the specific process, please refer to... Figure 7 The battery preparation method includes the following steps 201 to 204:

[0057] 201. A housing is provided, the housing having a receiving cavity and a first opening communicating with the receiving cavity.

[0058] For a better description of the battery manufacturing process, please refer to [reference needed]. Figures 2-4 ,against Figure 1 The diagram shows the structural changes of the central part C, which is magnified locally, specifically including C1-C3.

[0059] 202. Provide a negative collector disk and place the negative collector disk inside the receiving cavity.

[0060] 203. Bend the shell at a preset angle toward the inside of the shell at a first preset length away from the first opening to obtain an initial bending structure of the first preset length; wherein the preset angle is 90°, and the first preset length can be adjusted according to actual needs, which can be determined according to the size of the battery, the amount of core compression, etc.

[0061] 204. Grooving is performed at a predetermined position on the initial bending structure to form a sealing structure. The sealing structure includes a first bending portion and a second bending portion connected in sequence, wherein the convex edge of the second bending portion of the sealing structure abuts against the negative current collector. Specifically, the predetermined position can be at a distance of at least twice the bending radius.

[0062] The battery prepared by the above-described battery preparation method in this application, compared with traditional batteries, has its convex edge of the second bend of the sealing structure abutting against the negative current collector, optimizing the structural relationship between the existing sealing structure and the negative current collector. This ensures that when the battery experiences vibration and collision, the impact point does not directly interact with the sealing surface, while also having the ability to absorb a certain amount of deformation and impact force. Furthermore, it ensures sealing performance, preventing battery leakage and explosion, thereby improving battery safety.

[0063] In some embodiments of this application, the battery manufacturing method may further include: providing a cover plate, placing the cover plate inside the housing, and connecting the cover plate to the negative current collector; providing a sealing element, placing the sealing element on the raised edge of the cover plate, and mechanically pressing the sealing structure using a pre-set mold to form a third bend, so that the third bend and the cover plate are sealed.

[0064] The aforementioned seal can be L-shaped or U-shaped. If a U-shaped seal is used, the third bend needs to be bent to resemble the shape described above. Figure 4 The U-shaped structure in it.

[0065] In some embodiments of this application, before bending the housing at a preset angle at a first preset length from the first opening to obtain an initial bent structure of the first preset length, the method further includes: welding the negative current collector to the inner side of the housing; and after grooving at a preset position of the initial bent structure, the weld between the negative current collector and the inner side of the housing is located within the groove of the first bent portion. This improves the stability and safety of the welding between the negative current collector and the housing.

[0066] It should be noted that the relevant structure of the battery manufactured by the manufacturing method provided in the above embodiments can be found in the batteries provided in the foregoing embodiments, and will not be repeated here.

[0067] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A battery, characterized in that, include: The housing has a receiving cavity and a first opening communicating with the receiving cavity. The housing has a sealing structure extending radially on one side of the first opening. The sealing structure includes a first bend and a second bend that are sequentially connected from the sidewall of the housing toward the receiving cavity. A negative collector disk is built into the receiving cavity, and the convex edge of the second bent portion abuts against the negative collector disk. The first bending portion is bent along a first direction, and the second bending portion is bent along a second direction; the first direction is parallel to the axial direction of the housing; the first direction and the second direction are opposite in orientation.

2. The battery according to claim 1, characterized in that, The battery also includes a cover plate, and the sealing structure also includes a third bend, which is connected to the second bend. The cover plate abuts against the inner side of the third bend and is connected to the negative current collector.

3. The battery according to claim 2, characterized in that, The cover plate has at least one explosion-proof groove.

4. The battery according to claim 2, characterized in that, The battery also includes a seal located at the junction of the cover plate and the third bend, the seal being used to seal the cover plate and the third bend.

5. The battery according to claim 4, characterized in that, Both the third bend and the seal are U-shaped structures. The seal is adapted to the third bend, and the raised edge of the cover plate abuts against the U-shaped structure of the seal.

6. The battery according to claim 4, characterized in that, Both the third bend and the seal are L-shaped structures. The seal is adapted to the third bend. The inner sides of both sides of the seal are provided with a locking structure. The raised edge of the cover plate abuts against the seal. The locking structure locks into the raised edge of the cover plate.

7. The battery according to any one of claims 1-6, characterized in that, The negative collector is connected to the housing, and the connection between the negative collector and the housing is located in the groove of the first bend.

8. The battery according to any one of claims 2-6, characterized in that, The negative current collector includes an electrical connection structure, which is a protrusion structure of a preset shape, and the protrusion structure is in elastic contact with the cover plate.

9. The battery according to any one of claims 1-6, characterized in that, The battery also includes an electrode assembly, which is built into the receiving cavity. The electrode assembly includes a core, and the negative current collector is connected to the core. The convex edge of the second bend abuts against the side of the negative current collector away from the core.

10. The battery according to claim 9, characterized in that, The convex edge of the second bend is in tight contact with the negative collector disk.

11. A method for preparing a battery, characterized in that, The method includes: A housing is provided, the housing having a receiving cavity and a first opening communicating with the receiving cavity; A negative collector disk is provided, and the negative collector disk is built into the receiving cavity; The shell is bent inward at a preset angle at a first preset length from the first opening to obtain an initial bent structure of the first preset length. Grooving is performed at a preset position of the initial bending structure to form a sealing structure extending radially. The sealing structure includes a first bending portion and a second bending portion connected sequentially from the side wall of the housing to the receiving cavity side, wherein the convex edge of the second bending portion of the sealing structure abuts against the negative flow collector. The first bending portion is bent along a first direction, and the second bending portion is bent along a second direction; the first direction is parallel to the axial direction of the housing; the first direction and the second direction are opposite in orientation.

12. The battery preparation method according to claim 11, characterized in that, The method further includes: A cover plate is provided, which is disposed inside the housing and connected to the negative collector plate; A sealing element is provided and placed on the raised edge of the cover plate. The sealing structure is mechanically pressed together using a pre-set mold to form a third bend, so that the third bend and the cover plate are sealed.

13. The battery manufacturing method according to claim 11 or 12, characterized in that, Before bending the shell at a preset angle inward at a first preset length from the first opening to obtain the initial bent structure of the first preset length, the method further includes: The negative current collector is welded to the inner side of the housing; After grooving is performed at the preset position of the initial bending structure, the weld between the negative current collector and the inner side of the housing is located in the groove of the first bending part.

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