Insulating plastic part and square lithium battery

Abstract

The utility model relates to an insulating plastic part and a square lithium battery, the insulating plastic part is arranged in an assembly gap between a top cover of the lithium battery and the end part of a roll core, the insulating plastic part comprises a base body, and at least two convex parts are arranged on the surface of the end part, facing the roll core, of the base body. A cavity is formed in each protruding part, a pushing piece is arranged in each cavity, and the pushing pieces can move in the corresponding cavities in the direction close to the end of the roll core and the direction away from the end of the roll core. The notch of each pushing piece faces the corresponding cavity, and expansion substances are arranged between the cavities and the notches of the pushing pieces. The expansion substance absorbs electrolyte in the lithium battery and then expands to push out the pushing piece, so that the pushing piece tightly abuts against the surface of the end part of the roll core, an assembly gap caused by factors such as a manufacturing process is made up, and shaking of the internal structure of the lithium battery under a vibration working condition is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of lithium battery insulation, and in particular to an insulating plastic part and a square lithium battery. Background Art

[0002] With the development of lithium-ion battery technology, the top cover and aluminum shell serve as the packaging components for the poles. To cope with the vibration conditions within the battery cell, an insulator is usually installed under the top cover to prevent shaking after the core is inserted into the shell, thereby improving the safety performance of lithium-ion batteries. However, in practice, due to the tolerance range of the core, it is difficult to accurately calculate the thickness of the insulator to meet the requirements of the press-fit effect of the core. Excessive press-fitting can damage the pole pieces of the core, while insufficient press-fitting cannot ensure the stable installation of the core. Utility Model Content

[0003] Based on this, it is necessary to provide an insulating plastic part and a square lithium battery to address the problem that the lithium battery core cannot meet the insulation pressing requirements.

[0004] An insulating plastic part is provided between the assembly gap between the top cover and the end of the winding core of the lithium battery, comprising:

[0005] A base body, wherein at least two protrusions are provided on a surface of the base body facing the end of the winding core, each protrusion having a cavity therein, and each cavity having a pusher therein, the pusher being movable in a direction approaching the end of the winding core and away from the end of the winding core within the corresponding cavity;

[0006] Each pusher is provided with a notch facing the corresponding cavity, and an expansion material is provided between the cavity and the notch of the pusher. The expansion material is used to absorb the electrolyte in the lithium battery and expand so that the pusher presses against the surface of the end of the winding core.

[0007] In one embodiment, the pushing member is provided with an electrolyte hole for receiving the electrolyte.

[0008] In one embodiment, the base is configured as a rectangular plate, and the raised portion is configured as a rectangular raised block.

[0009] In one embodiment, the length of the base body is consistent with the length of the assembly gap.

[0010] In one embodiment, the protrusions are symmetrically arranged at both ends of the base, and the same pushing members and expansion materials are arranged in the protrusions on both sides.

[0011] In one embodiment, the thickness of each protrusion is uniform and greater than the thickness of the base.

[0012] In one embodiment, the width of the base is consistent with the width of the assembly gap, and the width of the protrusion is less than or equal to the width of the base.

[0013] In one embodiment, the base body is provided as a one-piece injection-molded part.

[0014] In one embodiment, the expansion material is provided as an expansion strip.

[0015] A square lithium battery comprises a top cover, a winding core and an aluminum shell assembled with each other, including any of the above insulating plastic parts.

[0016] The insulating plastic part is positioned between the assembly gap between the top cover and the end of the reel of the lithium battery. The insulating plastic part includes a base, and the surface of the base facing the end of the reel is provided with a protrusion, and there are at least two protrusions. Each protrusion is provided within a cavity, and each cavity is provided with a pusher. The pusher can move within the corresponding cavity in a direction close to the end of the reel and away from the end of the reel. The notch of each pusher is provided facing the corresponding cavity, and an expansion material is provided between the cavity and the notch of the pusher. The expansion material expands within the notch, thereby pushing the pusher from the inside out. The notch arrangement ensures that the expansion material fully contacts and pushes the pusher during the expansion process. After absorbing the electrolyte in the lithium battery, the expansion material expands, pushing the pusher in a direction close to the end of the reel, so that the pusher presses against the surface of the end of the reel, compensating for the assembly gap caused by factors such as the manufacturing process, and preventing the internal structure of the lithium battery from shaking under vibration conditions.

