Low internal resistance polymer battery with gradient porosity electrodes

Abstract

The utility model discloses a low internal resistance polymer battery of gradient pore electrode relates to battery technical field, including positive pole, negative pole, the polymer electrolyte layer of being located between positive pole and negative pole, at least one pole in positive pole and negative pole adopts the gradient pore structure with the pore size that gradually changes from surface to inside, still include multilayer composite type casing structure, multilayer composite type casing structure includes protective outer layer, intermediate functional layer and internal sealing layer, the utility model discloses by adopting the gradient pore structure with the pore size that gradually changes from surface to inside, optimized ion transmission path, reduced ion diffusion resistance to the overall internal resistance of battery is reduced significantly. This design makes the battery more efficient in the process of charge and discharge, improves energy conversion efficiency, in addition, the self -repairing mechanism that contains in the intermediate functional layer can heal microcracks automatically when electrode is slightly damaged, prolongs the service life and cycle stability of battery.

Description

Technical Field

[0001] This invention relates to the field of battery technology, specifically to a low internal resistance polymer battery with gradient pore electrodes. Background Technology

[0002] With the development of portable electronic devices and electric vehicles, the demand for high-performance batteries is increasing. However, traditional polymer batteries often face problems such as high internal resistance and limited energy density. Therefore, developing novel electrode structures to reduce battery internal resistance has become a research hotspot. Gradient pore electrodes are electrode materials with specific structural characteristics, characterized by a gradual change in pore size from one end of the electrode to the other (i.e., a gradient). This design can optimize ion transport pathways, improve electrolyte permeability, and enhance the contact between the electrode material and the electrolyte. These factors all contribute to reducing battery internal resistance, thereby improving the overall performance of the battery.

[0003] Polymer batteries are a type of battery that uses polymers as electrolytes. They are known for their lightweight, thinness, and high energy density. However, traditional polymer batteries may suffer from high internal resistance, which limits their performance in high-power applications. By employing gradient pore electrode technology, the internal resistance of polymer batteries can be effectively reduced, improving their charge / discharge rate and cycle life. Therefore, this invention proposes a low-internal-resistance polymer battery with a gradient pore electrode. Utility Model Content

[0004] Technical problems to be solved

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a low internal resistance polymer battery with gradient pore electrodes.

[0006] Technical solution

[0007] To achieve the above objectives, this utility model provides the following technical solution: a low internal resistance polymer battery with a gradient pore electrode, characterized in that: it includes a positive electrode, a negative electrode, and a polymer electrolyte layer located between the positive and negative electrodes; at least one of the positive and negative electrodes adopts a gradient pore structure with pore size gradually changing from the surface to the interior;

[0008] It also includes a multi-layer composite shell structure, which includes a protective outer layer, an intermediate functional layer and an internal sealing layer. The protective outer layer includes carbon fiber reinforced polyimide with a thickness of 0.1–0.5 mm, and the surface of the carbon fiber reinforced polyimide is coated with nano-alumina. The intermediate functional layer is a graphene-reinforced phase change-self-healing composite functional layer, and the internal sealing layer is an Al2O3 / PET composite film with a thickness of 50–100 μm.

[0009] Preferably, the phase change material of the graphene-enhanced phase change-self-healing composite functional layer is a paraffin / graphene composite, and its self-healing material is a thermally responsive polymer based on the Diels-Alder reaction.

[0010] Preferably, the method further includes a current collector, which includes an aluminum current collector located on the positive electrode side and a copper current collector located on the negative electrode side. The positive and negative electrodes have smaller pore sizes on the side closer to the current collector and larger pore sizes on the side closer to the polymer electrolyte layer.

[0011] Preferably, the porosity of the gradient pore structure is 30%-70%.

[0012] Preferably, the positive or negative electrode material is a nanocomposite material.

[0013] Preferably, the nanocomposite material of the positive electrode includes one of lithium transition metal oxide, lithium-rich manganese-based oxide, or sulfide.

[0014] Preferably, the nanocomposite material of the negative electrode includes one of graphite, silicon-based materials, lithium titanate, metal oxides, and sulfides or alloys.

[0015] Preferably, the polymer electrolyte comprises a matrix polymer, a lithium salt, a plasticizer, and nanofillers.

[0016] Preferably, the polymer electrolyte also contains an antioxidant and a viscosity modifier.

[0017] Beneficial effects:

[0018] Compared with existing technologies, the low internal resistance polymer battery with this gradient pore electrode has the following advantages:

[0019] I. This invention optimizes the ion transport path and reduces ion diffusion resistance by employing a gradient pore structure with gradually changing pore size from the surface to the interior, thereby significantly reducing the overall internal resistance of the battery. This design makes the battery more efficient during charging and discharging, improving energy conversion efficiency. The gradient pore structure effectively alleviates the volume expansion problem of electrode materials during charging and discharging, especially for high-capacity negative electrode materials. In addition, the self-healing mechanism contained in the intermediate functional layer can automatically heal microcracks when the electrode is slightly damaged, extending the battery's lifespan and cycle stability.

