Two-dimensional conductive polymer modified aqueous battery current collector, preparation method and application thereof
Patent Information
- Application Number
- CN202510376105.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-27
- Publication Date
- 2026-09-29
AI Technical Summary
但是目前报道的聚合物修饰层存在着修饰层与集流体结合能力弱、易脱落、涂层导电性差、聚合物修饰层过厚等问题，因而严重影响其在水系离子电池中的发展
[0034]本发明通过引入含有巯基基团的单体用来制备水系电池集流体的二维导电高分子修饰层。首先，借助巯基与金属集流体间形成稳定的化学键，使聚合物修饰层和金属集流体的之间的结合力明显提高，从而消除了常规导电聚合物层存在的易脱落、结合力弱的问题；其次，本发明通过将双连续相微乳液在高离心力和剪切力作用下完成聚合的方式，使导电聚合物二维化，增加其比表面积并使活性位点充分暴露，提高其电导率，促进电池充放电过程中的离子传输；最后，本发明通过改变巯基基团的单体种类，获得了不同钝化程度的集流体，增加水电解能垒，拓宽电化学窗口，能够阻止金属的快速腐蚀。因此，利用本发明提供的制备方法可以使得到的二维导电高分子改性的水系电池集流体兼具了强结合力、高柔性、耐腐蚀、高导电性、强粘结力、耐酸碱的优势，拓宽了可应用于水系离子电池中集流体的可选择范围。
Smart Images
Figure CN122843385A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery materials technology. More specifically, it relates to a two-dimensional conductive polymer-modified aqueous battery current collector, its preparation method, and its application. Background Technology
[0002] Aqueous lithium-ion batteries have broad application prospects in large-scale energy storage due to their high safety and low cost. However, aqueous batteries suffer from serious side reactions, and current research mostly focuses on electrolyte and material modification, with little attention paid to the current collectors. During battery cycling, water electrolysis (hydrogen or oxygen evolution) mainly occurs on the surface of the current collector during charge / discharge cycles. The high activity of water molecules and the influence of pH make it difficult for aluminum and copper current collectors, which are stable in organic lithium-ion batteries, to form a passivation film and suffer from acid and alkali corrosion in aqueous electrolytes. Generally, using acid and alkali resistant titanium and graphite current collectors can solve these problems to some extent, but they still face challenges such as difficulty in cutting, high cost, low flexibility, and limited passivation. Another approach is to passivate the surface of conventional current collectors (such as aluminum, copper, and stainless steel current collectors) to form a polymer modification layer, which is used to prevent rapid corrosion of the metal. However, the polymer-modified layers reported so far have problems such as weak bonding between the modified layer and the current collector, easy detachment, poor conductivity of the coating, and excessive thickness of the polymer-modified layer, which seriously affect their development in aqueous ion batteries. Summary of the Invention
[0003] To address the aforementioned problems, the first objective of this invention is to provide a method for preparing a two-dimensional conductive polymer-modified aqueous battery current collector. Introducing monomers containing thiol groups enhances the bonding force between the modified layer and the metal current collector, thereby improving the conductivity and stability of the aqueous battery current collector in aqueous systems. This preparation method offers advantages such as economy, ease of operation, and outstanding performance, providing a new approach for the development of aqueous battery current collectors.
[0004] The second objective of this invention is to provide a two-dimensional conductive polymer-modified aqueous battery current collector. Because two-dimensional conductive polymers have a large specific surface area and abundant, fully exposed active sites, the resulting two-dimensional conductive polymer-modified aqueous battery current collector exhibits higher flexibility and stronger corrosion resistance, weakens the catalytic decomposition reaction of water, and improves the conductivity and adhesion to the modified layer.
[0005] A third objective of this invention is to provide an application of the aqueous battery current collector modified with the two-dimensional conductive polymer described above in the preparation of aqueous ion batteries.
[0006] To achieve the first objective mentioned above, the present invention adopts the following technical solution:
[0007] This invention discloses a method for preparing a two-dimensional conductive polymer-modified current collector, comprising the following steps:
[0008] S1. Dissolve the monomer containing thiol groups in cyclohexane to form solution A, dissolve the dopant and oxidant in water to form solution B, mix the nonionic surfactant TX-100 and the co-surfactant n-butanol to form solution C, and mix the above three solutions to obtain a bicontinuous microemulsion.
