Battery cell and battery thereof
By setting an adhesive and separator inside the cell for fixation, combined with outer aluminum-plastic film encapsulation, the problem of structural misalignment and tearing of lithium-ion battery cells under external impact is solved, thereby improving the stability and sealing of the cell.
Patent Information
- Application Number
- CN202520271287.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-19
- Publication Date
- 2025-12-30
- Estimated Expiration
- 2035-02-19
AI Technical Summary
Existing lithium-ion battery cells are prone to internal structural misalignment and foil tearing under external impact, resulting in poor contact. Furthermore, with the increasing demand for thin-film batteries and high energy density, the problem of uneven fixing force becomes more serious.
Multiple first adhesives are placed in the empty foil areas of copper or aluminum foil inside the battery cell to bond and fix them to the separator, thereby enhancing the overall structural strength of the battery cell. An aluminum-plastic film is placed on the outside to bond with the battery cell body, forming a stable encapsulation.
This improves the overall structural strength of the battery cell, reduces the risk of internal structural misalignment and deformation under external impact, and ensures the stability and sealing of the battery cell.
Smart Images
Figure CN223743764U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates generally to the field of energy storage technology. More specifically, the present disclosure relates to an electric cell and a battery thereof. BACKGROUND
[0002] In the field of lithium ion batteries, a lithium ion battery is generally composed of a positive electrode assembly, a negative electrode assembly, and a separator disposed between the positive electrode material and the negative electrode material. Among them, the positive electrode assembly generally uses aluminum foil or the like as the current collector, and the negative electrode assembly uses copper foil or the like as the current collector. The positive electrode assembly, the separator, and the negative electrode assembly are sequentially stacked and fixed into an electric cell body by winding or adhesive tape bonding. In such an electric cell structure, since the adhesive tape is mostly disposed on the outside of the electric cell body, the winding layers of the positive electrode assembly, the negative electrode assembly, and the separator are stacked but lack fixation in the inside of the electric cell body. Therefore, when the electric cell is impacted by external forces, the inside and outside of the electric cell body may be misaligned, resulting in poor contact between the inside and outside of the electric cell body, and even causing the foil to tear.
[0003] Therefore, there is an urgent need to provide an electric cell scheme to enhance the overall structural strength of the battery cell and reduce the probability of deformation under the action of external impact forces. CONTENT OF THE INVENTION
[0004] In order to at least solve one or more of the above-mentioned technical problems, the present disclosure proposes an electric cell and a battery thereof in various aspects.
[0005] In a first aspect, the present disclosure provides an electric cell, comprising: stacked aluminum foil, positive electrode material layer, separator, negative electrode material layer and copper foil, the aluminum foil, positive electrode material layer, separator, negative electrode material layer and copper foil are wound to form an electric cell body after stacking, and the copper foil and / or aluminum foil comprises an inner extension segment located on the radial inside of the electric cell body, the inner extension segment is provided with a hollow foil area, and a plurality of first adhesive bodies are arranged on the surface of the inner extension segment, the plurality of first adhesive bodies are adhered and fixed with the separator, and fill at least part of the hollow foil area.
[0006] In some embodiments, the first adhesive body is in the shape of a dot, and the diameter of the first adhesive body is 0.3mm-1.5mm.
[0007] In some embodiments, the first adhesive body is arranged in an array, wherein the pitch of each row and / or each column of adjacent first adhesive bodies is 1.0mm-2.5mm.
[0008] In some embodiments, the height of the first adhesive body relative to the surface of the inner extension segment is 10um-60um.
[0009] In some embodiments, an aluminum plastic film is further included, the outer side surface of the battery cell body is provided with a plurality of second adhesive bodies, the plurality of second adhesive bodies are adhesively fixed with the aluminum plastic film, and the first adhesive bodies and the second adhesive bodies are hot melt adhesives.
[0010] In some embodiments, the aluminum foil includes an extension segment located at the radial outer side of the battery cell body, a plurality of third adhesive bodies are arranged between the surface of the extension segment and the separator, and the plurality of third adhesive bodies are adhesively fixed with the separator.