[0017] A square lithium battery includes the above-mentioned insulating plastic part and has the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the assembly of an insulating plastic part provided in an embodiment of the present application.

[0019] Figure 2 This is a schematic diagram of the assembly of an insulating plastic part provided in an embodiment of the present application from another perspective.

[0020] Figure 3 for Figure 1 Bottom view of the .

[0021] Figure 4 for Figure 1 side view.

[0022] Figure 5 This is a schematic diagram of the assembly of an insulating plastic part and a lithium battery provided in an embodiment of the present application.

[0023] Figure Number:

[0024] 1-top cover, 2-winding core, 3-base, 4-protrusion, 5-cavity, 6-pushing member, 7-electrolyte hole, 8-aluminum shell. DETAILED DESCRIPTION

[0025] To make the above-mentioned objects, features, and advantages of the present application more clearly understood, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings. The following description sets forth many specific details to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0026] In the description of this application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0027] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include at least one of such features. In the description of this application, if the term "plurality" appears, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined.

[0028] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connected," "fixed," etc., should be interpreted broadly. For example, these terms may refer to fixed connections, removable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediary; and internal communication between two components or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0029] In this application, unless otherwise expressly specified or limited, if a first feature is described as being "above" or "below" a second feature, or similar descriptions, this may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is described as being "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is described as being "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0030] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only embodiment.

[0031] See Figures 1-4 As shown, Figure 1 This is a schematic diagram of an assembly of an insulating plastic part provided in an embodiment of the present application. Figure 2 A schematic diagram of an assembly of an insulating plastic part provided in an embodiment of the present application from another perspective, Figure 3 for Figure 1 Bottom view of Figure 4 for Figure 1 A side view of an insulating plastic component is shown. The insulating plastic component is disposed between the assembly gap between the top cover 1 and the end of the winding core 2 of the lithium battery. The insulating plastic component includes a base 3. The surface of the base 3 facing the end of the winding core 2 is provided with a protrusion 4, and there are at least two protrusions 4. Each protrusion 4 is provided within a cavity 5, and each cavity 5 is provided within a pusher 6. The pusher 6 can move within the corresponding cavity 5 in a direction toward and away from the end of the winding core 2.

[0032] Each pusher 6 is provided with a notch facing the corresponding cavity 5, and an expansion material is provided between the cavity 5 and the notch of the pusher 6. The expansion material expands within the notch, thereby pushing the pusher 6 from the inside out. The notch arrangement ensures that the expansion material fully contacts and pushes the pusher 6 during the expansion process.

[0033] The expanding material will expand after absorbing the electrolyte in the lithium battery, pushing the pusher 6 in the direction close to the end of the winding core 2, so that the pusher 6 presses against the surface of the end of the winding core 2, filling the assembly gap and preventing the top cover 1 and the winding core 2 from shaking relative to each other.

[0034] During actual assembly, first place the insulating plastic part between the top cover 1 and the assembly gap at the end of the core 2, then connect the pole on the top cover 1 to the core 2, and finally place the entire structure into the aluminum shell 8. After assembly is completed, the electrolyte in the lithium battery will enter the cavity 5, and the expanding material in the cavity 5 will expand after absorbing the electrolyte, filling the cavity 5, and pushing the pusher 6 outward along the predetermined route in the cavity 5. The pushed-out pusher 6 will inevitably press against the end face of the end of the core 2, thereby fully pressing the core 2. At the same time, the base 3 will also press against the top cover 1 in the opposite direction to make up for the assembly gap caused by factors such as the manufacturing process, and avoid shaking of the internal structure of the lithium battery caused by vibration conditions. The present application provides a lithium battery that first assembles the top cover 1 and the core 2 and then makes up for the assembly gap. Such a setting can adaptively fill the fitting gap under different tolerances and the specific press-fit height cannot be determined after the core 2 is positioned. After applying this insulating plastic part, the height of the lithium battery core 2 can be optimized to a certain extent, thereby reducing the difficulty of packaging the core 2 into the shell. The gap filling achieved by the expansion material and the pusher 6 can ensure stable support without causing any damage to the top cover 1 and the core 2. Excessive pressure will be buffered by the expansion material, avoiding abnormal flatness of the top cover 1 due to excessive internal pressure, thereby ensuring packaging reliability.