[0009] S2. Pour the bicontinuous microemulsion into a high-speed rotating container, so that the bicontinuous microemulsion in the container forms a uniform liquid film with a thickness of 500-1000 μm on the side wall of the container and polymerizes it to obtain two-dimensional conductive polymer nanosheets.
[0010] S3. Two-dimensional conductive polymer nanosheets are modified onto the surface of the current collector using a blade coating method, and after drying, a two-dimensional conductive polymer modified aqueous battery current collector is obtained.
[0011] The monomer containing a thiol group is selected from one or more of aniline containing a thiol group, pyrrole containing a thiol group, thiophene containing a thiol group, and indole containing a thiol group.
[0012] Considering the numerous problems with current collectors in aqueous ion batteries, this invention utilizes monomers containing thiol groups as raw materials. Thiol groups can form stable chemical bonds with metal current collectors. Leveraging the high binding affinity between thiol groups and metal current collectors, a two-dimensional conductive polymer layer containing thiol groups is formed on the surface of the current collector. This passivates the current collector, reduces water activity, and improves the stability of the current collector in aqueous systems. Furthermore, selecting monomers with different thiol groups can passivate the current collector to varying degrees, increasing the water electrolysis barrier to broaden the electrochemical window, while also preventing rapid metal corrosion and ensuring a certain level of conductivity.
[0013] In the entire preparation process, step S2 becomes the key step affecting product performance. By adding the bicontinuous microemulsion into a high-speed rotating container, the bicontinuous microemulsion completes the polymerization process under the action of centrifugal force and shear force. Specifically, driven by the high-speed rotating container, the bicontinuous microemulsion is completely thrown onto the container wall, meaning there is no bicontinuous microemulsion at the bottom of the container, forming a liquid film of uniform thickness. Due to the different distances from various points in the liquid film to the rotation axis, flow layers with different flow velocities are formed. The difference in flow velocity between the flow layers creates shear flow. Within these shear planes, the shear force along the generatrix direction will dominate the spatial conformational changes of the polymer molecular chains, promoting the chain orientation of conductive polymers along the shear direction. The centrifugal force generated during the rotation process separates and selects various products of the polymerization process according to the fluid volume and mass. Products with high molecular weight will move in the direction away from the rotation axis and eventually deposit on the substrate.
[0014] Furthermore, the monomers containing thiol groups include, but are not limited to, one or more of 2-mercaptobenzene, 4-(vinylthio)aniline, 3-chloro-4-(methylthio)aniline, 2-(isopropylthio)aniline, 2-methyl-5-(methylthio)aniline, N-methyl-4-(methylthio)aniline, 3-mercaptothiophene, 2-thiophene thiol, (R)-4-mercapto-2-pyrrolidone, and 3-mercaptoindole.
[0015] Furthermore, the dopant is selected from one or more of phytic acid, hydrochloric acid, sulfuric acid, dodecylbenzenesulfonic acid, p-toluenesulfonic acid, and camphorsulfonic acid;
[0016] The oxidant is selected from one or more of hydrogen peroxide, ferric chloride, ammonium persulfate, and iodine.
[0017] The concentration of solution A is 10-30 wt%, the concentration of oxidant in solution B is 0.1-0.5 mol / L, and the concentration of dopant is 0.01-0.1 mol / L; the mass ratio of TX-100 to n-butanol in solution C is 1-2:1.
[0018] The volume ratio of solution A, solution B, and solution C is 1-6:1:1-3.
[0019] Furthermore, the molar ratio of the monomer containing the thiol group to the dopant is 1-2:1;
[0020] The molar ratio of the monomer containing the thiol group to the oxidant is 2-5:1.
[0021] In step S2, the container rotation angular velocity is 10000-18000 rpm, and the rotation processing time is 4-10 hours.
[0022] Furthermore, the current collector is selected from one of the following: metal foil materials such as stainless steel foil, titanium foil, copper foil, and aluminum foil; metal mesh materials such as stainless steel mesh, titanium mesh, and copper mesh; and non-metallic materials such as graphite paper, carbon paper, graphite felt, and carbon felt.
[0023] Furthermore, the specific steps of the scraping method are as follows:
[0024] A concentrated solution of two-dimensional conductive polymer nanosheets is poured onto the surface of the current collector, and then coated with a scraper.