[0020] II. The protective outer layer of this utility model includes carbon fiber reinforced polyimide combined with nano-alumina coating, which gives the battery excellent impact resistance, puncture resistance and weather resistance. The Al2O3 / PET composite film ensures airtightness and waterproof performance, prevents moisture and oxygen from entering the battery, avoids electrolyte degradation, and ensures long-term reliability. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of this utility model;

[0023] Figure 2 This is a schematic diagram of the planar cross-sectional structure of this utility model;

[0024] Figure 3 This is a cross-sectional structural diagram of the present invention;

[0025] Figure 4 This is a schematic diagram of the multi-layer composite shell structure of this utility model.

[0026] In the picture:

[0027] 1. Positive electrode; 2. Negative electrode; 3. Polymer electrolyte layer; 4. Current collector; 5. Gradient pore structure; 6. Multi-layer composite shell structure; 401. Aluminum current collector; 402. Copper current collector; 601. Protective outer layer; 602. Intermediate functional layer; 603. Internal sealing layer; 6011. Carbon fiber reinforced polyimide; 6012. Nano-alumina layer. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Please see Figures 1-4As shown, this utility model provides a technical solution: a low internal resistance polymer battery with a gradient pore electrode, comprising a positive electrode 1, a negative electrode 2, and a polymer electrolyte layer 3 located between the positive and negative electrodes. The polymer electrolyte 3 comprises a matrix polymer, a lithium salt, a plasticizer, and nanofillers. The polymer electrolyte 3 also contains an antioxidant and a viscosity modifier. The positive electrode 1 or the negative electrode 2 is made of a nanocomposite material. The nanocomposite material of the positive electrode 1 includes one of lithium transition metal oxides, lithium-rich manganese-based oxides, or sulfides. The nanocomposite material of the negative electrode 2 includes one of graphite, silicon-based materials, lithium titanate, metal oxides, sulfides, or alloy materials. At least one of the positive electrode 1 and the negative electrode 2 adopts a gradient pore structure 5 with a gradually changing pore size from the surface to the interior. The porosity of the gradient pore structure 5 is 30%-70%.

[0030] This utility model also includes a multi-layer composite shell structure 6, which includes a protective outer layer 601, an intermediate functional layer 602, and an inner sealing layer 603. The protective outer layer 601 includes a carbon fiber reinforced polyimide layer 6011 with a thickness of 0.1–0.5 mm, and the surface of the carbon fiber reinforced polyimide layer 6011 is coated with a nano-alumina layer 6012. The intermediate functional layer 602 is a graphene-reinforced phase change-self-healing composite functional layer, and the inner sealing layer 603 is an Al2O3 / PET composite film with a thickness of 50–100 μm.

[0031] The phase change material of the graphene-enhanced phase change-self-healing composite functional layer in this invention is a paraffin / graphene composite, and its self-healing material is a thermally responsive polymer based on the Diels-Alder reaction.

[0032] Please refer to the following carefully. Figure 1 and Figure 2 The device also includes a current collector 4, which includes an aluminum current collector 401 located on the positive electrode 1 side and a copper current collector 402 located on the negative electrode 2 side. The positive and negative electrodes have smaller pore sizes on the side closer to the current collector 4 and larger pore sizes on the side closer to the polymer electrolyte layer 3.

[0033] Working principle: By employing a gradient pore structure with pore sizes gradually changing from the surface to the interior, the ion transport path is optimized, reducing ion diffusion resistance and thus significantly lowering the overall internal resistance of the battery. This design makes the battery more efficient during charging and discharging, improving energy conversion efficiency. The gradient pore structure effectively alleviates the volume expansion problem of electrode materials during charging and discharging, especially for high-capacity negative electrode materials. In addition, the self-healing mechanism contained in the intermediate functional layer can automatically heal microcracks when the electrode is slightly damaged, extending the battery's lifespan and cycle stability.

[0034] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A low-internal-resistance polymer battery with gradient pore electrodes, characterized in that: It includes a positive electrode (1), a negative electrode (2), and a polymer electrolyte layer (3) located between the positive and negative electrodes; at least one of the positive electrode (1) and the negative electrode (2) adopts a gradient pore structure (5) with pore size gradually changing from the surface to the interior. It also includes a multi-layer composite shell structure (6), which includes a protective outer layer (601), an intermediate functional layer (602) and an internal sealing layer (603).

2. The low internal resistance polymer battery with gradient pore electrode according to claim 1, characterized in that: It also includes a current collector (4), which includes an aluminum current collector (401) located on the positive electrode (1) side and a copper current collector (402) located on the negative electrode (2) side. The positive and negative electrodes have smaller pore sizes on the side closer to the current collector (4) and larger pore sizes on the side closer to the polymer electrolyte layer (3).

3. The low internal resistance polymer battery with gradient pore electrode according to claim 1, characterized in that: The porosity of the gradient pore structure (5) is 30%-70%.

4. The low internal resistance polymer battery with gradient pore electrode according to claim 1, characterized in that: The positive electrode (1) or negative electrode (2) material is selected from nanocomposite materials.

5. The low internal resistance polymer battery with gradient pore electrode according to claim 1, characterized in that: The nanocomposite material of the positive electrode (1) includes one of lithium transition metal oxide, lithium-rich manganese-based oxide or sulfide.

6. The low internal resistance polymer battery with gradient pore electrode according to claim 1, characterized in that: The nanocomposite material of the negative electrode (2) includes one of graphite, silicon-based materials, lithium titanate, metal oxides and sulfides or alloys.

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