Battery cell and battery

Abstract

The embodiment of the utility model provides a kind of electric core and battery, it is related to battery technical field, to optimize electric core structure to some extent, improve the bonding reliability between roll core and aluminum plastic film, simultaneously, improve the flexibility of adhesive layer design, realize the possibility of increasing roll core volume to improve energy density.The electric core provided in the application comprises pole piece, adhesive layer and aluminum plastic film;Aluminum plastic film is formed with accommodating space, pole piece is wound to form roll core, roll core is arranged in the accommodating space of aluminum plastic film, the first surface and the second surface of roll core and aluminum plastic film are both coated with adhesive layer, and the adhesive layer is bonded with aluminum plastic film by hot-pressing process.

Description

Technical Field

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

[0002] With the rapid development of portable electronic devices and new energy vehicles, lithium-ion batteries have become an indispensable energy storage device in modern society due to their high energy density and long cycle life. As one of the mainstream types of lithium-ion batteries, the wound battery typically consists of a core formed by winding electrode sheets, an aluminum-plastic film wrapping the core, and an outer protective shell. In existing production processes, to ensure the relative position between the core and the aluminum-plastic film is fixed, pre-formed double-sided adhesive is commonly used for bonding. This bonding method relies on the physical properties of the double-sided adhesive to achieve a mechanical connection.

[0003] In current technology, double-sided adhesive tape, as a standard industrial component, has fixed thickness and width parameters. This rigid specification leads to significant limitations in practical applications. On the one hand, when the core experiences dimensional fluctuations due to charge-discharge cycles or manufacturing tolerances, the fixed-size double-sided adhesive tape cannot effectively compensate for changes in the gap between the core and the aluminum-plastic film, easily leading to the risk of adhesive failure. On the other hand, during the battery design phase, the internal space of the casing and the thickness of the double-sided adhesive form a rigid matching relationship, forcing the core thickness design to prioritize the installation requirements of the double-sided adhesive. This design constraint directly limits the possibility of increasing energy density by increasing the core volume. Furthermore, the elastic modulus and deformation capacity of the double-sided adhesive cannot adapt to the expansion and contraction of the core during battery operation, further exacerbating the risk of interface separation.

[0004] Therefore, there is an urgent need to provide a cell and battery to address the problems existing in the current technology to some extent. Utility Model Content

[0005] The purpose of this utility model is to provide a battery cell that can optimize the battery cell structure to a certain extent, improve the bonding reliability between the core and the aluminum-plastic film, and at the same time improve the flexibility of the adhesive layer design, realizing the possibility of increasing energy density by increasing the core volume.

[0006] The embodiments of this utility model can be implemented as follows: The battery cell provided in this application includes an electrode sheet, an adhesive layer, and an aluminum-plastic film; the aluminum-plastic film forms a receiving space, the electrode sheet is wound to form a core, the core is disposed within the receiving space of the aluminum-plastic film, and the adhesive layer is coated on both the first and second surfaces of the core that are in contact with the aluminum-plastic film, and the adhesive layer is bonded to the aluminum-plastic film by a hot pressing process.

[0007] The adhesive layer on the first surface of the core includes a first adhesive layer and a second adhesive layer, with the first adhesive layer and the second adhesive layer spaced apart.

[0008] Specifically, the first adhesive layer and the second adhesive layer have the same shape and area.

[0009] Specifically, the first adhesive layer and the second adhesive layer are rectangular, circular, polygonal, or irregular in shape.

[0010] The adhesive layer on the second surface of the core includes a third adhesive layer and a fourth adhesive layer, and the third adhesive layer and the fourth adhesive layer are spaced apart.

[0011] Specifically, the third adhesive layer and the fourth adhesive layer have the same shape and area, and the shape and area of ​​the third adhesive layer and the fourth adhesive layer are the same as those of the first adhesive layer and the second adhesive layer.

[0012] Specifically, the third adhesive layer and the fourth adhesive layer are rectangular, circular, polygonal, or irregular in shape.