[0011] In some embodiments, a plurality of first adhesive body arrangement regions are arranged at intervals in the empty foil area on both sides of the extension segment of the aluminum foil and / or the copper foil.
[0012] In some embodiments, two first adhesive body arrangement regions are arranged in the empty foil area on both sides of the extension segment of the aluminum foil and / or the copper foil, respectively.
[0013] In some embodiments, the arrangement area of the first adhesive bodies accounts for 60-90% of the area of the empty foil area.
[0014] In a second aspect, the present disclosure provides a battery comprising the battery cell according to the first aspect and the plurality of embodiments.
[0015] Through the battery cell and the battery thereof provided above, the embodiments of the present disclosure can improve the overall structural strength of the battery cell and reduce the risk of structural dislocation of the battery cell when subjected to external force impact by arranging a plurality of first adhesive bodies on the empty foil area of the copper foil or the aluminum foil inside the battery cell body and adhesively fixing the plurality of first adhesive bodies with the separator. BRIEF DESCRIPTION OF DRAWINGS
[0016] The above and other objects, features and advantages of the exemplary embodiments of the present disclosure will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which several embodiments of the present disclosure are shown by way of example, and wherein like reference numerals refer to like elements throughout. In the drawings:
[0017] Figure 1a Exemplary front views of some existing battery cells are shown;
[0018] Figure 1b Rear views of some existing battery cells are shown;
[0019] Figure 2 Exemplary cross-sectional views of battery cells according to some embodiments of the present disclosure are shown;
[0020] Figure 3 A cross-sectional view of an expanded state of a positive electrode assembly of a battery cell according to some embodiments of the present disclosure is shown;
[0021] Figure 4 A cross-sectional view of an expanded state of a negative electrode assembly of a battery cell according to some embodiments of the present disclosure is shown;
[0022] Figure 5 An enlarged schematic view of the empty foil region of the electric core is shown;
[0023] Figure 6 A side view schematic view of Figure 5 is shown;
[0024] Figure 7 A partial enlarged schematic view of the A portion in FIG. 1 is shown;
[0025] Figure 8 A partial enlarged schematic view of the B portion in FIG. 1 is shown;
[0026] Figure 9 An exemplary front view of the battery of some embodiments of the present disclosure is shown.
[0027] BRIEF DESCRIPTION OF DRAWINGS
[0028] 10 - aluminum foil; 100 - electric core; 101 - empty foil region; 11 - positive electrode material layer; 12 - positive electrode tab; 20 - copper foil; 200 - battery; 201 - battery frame; 21 - negative electrode material layer; 22 - negative electrode tab; 30 - separator; 41 - first adhesive body; 43 - third adhesive body. DETAILED DESCRIPTION
[0029] The technical solutions in the embodiments of the present disclosure will be apparently and completely described below with reference to the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by a person skilled in the art without creative labor fall within the protection scope of the present disclosure.
[0030] It should be understood that the terms “comprising” and “including” used in the specification and claims of the present disclosure indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.
[0031] It should also be understood that the terms used in the specification of the present disclosure are only for the purpose of describing specific embodiments, and are not intended to limit the present disclosure. As used in the specification and claims of the present disclosure, the singular forms “a,” “an,” and “the” are intended to include the plural forms, unless the context clearly indicates otherwise. It should be further understood that the term “and / or” used in the specification and claims of the present disclosure means one or more of the associated listed items as well as all possible combinations of the items.
[0032] As used in the specification and claims, the term “if’ can be interpreted as “when” or “upon” or “in response to a determination” or “in response to a detection” depending on the context. Similarly, the phrase “if it is determined” or “if [the recited condition or event] is detected” can be interpreted as meaning “upon determining” or “in response to a determining” or “upon detecting [the recited condition or event]” or “in response to a detection of [the recited condition or event]” depending on the context.