[0025] The distance between the scraper and the surface of the current collector is 10-1000 μm.
[0026] Furthermore, the drying temperature is 40-100℃, and the drying time is 2-40h.
[0027] To achieve the second objective mentioned above, the present invention adopts the following technical solution:
[0028] This invention discloses a two-dimensional conductive polymer-modified aqueous battery current collector prepared by the preparation method described above.
[0029] To achieve the third objective mentioned above, the present invention adopts the following technical solution:
[0030] This invention discloses the application of the two-dimensional conductive polymer-modified aqueous battery current collector described above in the preparation of aqueous ion batteries, wherein the aqueous ion battery is selected from Li + Na + K + Ca 2+ Zn 2+ or Mg 2+ Secondary batteries.
[0031] Furthermore, the aqueous ion battery also includes a positive electrode material and a negative electrode material. For example, the positive electrode material can be a Prussian blue analogue, a transition metal oxide, a NASICON fast ion conductor, etc., and the negative electrode material can be one of the following: a metal negative electrode (zinc, copper, etc.), a carbon-based material (activated carbon, etc.), a metal sulfide / selenide (copper sulfide, zinc sulfide, copper selenide, etc.), a metal oxide (vanadium oxide, manganese oxide, etc.), or a non-metallic element (sulfur, selenium, etc.).
[0032] Furthermore, the aqueous ion battery also includes an electrolyte. Exemplarily, the electrolyte may be an aqueous electrolyte containing lithium difluorosulfonate, sodium difluorosulfonate, potassium difluorosulfonate, potassium difluorosulfonate, zinc trifluoromethanesulfonate, magnesium bis(trifluoromethanesulfonyl)imide, or zinc bis(trifluoromethanesulfonyl)imide.
[0033] The beneficial effects of this invention are as follows:
[0034] This invention introduces monomers containing thiol groups to prepare a two-dimensional conductive polymer modification layer for current collectors in aqueous batteries. First, by forming stable chemical bonds between the thiol groups and the metal current collector, the bonding force between the polymer modification layer and the metal current collector is significantly improved, thus eliminating the problems of easy detachment and weak bonding force inherent in conventional conductive polymer layers. Second, this invention uses a bicontinuous microemulsion polymerization method under high centrifugal and shear forces to achieve two-dimensionalization of the conductive polymer, increasing its specific surface area and fully exposing active sites, thereby improving its conductivity and promoting ion transport during battery charging and discharging. Finally, by changing the types of monomers with thiol groups, this invention obtains current collectors with different degrees of passivation, increasing the water electrolysis barrier, widening the electrochemical window, and preventing rapid metal corrosion. Therefore, the preparation method provided by this invention allows the obtained two-dimensional conductive polymer-modified aqueous battery current collector to possess advantages such as strong bonding force, high flexibility, corrosion resistance, high conductivity, strong adhesion, and acid and alkali resistance, broadening the range of current collectors that can be applied in aqueous ion batteries.
[0035] The preparation method provided by this invention has the advantages of being economical, easy to operate, and having outstanding performance, providing a new approach for the development of current collectors in aqueous ion batteries. Attached Figure Description
[0036] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.
[0037] Figure 1 A schematic diagram showing the state of a bicontinuous microemulsion in a container is shown.
[0038] Figure 2 The diagram shows the cycle performance of a zinc / manganese dioxide battery assembled with a stainless steel current collector modified with two-dimensional mercapto-polyaniline prepared by the blade coating method in Example 1 after 1000 charge-discharge cycles. After 1000 charge-discharge cycles at 5C, the full battery still has 95% capacity retention.
[0039] Figure 3 The graph shows the cycle performance of the zinc / manganese dioxide battery assembled with an unmodified two-dimensional mercapto-polyaniline stainless steel current collector as described in Comparative Example 1 after 1000 charge-discharge cycles. This full cell has only 63.8% capacity retention after 1000 charge-discharge cycles at 5C. Detailed Implementation
[0040] To more clearly illustrate the present invention, the following description, in conjunction with preferred embodiments and accompanying drawings, further explains the invention. Similar components in the drawings are indicated by the same reference numerals. Those skilled in the art should understand that the specific description below is illustrative rather than restrictive and should not be construed as limiting the scope of protection of the present invention.