[0013] Specifically, the third adhesive layer and the first adhesive layer are disposed opposite to each other in the thickness direction of the core, and the fourth adhesive layer and the second adhesive layer are disposed opposite to each other in the thickness direction of the core.

[0014] Furthermore, the winding core provided in this application also includes a positive electrode and a negative electrode, the positive electrode and the negative electrode being wound inside the winding core, and the positive electrode and the negative electrode extending out on the same side of the winding core.

[0015] Compared with the prior art, the battery cell provided in this embodiment of the present invention has the following advantages: The battery cell provided in this application includes an electrode sheet, an adhesive layer, and an aluminum-plastic film. The aluminum-plastic film has a receiving space, the electrode sheet is wound to form a core, the core is placed in the receiving space of the aluminum-plastic film, and the first and second surfaces of the core that are in contact with the aluminum-plastic film are coated with an adhesive layer. The adhesive layer is bonded to the aluminum-plastic film by a hot pressing process.

[0016] Analysis shows that a core can be formed by winding the electrode sheet, and an adhesive layer can be applied to the first and second surfaces of the formed core for bonding the core to the aluminum-plastic film. In actual operation, the electrode sheet is first wound to form a core, then an adhesive layer is applied to the first and second surfaces of the core. Finally, the aluminum-plastic film is wrapped around the core after the adhesive layer is applied, and hot pressing is used to melt the adhesive layer, thereby achieving a tight bond between the aluminum-plastic film and the core. The aluminum-plastic film and core bonded by coating and hot pressing have a tighter bonding effect.

[0017] Furthermore, since the adhesive layer in this application is formed by coating, its size and thickness can be flexibly designed according to specific circumstances. For example, reducing the adhesive layer thickness allows for the further winding of a certain number of electrode layers, thereby enabling the core to achieve a relatively larger volume and increasing energy density. Moreover, when the width or length of the core needs to be changed, the coated adhesive layer can be applied adaptively according to the width or length of the core, thus ensuring a more stable bond between the core and the aluminum-plastic film.

[0018] In addition, this application also provides a battery using the above-mentioned battery cell.

[0019] Batteries using the cells provided in this application can flexibly adjust the state of the adhesive layer according to specific needs, thereby enabling the increase of energy density by increasing the core volume, and also providing more stable connection stability between the core and the aluminum-plastic film. Attached Figure Description

[0020] 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.

[0021] Figure 1 This is a schematic diagram showing the location of the adhesive layer in the battery cell provided in this embodiment; Figure 2 This is an end face view of the wound core in the battery cell provided in this embodiment; Figure 3 for Figure 2 A magnified view of a section at point A in the middle; Figure 4 This is a schematic diagram of the overall structure of the battery cell provided in this embodiment.

[0022] Icons: 1-Core; 101-Adhesive layer; 1011-First adhesive layer; 1012-Second adhesive layer; 1013-Third adhesive layer; 1014-Fourth adhesive layer; 2-Positive electrode; 3-Negative electrode; 4-Aluminum-plastic film. Detailed Implementation

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0028] 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.

[0029] The following describes in detail the overall structure, working principle, and technical effects of the battery cell provided by this utility model through embodiments and in conjunction with the accompanying drawings.

[0030] like Figures 1-4 As shown, the battery cell provided in this application includes an electrode sheet, an adhesive layer 101, and an aluminum-plastic film 4. The aluminum-plastic film 4 has a receiving space, the electrode sheet is wound to form a core 1, the core 1 is disposed in the receiving space of the aluminum-plastic film 4, and the first and second surfaces of the core 1 in contact with the aluminum-plastic film 4 are coated with an adhesive layer 101. The adhesive layer 101 is bonded to the aluminum-plastic film 4 by a hot pressing process.

