Aluminum plastic film structure, battery cell and battery
By adding grooves and adhesive separators in the aluminum-plastic film structure, the problem of contact corrosion between the aluminum-plastic film and the anode under the compact design of the silicon negative electrode battery is solved, and the stability and safety of the battery cell are improved.
Patent Information
- Application Number
- CN202422398097.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-30
- Publication Date
- 2025-09-02
- Estimated Expiration
- 2034-09-30
AI Technical Summary
In the case of compact design of existing silicon negative electrode batteries, electrochemical corrosion is prone to occur when the aluminum-plastic film comes into contact with the anode, resulting in swelling of the battery cell and leakage of liquid. The improper use of existing protective glue leads to poor safety and stability.
A groove is added in the aluminum-plastic film structure, and an adhesive partition member is provided in the groove, including an adhesive layer and a liquid absorbing layer, for contacting the corner section of the battery core electrode sheet, preventing direct contact and reducing the use of partition green glue.
The flatness of the aluminum-plastic film structure is improved, the pole sheets are prevented from punctured by the aluminum-plastic film, the electrochemical corrosion is prevented, and the stability and safety of the battery cell are enhanced.
Smart Images
Figure CN223296922U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of batteries, and in particular relates to an aluminum-plastic film structure, a battery core and a battery. Background Art
[0002] At present, 3C products are all developing in the direction of high ED. In order to strive for a more compact design of ED battery cell structure, especially in the past two years, the development of silicon negative electrode has been particularly rapid. The silicon negative electrode will expand more. After the design is compact and the expansion is achieved, the probability of the anode at the corner of the outer ring contacting the aluminum layer of the aluminum-plastic film will increase. However, electrochemical corrosion will occur when the two are in contact. After the aluminum layer is corroded, water vapor enters, causing problems such as battery cell swelling and leakage.
[0003] Currently, many silicon-anode batteries have a protective adhesive layer applied to the side to prevent contact between the outer anode and the aluminum-plastic film, thus preventing electrochemical corrosion. However, this method requires a large amount of protective adhesive and can easily lead to poor flatness during bare cell assembly. This can cause portions of the bare cell to remain in contact with the aluminum-plastic film for extended periods, easily damaging the film and resulting in poor safety and stability. Utility Model Content
[0004] The purpose of the utility model is to provide an aluminum-plastic film structure to solve the technical problems of poor safety and stability in existing technology.
[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0006] An aluminum-plastic film structure includes a film body and an adhesive partition component; the inner surface of the film body is provided with a groove; a wall is provided in the groove; the adhesive partition component is arranged in the groove; the adhesive partition component abuts against the wall; and one end of the adhesive partition component extends toward the opening of the groove.
[0007] Preferably, the adhesive separation component includes a stacked adhesive layer and a liquid absorption layer; the wall surface includes a bottom wall surface; the adhesive layer is connected to the bottom wall surface; one end of the liquid absorption layer extends toward the opening of the groove; the liquid absorption layer is used to abut against the corner section of the electrode in the battery cell.
[0008] Preferably, the material of the adhesive layer is an acrylic adhesive layer or a styrene-isoprene-styrene layer; and / or the material of the liquid absorbing layer is ceramic or polyvinylidene fluoride.
[0009] Preferably, the surface area S1 of the bonding separation member satisfies: 1 mm 2 ≤S1≤300mm 2 ;
[0010] And / or, the sum of the thickness h1 of the liquid absorbing layer and the thickness h2 of the adhesive layer satisfies: 2um≤h1+h2≤500um.
[0011] Preferably, the wall surface further includes a first side wall, a second side wall, a third side wall and a fourth side wall arranged in sequence; and a first angle wall surface is provided between the first side wall and the second side wall; a second angle wall surface is provided between the second side wall and the third side wall; a third angle wall surface is provided between the third side wall and the fourth side wall; and a fourth angle wall surface is provided between the first side wall and the fourth side wall.
[0012] And the number of the adhesive partition components is at least two; the side end of each of the adhesive partition components abuts against the first angle wall surface, the second angle wall surface, the third angle wall surface, or the fourth angle wall surface.
[0013] Preferably, the projection of the bonding and separating component toward the first angled wall surface covers the first angled wall surface;
[0014] And / or, the projection of the bonding and separating member toward the second angled wall surface covers the second angled wall surface;
[0015] And / or, the projection of the bonding and separating component toward the third angle wall surface covers the third angle wall surface;
[0016] And / or, a projection of the adhesive partition component toward the fourth angle wall surface covers the fourth angle wall surface.