[0035] The above-mentioned expansion material is selected from a material that does not react with the electrolyte, and the expansion effect of the expansion material after absorbing the liquid is irreversible. The specific selection of the expansion material can refer to the existing technology according to actual needs and will not be repeated in this article.

[0036] There are at least two and not limited to two raised portions 4, each of which is equipped with the above-mentioned pusher 6 and expansion material. The use principle of the electrolyte absorption and pushing-out pusher 6 in each raised portion 4 is consistent. By controlling the number, position and size of the raised portions 4, the strength of the pressing of the core 2 can be adjusted, and can be adaptively adjusted according to actual conditions.

[0037] The specific structure of the pushing member can be adaptively changed according to actual needs. It only needs to be pushed by the expanding material along the guiding direction of the cavity 5 to the end surface of the tight winding core 2. It will not be described in detail herein.

[0038] In one embodiment of the present application, the pusher 6 is provided with an electrolyte hole 7 for receiving electrolyte. The electrolyte hole 7 is provided on the surface of the pusher 6 facing the end of the winding core 2. The electrolyte hole 7 only needs to allow the electrolyte in the lithium battery to naturally flow into the cavity 5 and come into contact with the expansion material. The size, location, and number of the electrolyte holes 7 can be modified according to actual needs and will not be further described here.

[0039] In one embodiment of the present application, the above-mentioned base 3 is set as a rectangular plate, and the raised portion 4 is set as a rectangular raised block. The long side of the rectangular plate is equal to the length of the assembly gap, and the wide side of the rectangular plate is equal to the width of the assembly gap. After being set as a rectangle, it is easier for the base 3 to adapt to fill the assembly gap. Similarly, the rectangular raised block is also easier to define the length and width. Among them, the width and length referred to are determined by the assembly gap in the conventional lithium battery structure, that is, assuming that when the ends of the top cover 1 and the core 2 are set to rectangles, the length and width are determined by the shape of the top cover 1 and the core 2, and the insulating plastic part can be adaptively designed in accordance with the length and width. Similarly, the assembly gap is ultimately reflected as a rectangle or an irregular shape and does not affect the size of the base 3, which is adaptively set according to the width and length defined by the top cover 1 and the core 2.

[0040] In one embodiment of the present application, the length of the base 3 is consistent with the length of the assembly gap, thereby preventing the base 3 from shaking in the assembly gap along the length direction.

[0041] In one embodiment of the present application, the aforementioned raised portions 4 are symmetrically positioned at both ends of the base 3, and both raised portions 4 contain identical pushers 6 and expansion materials. The symmetrical placement of the raised portions 4 on both sides facilitates balanced support of the insulating plastic component within the assembly gap, avoiding the issue of the pusher 6 on one side being fully positioned while the pusher 6 on the other side has insufficient travel. Two raised portions 4 represent the minimum number of raised portions 4 required on the base 3, ensuring a simple structure for the insulating plastic component, simplifying production and reducing costs.

[0042] In one embodiment of the present application, each of the protrusions 4 has a uniform thickness and is greater than the thickness of the base 3. The thickness of each protrusion 4 determines the smoothness with which the insulating plastic component is pre-installed into the assembly gap, preventing skew during the initial installation phase. Furthermore, the cavity 5 within the protrusions 4 is uniformly sized, and the movable travel of the pusher 6 is uniform to ensure consistent filling.

