Integrated flexible paper electrode containing paper-based current collector, preparation method of integrated flexible paper electrode and battery

Abstract

The invention provides an integrated flexible paper electrode containing a paper-based current collector, a preparation method of the integrated flexible paper electrode and a battery, the paper electrode comprises the paper-based current collector, and the paper-based current collector is located in the paper-based electrode and is covered by the paper-based electrode. A part of one end of the paper-based current collector extends out of the paper-based electrode to serve as a tab connected with an external circuit. The preparation method comprises the following steps: firstly, carrying out suction filtration on a mixed solution of cellulose and a carbon-based material to a filter membrane, covering a part of area by using the filter membrane, then carrying out suction filtration treatment on the mixed solution containing the cellulose, the carbon-based material and an electrode active material, and carrying out vacuum drying treatment to obtain the integrated structure flexible paper electrode containing the paper-based current collector. And finally, the integrated flexible paper battery containing the paper-based current collector is obtained by combining a flexible battery packaging technology, so that the problem that a flexible paper electrode cannot be externally connected with a tab is solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of secondary batteries, and particularly relates to an integrated flexible paper electrode containing a paper-based current collector and a preparation method and a battery thereof. BACKGROUND

[0002] With the rapid development of science and technology, the field of flexible electronics and smart wearable devices is showing an explosive growth trend, and the market demand for lightweight, bendable and excellent performance flexible batteries is increasingly urgent. Traditional rigid batteries have significant defects such as large volume, heavy weight and inability to adapt to dynamic deformation, making it difficult to achieve good integration with flexible devices and unable to meet the special requirements of flexible electronic devices for power modules.

[0003] In recent years, flexible battery technology has made some progress, and through the introduction of ultra-thin metal current collectors (such as copper foil, aluminum foil) or conductive polymers, the flexibility of the battery has been improved to some extent. However, this technical path still faces many problems. On the one hand, the high material cost makes it difficult to reduce the production cost of flexible batteries, limiting their large-scale commercial application; on the other hand, the preparation process is complex, involving multiple high-precision and high-cost processes, increasing the production difficulty and cost. More importantly, the cycle life of flexible batteries is insufficient, and after several charge and discharge cycles, the battery performance will decrease significantly, seriously affecting its service life and reliability. Especially in extreme bending or stretching application scenarios, the metal current collector used in traditional flexible battery technology has fatal defects. The metal current collector is prone to breakage when subjected to a large stress, and its bonding force with the active material is weak, so the active material is easy to fall off from the current collector during bending or stretching, causing damage to the internal structure of the battery and thus causing the battery to fail. This series of problems greatly limits the application range of flexible batteries in complex and variable environments, hindering the further development of flexible battery technology. SUMMARY

[0004] The present application provides an integrated flexible paper electrode containing a paper-based current collector and a preparation method and a battery thereof to overcome the deficiencies of the prior art.

[0005] The present application is achieved by the following technical solutions:

[0006] An integrated flexible paper electrode containing a paper-based current collector, comprising a paper-based current collector, the paper-based current collector being located in a paper-based electrode and covered by the paper-based electrode, and one end of the paper-based current collector extending out of the paper-based electrode as a tab for connecting to an external circuit.

[0007] The present application also provides a preparation method of an integrated flexible paper electrode containing a paper-based current collector, comprising the following steps:

[0008] Step 1: performing suction filtration treatment on a mixed solution containing cellulose and carbon-based material to obtain a paper-based current collector;

[0009] Step 2: covering the edge area of one side of the paper-based current collector with a filter membrane;

[0010] Step 3: performing suction filtration on a mixed solution containing cellulose, carbon-based material and electrode active material onto the paper-based current collector with the edge area covered to obtain a paper-based electrode with a laminated structure;

[0011] Step 4: performing vacuum drying treatment on the obtained paper-based material with a laminated structure, and then cutting off the paper electrode part of the filter membrane covered area to expose the paper-based current collector to obtain an integrated flexible paper electrode containing the paper-based current collector.