[0033] In existing lithium-ion battery cells, a positive electrode assembly, a separator, and a negative electrode assembly are often included, which are arranged in a wound or stacked form with the separator between the positive electrode assembly and the negative electrode assembly. The positive electrode assembly generally includes a positive current collector such as an aluminum foil and a positive electrode material stacked with the positive current collector, and the negative electrode assembly can include a negative current collector such as a copper foil and a negative electrode material stacked with the negative current collector. The separator is arranged between the positive electrode material and the negative electrode material for lithium ions to pass through. See, e.g., FIGS. 1A and 1B. Figure 1a and Figure 1b , Figure 1a Exemplary front views of some existing battery cells are shown in FIGS. 2A and 2B, and Figure 1b Exemplary back views of some existing battery cells are shown in FIGS. 3A and 3B. In this structure, the wound or stacked aluminum foil and copper foil serve as the main body of the internal structure of the battery cell and provide the main support. The main body of the battery cell is fixed in the stacked or wound form by pasting adhesive tape around the outer periphery of the main body or by applying adhesive around the outer periphery of the main body and wrapping the main body with an aluminum plastic film. However, for this structure, when the main body of the battery cell is impacted by an external force, the fixing force for maintaining the structure of the main body of the battery cell is mainly concentrated on the outer side of the main body, resulting in uneven distribution of the fixing force on the inner side and the outer side of the main body of the battery cell. The impact of the external force can cause misalignment of the structure on the outer side and the structure on the inner side of the main body of the battery cell. This misalignment can cause poor contact between the various components inside the battery cell, and even cause tearing of the copper foil or aluminum foil.
[0034] In addition, as the demand for energy density and long cycle life of lithium batteries increases, the battery substrate currently used in the battery is becoming thinner and thinner, and the liquid retention amount and coefficient are becoming higher and higher. This further increases the mass ratio of the materials inside the main body of the battery, and the fixing force on the inner side and the outer side of the main body of the battery cell is more unbalanced, increasing the difficulty of fixing the structure of the main body of the battery.
[0035] Therefore, the present disclosure provides a battery cell that can improve the overall structural strength of the battery cell and reduce the risk of misalignment of the internal structure of the battery cell when impacted by an external force by providing a plurality of first adhesive bodies on the hollow foil area of the copper foil or aluminum foil inside the main body of the battery cell and fixing the plurality of first adhesive bodies with the separator.
[0036] The specific embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.
[0037] Referring also to Figure 2 and Figure 5 , Figure 2 An exemplary cross-sectional view of an electric cell is shown to illustrate some embodiments of the present disclosure, Figure 5 An enlarged schematic view of a hollow foil region of an electric cell is shown to illustrate some embodiments of the present disclosure. The electric cell 100 comprises an aluminum foil 10, a positive electrode material layer 11, a separator 30, a negative electrode material layer 21, and a copper foil 20, which are laminated and wound to form an electric cell body, and the copper foil 20 and / or the aluminum foil 10 comprises an inner extension located radially inside the electric cell body, the inner extension is provided with a hollow foil region 101, and the surface of the inner extension is further provided with a plurality of first adhesive bodies 41 arranged at intervals, the plurality of first adhesive bodies 41 are adhesively fixed with the separator 30 and fill at least part of the hollow foil region 101. Thus, after winding, the separator 30 of the axial center portion of the electric cell is fixedly connected with the copper foil 20 and / or the aluminum foil 10, the overall structural strength is improved, and the probability of structural misalignment caused by axial displacement deformation due to external impact is reduced.