[0031] Compared with the prior art, the battery cell provided in this embodiment of the present invention has the following advantages: The battery cell provided in this application can be formed into a core 1 by winding electrode sheets. An adhesive layer 101 is applied to the first and second surfaces of the formed core 1 to bond the core 1 to the aluminum-plastic film 4. In actual operation, the electrode sheets are first wound to form the core 1. Then, an adhesive layer 101 is formed by coating the first and second surfaces of the core 1. Finally, the aluminum-plastic film 4 is wrapped around the core 1 after the adhesive layer 101 is applied, and the adhesive layer 101 is melted by hot pressing. This achieves a tight bond between the aluminum-plastic film 4 and the core 1. The aluminum-plastic film 4 and the core 1 bonded by coating and hot pressing have a tighter bonding effect.

[0032] Furthermore, since the adhesive layer 101 in this application is formed by coating, its size and thickness can be flexibly designed according to specific circumstances. For example, reducing the thickness of the adhesive layer 101 allows for the further winding of a certain number of electrode layers, thereby enabling the core 1 to achieve a relatively larger volume and improve energy density. Moreover, when the width or length of the core 1 needs to be changed, the coated adhesive layer 101 can be applied adaptively according to the width or length of the core 1, thereby ensuring a more stable bond between the core 1 and the aluminum-plastic film 4.

[0033] It should be noted that the coverage areas of the adhesive layer 101 on the first surface and the adhesive layer 101 on the second surface in this application may be the same or different. Preferably, based on the area of ​​the core 1, the adhesive layer 101 is formed at the center of the core 1. Taking the core 1 as a rectangle and the adhesive layer 101 as a rectangle as an example, the distance between the edge of the formed adhesive layer 101 and the edge of the core 1 is not less than 5mm.

[0034] It should be further explained here that the shape, length, width, and thickness of the adhesive layer 101 on the first surface and the adhesive layer 101 on the second surface can be the same or different. For example, the adhesive layer 101 on the first surface can be a complete rectangular adhesive layer 101, while the adhesive layer 101 on the second surface can be multiple parallel rectangular adhesive layers 101, or it can be multiple rectangular, circular, polygonal, regular, or even irregularly shaped adhesive layers 101 arranged in an array. Therefore, the shape and size of the adhesive layer 101 provided in this application can be flexibly designed, thereby enabling more flexible and varied designs for the core 1 and the overall battery.

[0035] Based on the above structure, this application provides a design method for the adhesive layer 101 in some embodiments, such as... Figures 1-3 As shown, the adhesive layer 101 on the first surface of the core 1 in this application includes a first adhesive layer 1011 and a second adhesive layer 1012, with the first adhesive layer 1011 and the second adhesive layer 1012 spaced apart.

[0036] Since the adhesive layer 101 in this application needs to be hot-pressed in the final stage to achieve the function of bonding the core 1 and the aluminum-plastic film 4 together, the coated adhesive layer 101 will expand outward to a certain extent during the hot-pressing process. By forming a first adhesive layer 1011 and a second adhesive layer 1012 spaced apart on the first surface, the excessive area overlap of the first adhesive layer 1011 and the second adhesive layer 1012 during the hot-pressing process can be reduced to a certain extent, which would cause changes in thickness and affect the stability of the bond.

[0037] Preferably, the first adhesive layer 1011 and the second adhesive layer 1012 in this application have the same shape and area.

[0038] Understandably, since coating machines typically include brush coating machines, and the simplest process for brush coating machines to apply adhesive layer 101 is by brushing adhesive in a straight line, it is possible to form a first adhesive layer 1011 and a second adhesive layer 1012 with the same shape, area and thickness, thereby ensuring the standardization of the coating process to a certain extent.

[0039] Of course, the first adhesive layer 1011 and the second adhesive layer 1012 in this application may not have a gap or may be designed so that the first adhesive layer 1011 and the second adhesive layer 1012 after hot pressing form a complete rectangular area.

[0040] Optionally, the first adhesive layer 1011 and the second adhesive layer 1012 in this application are rectangular, circular, polygonal, or irregular in shape.

[0041] The first adhesive layer 1011 and the second adhesive layer 1012 provided in this application are preferably designed to have the same shape and size, which can facilitate the operation of the coating machine. However, without considering the operation method, the shape and size of the first adhesive layer 1011 and the second adhesive layer 1012 may also be different, which will not be elaborated here.