[0012] Further, the cellulose material in Step 1 and Step 3 is any one of coniferous wood fiber, broadleaf wood fiber, cotton fiber and bamboo fiber.

[0013] Further, the carbon-based material in Step 1 and Step 3 is any one of single-walled carbon nanotube, multi-walled carbon nanotube, carboxylated carbon nanotube and multi-layer graphene.

[0014] Further, in Step 1, the mass ratio of cellulose and carbon-based material is 1-2:1.

[0015] Further, in Step 3, the mass ratio of cellulose, carbon-based material and electrode active material is 0.5-3:1:1-5.

[0016] Further, the filter membrane is a water-based filter membrane.

[0017] Further, in Step 3, the electrode active material is positive electrode active material or negative electrode active material, wherein the positive electrode active material is any one of lithium iron phosphate, lithium cobaltate, nickel cobalt manganese oxide, sodium cobalt oxide, sodium manganese oxide, sodium iron phosphate, organic sulfide, potassium cobalt oxide, potassium molybdenum oxide, potassium iron phosphate, manganese dioxide and activated carbon; and the negative electrode material is any one of graphite, silicon-based material, silicon-carbon composite material, hard carbon, soft carbon, conductive polymer, zinc powder and activated carbon.

[0018] The application also provides a flexible battery using the above-mentioned integrated flexible paper electrode containing a paper-based current collector as the positive electrode or / and negative electrode of the battery.

[0019] Compared with the prior art, the application has the beneficial effects that:

[0020] The application uses a simple filtration process to construct an integrated flexible paper electrode containing a paper-based current collector, solving the problem of external tabs for flexible paper electrodes. This method can be compatible with the characteristics of paper-based electrodes, and through material design and process coordination, it can achieve high conductivity, strong toughness and fatigue-resistant electrode connection, thereby promoting the development and application of flexible paper batteries. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 A structural diagram of an integrated flexible paper electrode containing a paper-based current collector.

[0022] In the figure, the reference numerals are: 1-paper-based electrode, 2-paper-based current collector, 3-external circuit area. DETAILED DESCRIPTION

[0023] Exemplary embodiments of the present application will be described in greater detail below with reference to the accompanying drawings. Although exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present application can be more thoroughly understood and the scope of the present application can be accurately conveyed to those skilled in the art. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0024] In order for those skilled in the art to better understand the technical solutions of the present application, the present application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] The embodiments of the present application provide a preparation method of an integrated flexible paper electrode containing a paper-based current collector, which comprises the following steps:

[0026] Step 1: performing filtration treatment on a mixed solution containing cellulose and carbon-based materials;

[0027] Step 2: using a filter membrane to cover part of the paper-based current collector obtained in step 1;

[0028] Step 3: performing filtration on a mixed solution containing cellulose, carbon-based materials and electrode active materials onto the paper-based current collector with the edge part area covered in step 2;

[0029] Step 4: performing vacuum drying treatment on the paper-based material with a laminated structure obtained in step 3, and then cutting off the paper electrode part of the filter membrane covered area to obtain an integrated flexible paper electrode containing a paper-based current collector.

[0030] The structure of the integrated flexible paper electrode containing a paper-based current collector prepared by the above method is as shown in Figure 1As shown, the paper-based current collector 2 is located in the paper-based electrode 1 and is covered by the paper-based electrode 1, and an outer circuit region 3 at one end of the paper-based current collector 2 extending out of the paper-based electrode 1 serves as a tab for connecting with an external circuit.

[0031] The application will be further described in conjunction with specific examples.