[0038] In particular, referring also to Figures 2 to 4 , Figure 3 A cross-sectional view of an expanded state of a positive electrode assembly of an electric cell is shown to illustrate some embodiments of the present disclosure, and Figure 4 A cross-sectional view of an expanded state of a negative electrode assembly of an electric cell is shown to illustrate some embodiments of the present disclosure. As shown in the figure, the positive electrode assembly comprises an aluminum foil 10 and a positive electrode material layer 11 coated on both sides of the aluminum foil 10, and a positive electrode tab 12 arranged at an extension end of the aluminum foil 10 not covered by the positive electrode material layer 11. Similarly, the negative electrode assembly comprises a copper foil 20 and a negative electrode material layer 21 coated on both sides of the copper foil 20, and a negative electrode tab 22 arranged at an extension end of the copper foil 20 not covered by the negative electrode material layer 21. The positive electrode material is a mixture mainly composed of common positive electrode materials such as lithium cobaltate and ternary materials, and the negative electrode material is a mixture mainly composed of common negative electrode materials such as graphite. Thus, the positive electrode assembly and the negative electrode assembly both have a certain flexibility, so that they can be wound into a shape.
[0039] When winding the battery cell body, the negative electrode assembly is placed between two layers of separators 30, and the positive electrode assembly, the two layers of separators 30, and the negative electrode assembly are stacked together and wound into a whole, thus forming the battery cell body as shown in Figure 1. The positive electrode tab 12 and the negative electrode tab 22 extend from one side of the battery cell body for electrical connection with other conductive components such as busbars. All positive electrode material layers 11 and negative electrode material layers 21 are separated by separators 30 to facilitate chemical-electrical energy conversion. At least one end of the copper foil 20 has an empty foil area 101 not covered by the negative electrode material, and at least one end of the aluminum foil 10 has an empty foil area 101 not covered by the positive electrode material. The empty foil areas 101 of the aluminum foil 10 and the copper foil 20 are located on the surfaces of the copper foil 20 or the aluminum foil 10 that are not covered by the corresponding positive or negative electrode materials, and the first adhesive 41 is disposed in the empty foil area 101.
[0040] See also Figure 3 and Figure 5 , Figure 6 , Figure 6 It shows Figure 5 A side view schematic diagram. In the wound positive electrode assembly, the end of the copper foil 20 near the radially inner side of the cell body is set as an inner extension section. The inner extension section has an empty foil area 101 without positive electrode material. One or both sides of the empty foil area 101 are used to set a plurality of spaced first adhesives 41. The first adhesives 41 are adhesives such as hot melt adhesives, which are set in the empty foil area 101 by means of dispensing or the like for bonding with the separator 30. When the first adhesives 41 are heat-sensitive adhesives, after the cell body is wound to form, the first adhesives 41 can be activated when the cell body is heated on both sides, thereby forming a connection inside the cell body or between the cell body and the aluminum-plastic film. Moreover, its processing procedure is simple, its structure is reliable, and it is suitable for mass production of cells.
[0041] In this embodiment, the first adhesive body 41 and the second adhesive body are both hot melt adhesive. Each first adhesive body 41 is formed in a dot shape, and the diameter D1 of the first adhesive body 41 is 0.3mm-1.5mm. The first adhesive body 41 is formed into a uniform circular adhesive area after being bonded with the separator 30, thereby saving the adhesive material while ensuring the strength of the bonding. The plurality of first adhesive bodies 41 are arranged in an array, and the spacing D2 between each row and / or each column of adjacent first adhesive bodies 41 is 1.0mm-2.5mm. Thus, the first adhesive body 41 and the second adhesive body can form a plurality of stable and uniformly arranged adhesive points after bonding, thereby improving the uniformity of the bonding and avoiding excessive or insufficient local bonding force that affects the overall structural stability. The height H1 of the first adhesive body 41 relative to the inner extension surface is 10um-60um, thereby ensuring the stability of the bonding while having a lower impact on the size and structure of the battery body, which is suitable for reducing the overall size and weight of the battery, making the structure of the battery more compact and lightweight. In addition, in the empty foil area 101, the arrangement area of the first adhesive body 41 accounts for 60-90% of the area of the empty foil area 101. This ensures the bonding strength and prevents material waste or overflow of the adhesive material.