[0041] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.
[0042] To better represent the state of a bicontinuous microemulsion within a high-speed rotating container, this invention provides... Figure 1 Please provide an explanation. Figure 1 Figure 'a' shows a schematic diagram of a bicontinuous microemulsion placed in a stationary container. The container is in an inverted position, meaning its sidewalls are parallel to the horizontal plane. Due to gravity, the bicontinuous microemulsion is concentrated within a limited area on the container's sidewall. Once the container begins to rotate, the bicontinuous microemulsion is driven to flow to other areas on the container's sidewall. Figure 1 In state b, as the rotation speed increases, the bicontinuous microemulsion is completely thrown onto the sidewall of the container and forms a uniform liquid film, i.e. Figure 1 The state of c in the middle.
[0043] Example 1
[0044] The preparation of two-dimensional thiol-modified stainless steel foil by a blade coating method includes the following steps:
[0045] 0.4 g of 2-mercaptoaniline monomer was dissolved in 1.6 g of cyclohexane to form solution A. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The above three solutions were mixed in a volume ratio of 4:3:3 (total volume of 2.5 mL) to form a bicontinuous microemulsion.
[0046] The bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain two-dimensional thiol-based polyaniline nanosheets. The nanosheets were then dispersed in 500 μL of water to form a concentrated solution.
[0047] The obtained concentrated solution of two-dimensional mercapto-polyaniline nanosheets was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then placed in a vacuum oven at 100 °C for vacuum drying for 24 h to obtain a stainless steel current collector modified with two-dimensional mercapto-polyaniline, with a coating thickness of about 50 μm.
[0048] A stainless steel current collector modified with two-dimensional mercapto-polyaniline was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were performed on a Newway electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C. The results are shown below. Figure 2 The initial discharge specific capacity is 200 mAh g.-1 After 1000 charge-discharge cycles, the battery still maintains a capacity of 190mAh. -1 The discharge specific capacity has a cycle retention rate of 95.0%, and the average capacity loss per cycle is as low as 0.005%.
[0049] Example 2
[0050] The preparation of two-dimensional thiol-modified stainless steel foil by a blade coating method includes the following steps:
[0051] 0.4 g of 2-mercaptopyrrole monomer was dissolved in 1.6 g of cyclohexane to form solution A. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The above three solutions were mixed in a volume ratio of 4:3:3 (total volume of 2.5 mL) to form a bicontinuous microemulsion.
[0052] The bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain two-dimensional thiol-based polypyrrole nanosheets. The nanosheets were then dispersed in 500 μL of water to form a concentrated solution.
[0053] The obtained concentrated solution of two-dimensional mercaptopolypyrrole nanosheets was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then placed in a vacuum oven at 100 °C for vacuum drying for 24 h to obtain a stainless steel current collector modified with two-dimensional mercaptopolypyrrole, with a coating thickness of approximately 55 μm.
[0054] A stainless steel current collector modified with two-dimensional mercapto-polypyrrole was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Xinwei electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 195 mAh g⁻¹. -1 After 1000 charge-discharge cycles, the battery still maintains a capacity of 178mAh g. -1 The discharge specific capacity has a cycle retention rate of 91.28%, and the average capacity loss per cycle is as low as 0.009%.
[0055] Example 3
[0056] The preparation of two-dimensional thiol-modified stainless steel foil by a blade coating method includes the following steps:
[0057] 0.4 g of 4-(vinylthio)aniline monomer was dissolved in 1.6 g of cyclohexane. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The above three solutions were mixed in a volume ratio of 4:3:3 (total volume of 2.5 mL) to form a bicontinuous microemulsion.
[0058] The bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain two-dimensional thiol-based polyaniline nanosheets. The nanosheets were then dispersed in 500 μL of water to form a concentrated solution.
[0059] The obtained concentrated solution of two-dimensional mercapto-polyaniline nanosheets was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then placed in a vacuum oven at 100 °C for vacuum drying for 24 h to obtain a stainless steel current collector modified with two-dimensional mercapto-polyaniline, with a coating thickness of about 50 μm.