[0042] Accordingly, the adhesive layer 101 on the second surface of the core 1 in this application includes a third adhesive layer 1013 and a fourth adhesive layer 1014, and the third adhesive layer 1013 and the fourth adhesive layer 1014 are spaced apart.

[0043] Preferably, the third adhesive layer 1013 and the fourth adhesive layer 1014 in this application have the same shape and area, and the shape and area of ​​the third adhesive layer 1013 and the fourth adhesive layer 1014 are the same as those of the first adhesive layer 1011 and the second adhesive layer 1012, thereby enabling a simpler and faster application of the adhesive layer 101.

[0044] Of course, the first adhesive layer 1011, the second adhesive layer 1012, the third adhesive layer 1013 and the fourth adhesive layer 1014 can also adopt different shapes and sizes. The design of the same shape and size is only for the sake of simplicity and convenience in actual operation. Other mating forms are also within the protection scope of this application.

[0045] Preferably, the third adhesive layer 1013 and the fourth adhesive layer 1014 in this application are rectangular, circular, polygonal, or irregular in shape.

[0046] More preferably, in this application, the third adhesive layer 1013 and the first adhesive layer 1011 are disposed opposite to each other in the thickness direction of the core 1, and the fourth adhesive layer 1014 and the second adhesive layer 1012 are disposed opposite to each other in the thickness direction of the core 1.

[0047] It is understandable that, such as Figure 4 As shown, the core 1 provided in this application also includes a positive electrode 2 and a negative electrode 3, which are wound inside the core 1 and extend from the same side of the core 1.

[0048] In addition, this application also provides a battery using the above-mentioned battery cell.

[0049] The battery using the cell provided in this application can flexibly adjust the state of the adhesive layer 101 according to specific needs, thereby realizing the means of increasing the energy density by increasing the volume of the core 1, and also providing more stable connection stability between the core 1 and the aluminum-plastic film 4.

[0050] 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 battery cell, characterized in that, Includes electrode sheets, adhesive layer, and aluminum-plastic film; The aluminum-plastic film has a receiving space, the electrode sheet is wound to form a core, the core is placed in the receiving space of the aluminum-plastic film, and the first and second surfaces of the core that are in contact with the aluminum-plastic film are coated with the adhesive layer, which is bonded to the aluminum-plastic film by a hot pressing process.

2. The battery cell according to claim 1, characterized in that, The adhesive layer on the first surface of the core includes a first adhesive layer and a second adhesive layer, with the first adhesive layer and the second adhesive layer spaced apart.

3. The battery cell according to claim 2, characterized in that, The first adhesive layer and the second adhesive layer have the same shape and area.

4. The battery cell according to claim 2, characterized in that, The first adhesive layer and the second adhesive layer are circular, polygonal, or irregular in shape.

5. The battery cell according to claim 2, characterized in that, The adhesive layer on the second surface of the core includes a third adhesive layer and a fourth adhesive layer, and the third adhesive layer and the fourth adhesive layer are spaced apart.

6. The battery cell according to claim 5, characterized in that, The third adhesive layer and the fourth adhesive layer have the same shape and area, and the shape and area of ​​the third adhesive layer and the fourth adhesive layer are the same as those of the first adhesive layer and the second adhesive layer.

7. The battery cell according to claim 5, characterized in that, The third adhesive layer and the fourth adhesive layer are circular, polygonal, or irregular in shape.

8. The battery cell according to claim 5, characterized in that, The third adhesive layer and the first adhesive layer are disposed opposite to each other in the thickness direction of the core, and the fourth adhesive layer and the second adhesive layer are disposed opposite to each other in the thickness direction of the core.

9. The battery cell according to claim 1, characterized in that, It also includes a positive electrode and a negative electrode, which are wound inside the core and extend out on the same side of the core.

10. A battery, characterized in that, The battery cell includes any one of claims 1-9 above.

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