[0042] Referring to Figure 2 and Figure 7 , Figure 7 A partial enlarged view of part A of FIG. 1 is shown. In this embodiment, two first adhesive body 41 arrangement areas are respectively arranged in the empty foil areas 101 on both sides of the inner extension of the copper foil 20. Thus, after winding and forming, the first adhesive body 41 can form fixed connections with the separator 30 at different positions inside the axial direction of the battery body, thereby further enhancing the overall structural strength of each part of the battery body and reducing the probability of axial movement and deformation of the battery core caused by external force impact. Further referring to FIG. 1 and Figure 8 , Figure 8 A partial enlarged view of part B of FIG. 1 is shown. In this embodiment, four first adhesive body 41 arrangement areas are arranged at intervals on both sides of the inner extension of the aluminum foil 10, thereby further enhancing the bonding effect and improving the structural strength.
[0043] In addition, an aluminum plastic film is also arranged outside the battery body, and a plurality of second adhesive bodies are arranged on the outer surface of the battery body. The aluminum plastic film encapsulates and protects the battery body as a whole, and the second adhesive bodies tightly bond the aluminum plastic film and the battery body. The shape, structure and arrangement of the second adhesive bodies are the same as those of the first adhesive body 41, and will not be described here. The aluminum plastic film encapsulates the battery as a whole, thereby improving the structural strength of the battery and further reducing the risk of deformation of the battery body structure caused by external force.
[0044] Referring to FIG. 1 again, in this embodiment, the aluminum foil 10 is also provided with an extension section near one end of the radial outer side of the battery cell, and the extension section also includes the empty foil area 101 arranged in staggered relation to the positive electrode material. The third adhesive body 43 can be arranged in the empty foil area 101 on both sides of the extension section, and the third adhesive body 43 has the same material, size, etc. as the first adhesive body 41, which will not be described again here. The arrangement areas of the two third adhesive bodies 43 are respectively arranged on both sides of the extension section of the aluminum foil 10, and the arrangement areas of the positive electrode material layer 11 on the two side surfaces of the aluminum foil 10 are not the same, and one side of the positive electrode material layer 11 has an additional section extending toward the end of the extension section relative to the other side, which makes the areas of the empty foil areas 101 on both sides of the aluminum foil 10 on the extension section not the same. After winding and forming, the empty foil areas 101 on both sides of the extension section of the aluminum foil 10 can be bonded to the separator facing each other, and after the bonding structure is formed, the arrangement areas of the two third adhesive bodies 43 arranged in the thickness direction compensate for the missing positive electrode material part, thereby avoiding the occurrence of steps or gaps. By arranging the third adhesive body 43, the battery cell body can form a complete and closed whole, improve the overall structural strength, and improve the sealing of the battery cell. The first adhesive body 41 and the third adhesive body 43 respectively define the position of the aluminum foil relative to the separator, which also enhances the strength of the radial winding fixation as a whole and reduces the probability of radial gap. The end of the extension section of the aluminum foil 10 is directly wound and bonded to the outside of itself by means of an adhesive such as a tape to lock and seal the overall wound battery cell structure.
[0045] Those skilled in the art can understand that, although the above shows that the plurality of first adhesive bodies formed in a dot matrix are arranged in the empty foil area, and the copper foil or aluminum foil located on the radial inner side of the battery cell body is fixedly connected to the separator by means of the adhesive body, the present disclosure does not limit the specific arrangement manner and structure of the first adhesive body, as long as it can achieve the fixed strength of the copper foil and / or aluminum foil on the radial inner side of the battery cell body. For example, in some embodiments not shown, the first adhesive body is arranged in a strip shape, and a plurality of strip-shaped first adhesive bodies are arranged in the empty foil area or in the empty foil area. Or in another embodiment, the position of the empty foil area on the copper foil or aluminum foil can be arranged to have a similar number and position, or the corresponding positive or negative electrode material on one side of the copper foil or aluminum foil can be divided into a plurality of arrangement areas, and more empty foil areas are formed between the plurality of arrangement areas, and more first adhesive bodies are arranged in the corresponding empty foil areas, thereby further improving the overall structural strength. Or the copper foil and the aluminum foil are arranged to have the same or different number of empty foil areas at the above positions or other positions to adapt to various structural strength requirements, etc.