[0060] A stainless steel current collector modified with two-dimensional mercapto-polyaniline was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Xinwei electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 195 mAh g⁻¹. -1 After 1000 charge-discharge cycles, the battery still maintains a capacity of 188mAh g. -1 The discharge specific capacity has a cycle retention rate of 96.41%, and the average capacity loss per cycle is as low as 0.004%.
[0061] Example 4
[0062] The preparation of two-dimensional thiol-modified stainless steel foil by a blade coating method includes the following steps:
[0063] 0.4 g of N-methyl-4-(methylmercapto)aniline monomer was dissolved in 1.6 g of cyclohexane. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The above three solutions were mixed in a volume ratio of 4:3:3 (total volume of 2.5 mL) to form a bicontinuous microemulsion.
[0064] The bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain two-dimensional thiol-based polyaniline nanosheets. The nanosheets were then dispersed in 500 μL of water to form a concentrated solution.
[0065] The obtained concentrated solution of two-dimensional mercapto-polyaniline nanosheets was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then placed in a vacuum oven at 100 °C for vacuum drying for 24 h to obtain a stainless steel current collector modified with two-dimensional mercapto-polyaniline, with a coating thickness of about 50 μm.
[0066] A stainless steel current collector modified with mercapto-polyaniline was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Newway electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 194 mAh g⁻¹. -1 After 1000 charge-discharge cycles, the battery still maintains a capacity of 186mAh g. -1 The discharge specific capacity has a cycle retention rate of 95.87%, and the average capacity loss per cycle is as low as 0.004%.
[0067] Example 5
[0068] The preparation of two-dimensional mercapto-polythiophene-modified stainless steel foil by a blade coating method includes the following steps:
[0069] 0.4 g of 3-mercaptothiophene monomer was dissolved in 1.6 g of cyclohexane. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The above three solutions were mixed in a volume ratio of 4:3:3 (total volume of 2.5 mL) to form a bicontinuous microemulsion.
[0070] The bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain two-dimensional mercapto-polythiophene nanosheets. The nanosheets were then dispersed in 500 μL of water to form a concentrated solution.
[0071] The obtained two-dimensional mercapto-polythiophene concentrated solution was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then placed in a vacuum oven at 100 °C for 24 h to obtain a stainless steel current collector modified with two-dimensional mercapto-polythiophene and a coating thickness of 55 μm.
[0072] A stainless steel current collector modified with two-dimensional mercapto-polythiophene was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Xinwei electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 201 mAh g / g. -1 After 1000 charge-discharge cycles, the battery still maintains a capacity of 178mAh g. -1 The discharge specific capacity has a cycle retention rate of 88.55%, and the average capacity loss per cycle is as low as 0.011%.
[0073] Example 6
[0074] The preparation of two-dimensional mercapto-polythiophene-modified stainless steel foil by a blade coating method includes the following steps:
[0075] 0.4 g of (R)-4-mercapto-2-pyrrolidone monomer was dissolved in 1.6 g of cyclohexane. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The above three solutions were mixed in a volume ratio of 4:3:3 (total volume of 2.5 mL) to form a bicontinuous microemulsion.
[0076] The bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain two-dimensional mercapto-polythiophene nanosheets. The nanosheets were then dispersed in 500 μL of water to form a concentrated solution.
[0077] The obtained two-dimensional mercapto-polythiophene concentrated solution was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then placed in a vacuum oven at 100 °C for 24 h to obtain a stainless steel current collector modified with two-dimensional mercapto-polythiophene and a coating thickness of 55 μm.
[0078] A stainless steel current collector modified with two-dimensional mercapto-polythiophene was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Newway electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 199 mAh g⁻¹. -1 After 1000 charge-discharge cycles, the battery still maintains a capacity of 176mAh g. -1It has a discharge specific capacity with a cycle retention rate of 88.44% and an average capacity loss of only 0.011% per cycle.
[0079] Comparative Example 1
[0080] The preparation of polypyrrole nanoparticle-modified stainless steel foil by a blade coating method includes the following steps:
[0081] 0.4 g of pyrrole monomer was dissolved in 1.6 mL of water to form solution A, and phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled so that the pH of solution B was between 1 and 2. The two solutions were mixed at a volume ratio of 4:3 and stirred continuously for 6 h to obtain polypyrrole nanoparticles. The nanoparticles were dispersed in 500 μL of water to form a concentrated solution.