[0017] Preferably, at least one corner section of a pole piece in the battery cell is connected to the adhesive separation component covered by two angled walls corresponding to the corner section.
[0018] The utility model also discloses a battery cell, comprising a wound battery cell body and the above-mentioned aluminum-plastic film structure; a placement cavity is provided in the film body; a placement cavity is provided in the film body; the wound battery cell body is arranged in the groove provided on the inner surface of the film body; and the structure of the wound battery cell body located in the corner section abuts against the adhesive separation component.
[0019] Preferably, the wound battery cell body includes a first pole piece, an isolation film and a second pole piece stacked in sequence; and the first pole piece, the isolation film and the second pole piece are wound in sequence to form a wound body; the polarity of the first pole piece is opposite to the polarity of the second pole piece.
[0020] The utility model also discloses a battery, comprising the battery core.
[0021] The beneficial effect of the present invention is that the technical solution can effectively ensure the surface flatness of the aluminum-plastic film structure by adding a groove on the surface of the membrane body and adding an adhesive separation component in the wall of the groove, and at the same time use the adhesive separation component for the contact position between the battery cell, thereby reducing the use of surface separation green glue, thereby effectively preventing the battery cell from directly contacting the metal material of the aluminum-plastic film, avoiding the electrode piercing the PP layer of the aluminum-plastic film in the late cycle, resulting in electrochemical corrosion between the anode and the aluminum layer, causing the aluminum layer to be damaged and leaking; thereby improving the stability of the overall structure and ensuring the safety of use. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The following will refer to the attached Figures 1 to 6 To describe the features, advantages and technical effects of exemplary embodiments of the present invention.
[0023] Figure 1 This is a structural diagram of an aluminum-plastic film structure according to an embodiment of the present invention;
[0024] Figure 2 This is a structural diagram of an aluminum-plastic film structure according to an embodiment of the present invention;
[0025] Figure 3 This is a structural schematic diagram of the AA section of the aluminum-plastic film structure according to one embodiment of the present invention;
[0026] Figure 4 This is a schematic structural diagram of a battery cell according to an embodiment of the present invention;
[0027] Figure 5 This is a structural diagram of a wound battery cell body according to an embodiment of the present invention;
[0028] Figure 6 This is a schematic structural diagram of a battery cell according to an embodiment of the present invention.
[0029] In the figure: 1-membrane body; 11-groove; 1101-bottom wall; 111-first side wall; 112-second side wall; 113-third side wall; 114-fourth side wall; 115-first angle wall; 116-second angle wall; 117-third angle wall; 118-fourth angle wall; 119-placement cavity; 2-bonding partition component; 21-adhesive layer; 22-liquid absorption layer; 4-wall; 100-wound battery cell body; 101-first pole piece; 102-second pole piece; 103-isolating membrane; 201-ending section; 202-straight section; 203-starting section; 204-corner section. DETAILED DESCRIPTION
[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned figure descriptions are intended to cover non-exclusive inclusions.
[0031] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.
[0032] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0033] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or multiple situations exist. In addition, the character " / " in this document generally indicates that the related objects are in an "or" relationship.
[0034] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.
[0035] The following is combined with Figures 1 to 6 The present invention is further described in detail, but is not intended to limit the present invention.
[0036] like Figure 1 and 2As shown, in one embodiment of the present utility model, the aluminum-plastic film structure includes a film body 1 and an adhesive separator 2; the inner surface of the film body 1 is provided with a groove 11; a wall 4 is provided in the groove 11; the adhesive separator 2 is arranged in the groove 11; the adhesive separator 2 abuts against the wall 4; and one end of the adhesive separator 2 extends toward the opening of the groove 11; the adhesive separator 2 is used to abut against the corner section 204 of the electrode in the battery cell.
[0037] The technical solution of the present invention is to add a groove on the surface of the membrane body and add an adhesive separation component in the wall of the groove. At the same time, the adhesive separation component is used for the contact position between the battery cell, which can effectively ensure the surface flatness of the aluminum-plastic film structure and reduce the use of surface separation green glue, thereby effectively preventing the battery cell from directly contacting the metal material (aluminum) of the aluminum-plastic film, avoiding the electrode piercing the PP layer of the aluminum-plastic film in the late cycle, resulting in electrochemical corrosion between the anode and the aluminum layer, causing the aluminum layer to be damaged and leaking; thereby improving the stability of the overall structure and ensuring the safety of use.