[0046] The electric cell of the plurality of embodiments of the present disclosure can set the copper foil and / or aluminum foil with the inner extension, set a plurality of first adhesive bodies on the empty foil area of the copper foil and / or aluminum foil located radially inside the main body of the electric cell, and fix the plurality of first adhesive bodies with the diaphragm, so as to ensure the compactness of the overall structure of the electric cell, improve the overall structural strength of the electric cell, and reduce the risk of dislocation of the internal structure of the electric cell when subjected to external force impact.
[0047] Referring to Figure 9 , Figure 9 An exemplary front view of a battery of some embodiments of the present disclosure is shown. In this embodiment, the battery 200 includes a plurality of electric cells 100 according to the above-described embodiments of the present disclosure, and a battery frame 201. The battery frame 201 is internally provided with a receiving cavity for receiving the plurality of electric cells 100. The plurality of electric cells 100 are fixedly arranged in the battery frame 201 and sealed by the battery frame 201, and the positive and negative electrode tabs of the plurality of electric cells 100 are respectively connected to the positive and negative terminals 211 and 212 of the battery frame 201, so as to connect the plurality of electric cells in series.
[0048] Although the plurality of embodiments of the present disclosure have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided only in an exemplary manner. Those skilled in the art can think of many changes, modifications and alternatives without departing from the idea and spirit of the present disclosure. It should be understood that various alternatives to the embodiments of the present disclosure described herein can be employed in practicing the present disclosure. The appended claims are intended to define the scope of protection of the present disclosure, and thus cover equivalent or alternative solutions within the scope of the claims.
Claims
1. An electric cell, characterized by, Comprise: The aluminum foil (10), the positive electrode material layer (11), the separator (30), the negative electrode material layer (21) and the copper foil (20) are wound to form a battery core body after being stacked, and The copper foil (20) and / or the aluminum foil (10) comprises an inner extension section located radially inside the battery core body, and a hollow foil area (101) is arranged on the inner extension section, and a plurality of first adhesive bodies (41) are also arranged on the surface of the inner extension section, the plurality of first adhesive bodies (41) are adhesively fixed with the separator (30) and fill at least part of the hollow foil area (101).
2. The electric cell of claim 1, wherein, The first adhesive body (41) is a round dot, and the diameter of the first adhesive body (41) is 0.3mm-1.5mm.
3. The electric cell of claim 2, wherein, The first adhesive body (41) is arranged in an array, and the spacing between each row and / or each column of adjacent first adhesive bodies (41) is 1.0mm-2.5mm.
4. The cell of claim 3, wherein, The height of the first adhesive body (41) relative to the surface of the inner extension section is 10um-60um.
5. The electric cell of claim 1, wherein, Further comprising an aluminum plastic film, and a plurality of second adhesive bodies are arranged on the outer surface of the battery core body, and the plurality of second adhesive bodies are adhesively fixed with the aluminum plastic film, and the first adhesive body (41) and the second adhesive body are hot melt glue.
6. The electric cell of claim 1, wherein, The aluminum foil (10) comprises an outer extension section located radially outside the battery core body, and a plurality of third adhesive bodies (43) are arranged between the surface of the outer extension section and the separator (30), and the plurality of third adhesive bodies (43) are adhesively fixed with the separator (30).
7. The electric cell of claim 1, wherein, A plurality of first adhesive body (41) arrangement areas are arranged in the hollow foil area (101) on both sides of the inner extension section of the aluminum foil (10) and / or the copper foil (20).
8. The electric cell of claim 1, wherein, Two first adhesive body (41) arrangement areas are arranged in the hollow foil area (101) on both sides of the inner extension section of the aluminum foil (10) and / or the copper foil (20).
9. The electric cell of any one of claims 1 to 8, wherein, The arrangement area of the first adhesive body (41) accounts for 60-90% of the area of the hollow foil area (101).
10. A battery, characterized by Comprise the battery core according to any one of claims 1-9.