[0082] The obtained polypyrrole concentrated solution was poured onto a stainless steel foil, coated with a 500μm doctor blade, and then placed in a vacuum oven at 100℃ for vacuum drying for 24h to obtain a polypyrrole-modified stainless steel current collector with a coating thickness of 50μm.
[0083] A polypyrrole-modified stainless steel current collector was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were performed on a Newway electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C. The results are shown below. Figure 3 The initial discharge specific capacity is 200 mAh g. -1 After 1000 charge-discharge cycles, the battery maintains a capacity of 127.5 mAh g. -1 The discharge specific capacity has a cycle retention rate of 63.8% and an average capacity loss of 0.036% per cycle.
[0084] Comparative Example 2
[0085] The preparation of stainless steel foil modified with thiol-modified polyaniline nanoparticles by a blade coating method includes the following steps:
[0086] Solution A was prepared by dissolving 0.4 g of 2-mercaptoaniline monomer in 1.6 mL of water, and solution B was prepared by dissolving phytic acid and 1.4 g of ammonium persulfate in 10 mL of water. The amount of phytic acid was controlled to maintain the pH of solution B between 1 and 2. The two solutions were mixed at a volume ratio of 4:3 and stirred continuously for 6 h to obtain mercapto-polyaniline nanoparticles. The nanoparticles were dispersed in 500 μL of water to form a concentrated solution. The concentrated mercapto-polyaniline solution was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then vacuum dried in a 100 °C vacuum oven for 24 h to obtain a 50 μm thick stainless steel current collector modified with mercapto-polyaniline.
[0087] A stainless steel current collector modified with mercapto-polyaniline was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Newway electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 197 mAh g⁻¹. -1 After 1000 charge-discharge cycles, the battery retains 128mAh g. -1 The discharge specific capacity has a cycle retention rate of 64.97%, and the average capacity loss per cycle is 0.035%.
[0088] Comparative Example 3
[0089] The preparation of two-dimensional polyaniline-modified stainless steel foil by a blade coating method includes the following steps:
[0090] 0.4 g of aniline monomer was dissolved in 1.6 g of cyclohexane. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The above three solutions were mixed in a volume ratio of 4:3:3 (total volume of 2.5 mL) to form a bicontinuous microemulsion.
[0091] A bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain two-dimensional polyaniline nanosheets. The nanosheets were then dispersed in 500 μL of water to form a concentrated solution. The resulting concentrated two-dimensional polyaniline solution was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then vacuum-dried in a 100℃ vacuum oven for 24 hours to obtain a two-dimensional polyaniline-modified stainless steel current collector with a coating thickness of 50 μm.
[0092] A two-dimensional polyaniline-modified stainless steel current collector was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Newway electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 199 mAh g⁻¹. -1 After 1000 charge-discharge cycles, the battery retains 135mAh g. -1 The discharge specific capacity has a cycle retention rate of 67.83%, and the average capacity loss per cycle is 0.032%.
[0093] Comparative Example 4
[0094] The preparation of stainless steel foil modified with thiol-modified polyaniline nanoparticles by a blade coating method includes the following steps:
[0095] 0.4 g of 2-mercaptoaniline monomer was dissolved in 1.6 mL of cyclohexane to form solution A. Phytic acid and 1.4 g of ammonium persulfate were dissolved in 10 mL of water to form solution B. The amount of phytic acid was controlled to keep the pH of solution B between 1 and 2. TX-100 and n-butanol were mixed in a mass ratio of 1:1 to form solution C. The three solutions were mixed in a volume ratio of 3:2:5 to form a bicontinuous microemulsion.
[0096] A bicontinuous microemulsion was poured into a high-speed rotating container at 12,000 rpm and centrifuged for 6 hours to obtain mercapto-polyaniline nanoparticles. The nanoparticles were then dispersed in 500 μL of water to form a concentrated solution. The resulting concentrated mercapto-polyaniline solution was poured onto a stainless steel foil, coated with a 500 μm doctor blade, and then vacuum-dried in a 100°C vacuum oven for 24 hours to obtain a mercapto-polyaniline-modified stainless steel current collector with a coating thickness of 50 μm.