[0038] Specifically, in some embodiments, Figure 1 and 2 As shown, the wall surface 4 includes a first side wall 111, a second side wall 112, a third side wall 113 and a fourth side wall 114 arranged in sequence; and a first angle wall surface 115 is provided between the first side wall 111 and the second side wall 112; a second angle wall surface 116 is provided between the second side wall 112 and the third side wall 113; a third angle wall surface 117 is provided between the third side wall 113 and the fourth side wall 114; a fourth angle wall surface 118 is provided between the first side wall 111 and the fourth side wall 114; and the number of the adhesive partition components 2 is at least two; the side end of each of the adhesive partition components 2 abuts against the first angle wall surface 115 or the second angle wall surface 116 or the third angle wall surface 117 or the fourth angle wall surface 118. Wherein, as Figure 2 As shown, there are four adhesive separators 2, and the side end of each adhesive separator 2 abuts the first angle wall 115, the second angle wall 116, the third angle wall 117, or the fourth angle wall 118 at the corresponding position. In other words, the adhesive separators 2 isolate and protect the four corners within the groove 11, effectively preventing the battery cell from directly contacting the metal material (aluminum) of the aluminum-plastic film. This prevents the electrode from piercing the PP layer of the aluminum-plastic film during late cycling, which could lead to electrochemical corrosion between the anode and the aluminum layer, resulting in damage to the aluminum layer and leakage. This improves the stability of the overall structure and ensures safety in use.
[0039] Specifically, in some embodiments, Figure 2 and 3 As shown, the projection of the adhesive partition component 2 toward the first angled wall surface 115 covers the first angled wall surface 115; and / or, the projection of the adhesive partition component 2 toward the second angled wall surface 116 covers the second angled wall surface 116; and / or, the projection of the adhesive partition component 2 toward the third angled wall surface 117 covers the third angled wall surface 117; and / or, the projection of the adhesive partition component 2 toward the fourth angled wall surface 118 covers the fourth angled wall surface 118. Figure 3 As shown, each adhesive separation component 2 fully abuts and covers the corresponding first angle wall 115 or the second angle wall 116 or the third angle wall 117 or the fourth angle wall 118; so as to achieve separation protection of the four corners over a larger area, thereby effectively preventing the battery cell from directly contacting the metal material (aluminum) of the aluminum-plastic film, avoiding the electrode piercing the PP layer of the aluminum-plastic film in the later stage of the cycle, causing the anode to contact the aluminum layer to produce electrochemical corrosion, resulting in damage to the aluminum layer and leakage; thereby improving the stability of the overall structure and ensuring safety in use.
[0040] Specifically, in some embodiments, at least one corner segment 204 of a cell electrode sheet is connected to the adhesive separator 2 covered by two angled walls corresponding to the corner segment 204 (two adjacent angled walls among the first angled wall 115, the second angled wall 116, the third angled wall 117, and the fourth angled wall 118). This structure can achieve separation and protection of the outermost anode sheet at the cell corner through the adhesive separator 2 on the two angled walls, further improving practical safety and stability.
[0041] Specifically, in some embodiments, Figure 2 and 3 As shown, the adhesive separator 2 includes a laminated adhesive layer 21 and a liquid-absorbing layer 22; the wall surface 4 also includes a bottom wall surface 1101; the adhesive layer 21 is connected to the bottom wall surface 1101; one end of the liquid-absorbing layer 22 extends toward the opening of the groove 11; and the liquid-absorbing layer 22 abuts against the corner section 204 of the electrode in the battery cell. This structure ensures the stability of the adhesive separation component 2 through the adhesive layer 21, and the liquid-absorbing layer 22 absorbs part of the electrolyte to form a buffer structure, thereby achieving a certain degree of flexibility of the adhesive separation component 2, providing a certain buffering effect in the drop test. This can improve the safety and stability of use, and can effectively prevent the battery cell from directly contacting the metal material (aluminum) of the aluminum-plastic film, preventing the electrode from piercing the PP layer of the aluminum-plastic film in the later stages of the cycle, resulting in electrochemical corrosion between the anode and the aluminum layer, causing damage to the aluminum layer and leakage.
[0042] Specifically, in some embodiments, the adhesive layer 21 is made of an acrylic adhesive layer or a styrene-isoprene-styrene layer, while the liquid-absorbing layer 22 is made of ceramic or PVDF (polyvinylidene fluoride). This structure further ensures the stability of the adhesive bond to the separator 2 by using the acrylic adhesive layer or the styrene-isoprene-styrene layer. Furthermore, the ceramic or PVDF layer can better absorb a portion of the electrolyte to form a buffer structure, thereby enhancing the flexibility of the separator 2.