[0043] In one embodiment of the present application, the width of the base 3 is consistent with the width of the assembly gap, preventing the base 3 from shaking within the assembly gap along the width direction. Furthermore, the width of the protrusion 4 is less than or equal to the width of the base 3, ensuring that the protrusion 4 is placed on the base 3 while meeting the assembly requirements of the base 3.

[0044] In one embodiment of the present application, the base body 3 is integrally injection molded to ensure the structural strength of the structure, simplify the process flow, and set the pusher 6 and the expansion material as replaceable devices.

[0045] In one embodiment of the present application, the aforementioned expansion material is configured as an expansion strip. The expansion strip offers the advantages of easy replacement and excellent expansion performance. In one embodiment of the present application, after integral injection molding of the base 3, a cavity 5 is formed on the raised portion 4. The opening of the cavity 5 faces away from the base 3 relative to the raised portion 4. An expansion strip is placed within the cavity 5, and a corresponding pusher 6 is installed. Before the lithium battery is assembled, the expansion strip is in a contracted state, with most or all of the pusher 6 located within the cavity 5. Subsequently, the insulating plastic component is inserted between the top cover 1 and the winding core 2. The top cover 1 and winding core 2 are positioned integrally according to conventional lithium battery assembly methods and then placed within the aluminum shell 8. The electrolyte within the lithium battery enters the expansion strip through the electrolyte hole 7. The expansion strip absorbs the electrolyte, expands, and pushes out the pusher 6. The pusher 6 pushes outward until it presses against the end face of the winding core 2. At this point, the top cover 1 is fully encapsulated. Once the expansion strip has absorbed sufficient electrolyte, the winding core 2 is fully compressed and positioned, and any excess internal pressure is borne by the expansion strip. In the assembly space between the top cover 1 and the winding core 2 , the base 2 presses against the surface of the top cover 1 facing the winding core 2 , and the pushing member 6 presses against the end surface of the winding core 2 .

[0046] Reference Attachment Figure 5 , Figure 5 This is a schematic diagram of the assembly of an insulating plastic component and a lithium battery provided in an embodiment of the present application. The diagram includes a prismatic lithium battery comprising a top cover 1, a winding core 2, and an aluminum shell 8, which are assembled together. The insulating plastic component is assembled within the rectangular assembly gap between the top cover 1 and the winding core 2.

[0047] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0048] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. An insulating plastic part, used to be arranged between the assembly gap between the top cover and the end of the winding core of a lithium battery, characterized in that: include: a base body, wherein at least two protrusions are provided on a surface of the base body facing the end of the winding core, each of the protrusions is provided with a cavity, each of the cavities is provided with a pusher, and the pusher can move in the corresponding cavity in a direction close to and away from the end of the winding core; Each of the pushing members is provided with a notch facing the corresponding cavity, and an expansion material is provided between the cavity and the notch of the pushing member. The expansion material is used to absorb the electrolyte in the lithium battery and expand so that the pushing member presses against the surface of the end of the winding core.

2. The insulating plastic part according to claim 1, wherein: The pushing member is provided with an electrolyte hole for receiving the electrolyte.

3. The insulating plastic part according to claim 1, wherein: The base is configured as a rectangular plate, and the raised portion is configured as a rectangular raised block.

4. The insulating plastic part according to claim 1, wherein: The length of the base body is consistent with the length of the assembly gap.

5. The insulating plastic part according to claim 1, wherein: The protrusions are symmetrically arranged at both ends of the base, and the same pushing members and the expansion material are arranged in the protrusions on both sides.

6. The insulating plastic part according to claim 1, wherein: The thickness of each protrusion is consistent and greater than the thickness of the base.

7. The insulating plastic part according to claim 1, wherein: The width of the base is consistent with the width of the assembly gap, and the width of the protrusion is less than or equal to the width of the base.

8. The insulating plastic part according to claim 1, wherein: The base body is provided as an integral injection-molded part.

9. The insulating plastic part according to claim 1, wherein: The expansion material is configured as an expansion strip.

10. A square lithium battery, comprising the top cover, the winding core and the aluminum shell assembled with each other, characterized in that: The insulating plastic part comprises any one of claims 1 to 9.

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