[0032] Example 1:

[0033] Step 1: A mixed solution containing coniferous wood fibers and multi-walled carbon nanotubes is subjected to vacuum suction filtration on a water-based filter membrane, wherein the mass ratio of the coniferous wood fibers and the multi-walled carbon nanotubes is 1:1;

[0034] Step 2: The edge portion region of the paper-based current collector obtained in Step 1 is covered using a water-based filter membrane;

[0035] Step 3: A mixed solution containing coniferous wood fibers, multi-walled carbon nanotubes and lithium iron phosphate active material is suction filtered onto the paper-based current collector obtained in Step 2, wherein the mass ratio of the coniferous wood fibers, the multi-walled carbon nanotubes and the lithium iron phosphate active material is 1:1:1;

[0036] Step 4: The paper-based material with a laminated structure obtained in Step 3 is subjected to vacuum drying treatment, and then the lithium iron phosphate-based paper electrode portion in the filter membrane covered region is cut off to obtain an integrated flexible paper electrode containing a paper-based current collector.

[0037] Example 2:

[0038] Step 1: A mixed solution containing cotton fibers and carboxylated carbon nanotubes is subjected to vacuum suction filtration on a water-based filter membrane, wherein the mass ratio of the cotton fibers and the carboxylated carbon nanotubes is 2:1;

[0039] Step 2: The edge portion region of the paper-based current collector obtained in Step 1 is covered using a water-based filter membrane;

[0040] Step 3: A mixed solution containing cotton fibers, carboxylated carbon nanotubes and graphite active material is suction filtered onto the paper-based current collector obtained in Step 2, wherein the mass ratio of the cotton fibers, the carboxylated carbon nanotubes and the graphite active material is 3:1:5;

[0041] Step 4: The paper-based material with a laminated structure obtained in Step 3 is subjected to vacuum drying treatment, and then the graphite-based paper electrode portion in the filter membrane covered region is cut off to obtain an integrated flexible paper electrode containing a paper-based current collector.

[0042] The application is described in detail above by way of examples, but the content described is only exemplary embodiments of the application and cannot be considered to limit the implementation scope of the application. The protection scope of the application is defined by the claims. Any similar technical solutions that utilize the technical solutions described in the application or are inspired by the technical solutions of the application within the spirit and protection scope of the application, and achieve the above technical effects, or equivalent changes and improvements to the application scope, should still belong to the patent protection scope of the application.

Claims

1. An integrated flexible paper electrode comprising a paper-based current collector, characterized in that: The paper-based current collector comprises a paper-based current collector, which is located in a paper-based electrode and covered by the paper-based electrode. One end of the paper-based current collector partially extends from the paper-based electrode to serve as a tab connected to an external circuit.

2. The method for preparing an integrated flexible paper electrode comprising a paper-based current collector according to claim 1, characterized in that: The following steps are involved: Step 1: filtering a mixed solution containing cellulose and carbon-based materials to obtain a paper-based current collector; Step 2: Use a filter membrane to cover the edge area of ​​one side of the paper-based current collector; Step 3: Filtering a mixed solution containing cellulose, carbon-based material, and electrode active material onto a paper-based current collector covering the edge area to obtain a paper-based electrode having a laminated structure; Step 4: vacuum drying the obtained paper-based material with a laminated structure, and then cutting off the paper electrode portion in the filter membrane covering area to expose the paper-based current collector, thereby obtaining an integrated flexible paper electrode containing a paper-based current collector.

3. The method according to claim 2, characterized in that The cellulose material in step 1 and step 3 is any one of softwood fiber, hardwood fiber, cotton fiber and bamboo fiber.

4. The method according to claim 2, characterized in that In step 1 and step 3, the carbon-based material is any one of single-walled carbon nanotubes, multi-walled carbon nanotubes, carboxylated carbon nanotubes, and multilayer graphene.

5. The method according to claim 2, characterized in that In step 1, the mass ratio of cellulose to carbon-based material is 1 to 2:

1.

6. The method according to claim 2, characterized in that In step 3, the mass ratio of cellulose, carbon-based material and electrode active material is 0.5-3:1:1-5.

7. The method according to claim 2, characterized in that The filter membrane is a water filter membrane.

8. The method according to claim 2, characterized in that In step 3, the electrode active material is a positive electrode active material or a negative electrode active material.

9. A flexible battery, characterized in that: The integrated flexible paper electrode comprising a paper-based current collector as claimed in claim 1 is used as the positive electrode and / or negative electrode of the battery.

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