[0043] Specifically, in some embodiments, Figure 3 As shown, the relationship between the thickness h1 of the liquid-absorbing layer 22, the thickness h2 of the adhesive layer 21, and the thickness h3 of the groove 11 satisfies: h3 ≤ h1 + h2. In other words, one end of the adhesive separator 2 can extend to the opening of the groove 11 or extend through the opening of the groove 11 to improve the contact convenience between the electrode and the battery cell, thereby effectively preventing the battery cell from directly contacting the metal material (aluminum) of the aluminum-plastic film, preventing the electrode from piercing the PP layer of the aluminum-plastic film in the later stages of the cycle, resulting in electrochemical corrosion between the anode and the aluminum layer, causing damage to the aluminum layer and leakage; thereby improving the stability of the overall structure and ensuring safety in use.
[0044] Specifically, in some embodiments, the surface area S1 of each of the adhesive separation components 2 satisfies: 1 mm 2 ≤S1≤300mm 2 The sum of the thickness h1 of the liquid absorbing layer 22 and the thickness h2 of the adhesive layer 21 satisfies the following: 2um≤h1+h2≤500um. In other words, a bonding separator 2 of a reasonable size can improve the protection performance, prevent the electrode in the corner from contacting the metal material in the corner, and thus prevent the electrode from piercing the PP layer of the aluminum-plastic film in the later stages of the cycle, causing electrochemical corrosion between the anode and the aluminum layer, resulting in damage to the aluminum layer and leakage; thereby improving the stability of the overall structure and ensuring safety in use.
[0045] Specifically, in some embodiments, Figure 3 As shown, the relationship between the thickness h3 of the groove 11 and the thickness h4 of the membrane body 1 satisfies: 20%*h4≤h3≤50%*h4. This structure can ensure the assembly stability of the adhesive separation component 2 and ensure the orderly realization of its separation function through the groove 11 of reasonable size.
[0046] The present invention also provides a battery cell, which includes a wound battery cell body 100 and an aluminum-plastic film structure. The specific structure of the aluminum-plastic film structure refers to the above embodiments. Since the present battery cell adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described in detail here. Figure 4 and 5 As shown in FIG6 , the membrane body 1 is provided with a placement cavity 119; the wound cell body 100 is provided inside the placement cavity 119; and the wound cell body 100 is provided in the groove 11 provided on the inner surface of the membrane body 1; the wound cell body 100 is provided with a tail section 201, a starting section 203, at least two corner sections 204 and at least two straight sections 202; one end of the starting section 203 is connected to one end of one of the corner sections 204; the other end of one of the corner sections 204 is connected to one of the straight sections 20 2; the other end of one straight segment 202 is connected to one end of the other corner segment 204; the other end of the other corner segment 204 is connected to one end of the other straight segment 202; the other end of the other straight segment 202 is connected to one end of the finishing segment 201; and the projection of the structure of the wound cell body 100 located in the corner segment 204 toward the groove 11 is disposed within the groove 11; and the structure of the wound cell body 100 located in the corner segment 204 abuts against the adhesive separator 2 (middle liquid-absorbing layer 22). Furthermore, the starting segment 203 is the beginning portion of the winding process of the wound cell body 100.
[0047] Among them, such as Figure 4 As shown, the wound cell body 100 includes a first pole piece 101, a separator 103, and a second pole piece 102 stacked in sequence; and the first pole piece 101, the separator 103, and the second pole piece 102 are wound in sequence to form a wound body; the polarity of the first pole piece 101 is opposite to the polarity of the second pole piece 102. Figure 4 As shown, the first electrode 101 is an anode electrode; the second electrode 102 is a cathode electrode.
[0048] The negative electrode current collector can be made of copper, and the negative electrode active material layer includes a negative electrode active material such as carbon or silicon. The positive electrode current collector can be made of aluminum, and the positive electrode active material layer includes a positive electrode active material such as lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The separator 103 can be made of PP (polypropylene) or PE (polyethylene).
[0049] The present invention also provides a battery, which includes a battery cell. The specific structure of the battery cell refers to the above embodiments. Since the battery adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.