[0097] A stainless steel current collector modified with mercapto-polyaniline was used to prepare manganese dioxide electrodes, which were then assembled into zinc / manganese dioxide batteries. The electrolyte consisted of 2M ZnSO4 + 0.1M MnSO4, and deionized water was used for preparation. A GF / F separator was used, and the coin cell casing was made of CR2032. Cyclic stability tests were conducted on a Newway electrochemical testing cabinet. This invention selected 1000 charge-discharge cycles at a high rate of 5C, and the initial discharge specific capacity was 194 mAh g⁻¹. -1 After 1000 charge-discharge cycles, the battery retains 133mAh g. -1 The discharge specific capacity has a cycle retention rate of 68.56%, and the average capacity loss per cycle is 0.031%.
[0098] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.
Claims
1. A method for preparing a two-dimensional conductive polymer-modified aqueous battery current collector, characterized in that, Includes the following steps: S1. Dissolve the monomer containing thiol groups in cyclohexane to form solution A, dissolve the dopant and oxidant in water to form solution B, mix the nonionic surfactant TX-100 and the co-surfactant n-butanol to form solution C, and mix the above three solutions to obtain a bicontinuous microemulsion. S2. Pour the bicontinuous microemulsion into a high-speed rotating container, so that the bicontinuous microemulsion in the container forms a uniform liquid film with a thickness of 500-1000 μm on the side wall of the container and polymerizes it to obtain two-dimensional conductive polymer nanosheets. S3. Two-dimensional conductive polymer nanosheets are modified onto the surface of the current collector using a blade coating method, and after drying, a two-dimensional conductive polymer modified aqueous battery current collector is obtained. The monomer containing a thiol group is selected from one or more of aniline containing a thiol group, pyrrole containing a thiol group, thiophene containing a thiol group, and indole containing a thiol group.
2. The preparation method according to claim 1, characterized in that, The monomer containing a thiol group is selected from one or more of 2-mercaptobenzene, 4-(vinylthio)aniline, 3-chloro-4-(methylthio)aniline, 2-(isopropylthio)aniline, 2-methyl-5-(methylthio)aniline, N-methyl-4-(methylthio)aniline, 3-mercaptothiophene, 2-thiophene thiol, (R)-4-mercapto-2-pyrrolidone, and 3-mercaptoindole.
3. The preparation method according to claim 1, characterized in that, The dopant is selected from one or more of phytic acid, hydrochloric acid, sulfuric acid, dodecylbenzene sulfonic acid, p-toluene sulfonic acid, and camphor sulfonic acid; The oxidant is selected from one or more of hydrogen peroxide, ferric chloride, ammonium persulfate, and iodine.
4. The preparation method according to claim 1, characterized in that, The concentration of solution A is 10-30 wt%, the concentration of oxidant in solution B is 0.1-0.5 mol / L, and the concentration of dopant is 0.01-0.1 mol / L; the mass ratio of TX-100 to n-butanol in solution C is 1-2:
1. The volume ratio of solution A, solution B, and solution C is 1-6:1:1-3.
5. The preparation method according to claim 1, characterized in that, The molar ratio of the monomer containing a thiol group to the dopant is 1-2:1; The molar ratio of the monomer containing the thiol group to the oxidant is 2-5:
1.
6. The preparation method according to claim 1, characterized in that, In step S2, the container rotation angular velocity is 10000-18000 rpm, and the rotation processing time is 4-10 hours.
7. The preparation method according to claim 1, characterized in that, The current collector is selected from one of the following: stainless steel foil, titanium foil, copper foil, aluminum foil, stainless steel mesh, titanium mesh, copper mesh, graphite paper, carbon paper, graphite felt, and carbon felt.
8. The preparation method according to claim 1, characterized in that, The specific steps of the scraping method are as follows: A concentrated solution of two-dimensional conductive polymer nanosheets is poured onto the surface of the current collector, and then coated with a scraper. The distance between the scraper and the surface of the current collector is 10-1000 μm.
9. The two-dimensional conductive polymer-modified aqueous battery current collector prepared by the preparation method according to any one of claims 1-7.
10. The application of two-dimensional conductive polymer-modified aqueous battery current collector in the preparation of aqueous ion batteries, characterized in that, The aqueous ion battery is selected from Li + Na + K + Ca 2+ Zn 2+ or Mg 2+ Secondary batteries.