[0050] A battery refers to a cup, tank, or other container, or a portion of a composite container, that contains an electrolyte solution and metal electrodes to generate an electric current. It is a device capable of converting chemical energy into electrical energy. Batteries have positive and negative electrodes. With technological advancements, batteries have become a general term for small devices that can generate electrical energy, such as solar cells. Key battery performance parameters include electromotive force, capacity, specific energy, and resistance. Battery Principle: In chemical batteries, the direct conversion of chemical energy into electrical energy occurs through spontaneous chemical reactions within the battery, such as oxidation and reduction, which occur at the two electrodes. The negative electrode active material consists of a reducing agent with a relatively negative potential and is stable in the electrolyte, such as active metals like zinc, cadmium, and lead, and hydrogen or hydrocarbons. The positive electrode active material consists of an oxidizing agent with a relatively positive potential and is stable in the electrolyte, such as metal oxides like manganese dioxide, lead dioxide, and nickel oxide, oxygen or air, halogens and their salts, and oxygen-containing acids and their salts. The electrolyte is a material with good ionic conductivity, such as aqueous solutions of acids, bases, and salts, organic or inorganic non-aqueous solutions, molten salts, or solid electrolytes.
[0051] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.
[0052] Based on the disclosure and teachings of the above description, those skilled in the art will be able to make changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments described above. Any obvious improvements, substitutions, or modifications made by those skilled in the art based on the present invention fall within the scope of protection of the present invention. In addition, although certain specific terms are used in this description, these terms are for convenience only and do not constitute any limitation on the present invention.
Claims
1. An aluminum-plastic film structure, characterized in that: It includes a membrane body and an adhesive partition component; the inner surface of the membrane body is provided with a groove; a wall is provided in the groove; the adhesive partition component is arranged in the groove; the adhesive partition component abuts against the wall; and one end of the adhesive partition component extends toward the opening of the groove.
2. The aluminum-plastic film structure according to claim 1, characterized in that: The adhesive separation component includes a stacked adhesive layer and a liquid absorption layer; the wall surface includes a bottom wall surface; the adhesive layer is connected to the bottom wall surface; one end of the liquid absorption layer extends toward the opening of the groove; the liquid absorption layer is used to abut against the corner section of the electrode in the battery cell.
3. The aluminum-plastic film structure according to claim 2, characterized in that: The material of the bonding layer is an acrylic adhesive layer or a styrene-isoprene-styrene layer; and / or the material of the liquid absorbing layer is ceramic or polyvinylidene fluoride.
4. The aluminum-plastic film structure according to claim 2, characterized in that: The surface area S1 of the adhesive separation component satisfies: 1mm 2 ≤S1≤300mm 2 ; And / or, the sum of the thickness h1 of the liquid absorbing layer and the thickness h2 of the adhesive layer satisfies: 2um≤h1+h2≤500um.
5. The aluminum-plastic film structure according to claim 1 or 2, characterized in that: The wall surface further includes a first side wall, a second side wall, a third side wall and a fourth side wall arranged in sequence; a first angle wall surface is provided between the first side wall and the second side wall; a second angle wall surface is provided between the second side wall and the third side wall; a third angle wall surface is provided between the third side wall and the fourth side wall; and a fourth angle wall surface is provided between the first side wall and the fourth side wall; And the number of the adhesive partition components is at least two; the side end of each of the adhesive partition components abuts against the first angle wall surface, the second angle wall surface, the third angle wall surface, or the fourth angle wall surface.
6. The aluminum-plastic film structure according to claim 5, characterized in that: The projection of the adhesive separation component toward the first angle wall surface covers the first angle wall surface; And / or, the projection of the bonding and separating member toward the second angled wall surface covers the second angled wall surface; And / or, the projection of the bonding and separating component toward the third angle wall surface covers the third angle wall surface; And / or, a projection of the adhesive partition component toward the fourth angle wall surface covers the fourth angle wall surface.
7. The aluminum-plastic film structure according to claim 6, characterized in that: At least one corner section of the electrode in the battery core is connected to the adhesive separation component covered by the two angled walls corresponding to the corner section.
8. A battery cell, characterized in that: It comprises a wound battery cell body and the aluminum-plastic film structure described in any one of claims 1 to 7; an inner cavity is provided in the film body; the wound battery cell body is arranged in the groove provided on the inner surface of the film body; and the structure of the wound battery cell body located in the corner section abuts against the adhesive separation component.
9. The battery cell according to claim 8, characterized in that: The wound battery cell body includes a first pole piece, an isolation film, and a second pole piece stacked in sequence; and the first pole piece, the isolation film, and the second pole piece are wound in sequence to form a wound body; the polarity of the first pole piece is opposite to that of the second pole piece.
10. A battery, characterized in that: Comprising the battery cell according to claim 8 or 9.