A fully gel-type zinc-air button battery and its preparation method

Abstract

The present invention discloses a fully gel-type button zinc-air battery and a preparation method thereof, belonging to the technical field of zinc-air batteries. The preparation method is as follows: water is added to acrylamide, and then a conductive active substance or a conductive polymer, a pore former, and a binder are added and stirred evenly. Then, a cross-linking agent, an initiator, and a catalyst are added to obtain a mixed solution I, which is poured into a mold I and dried to obtain a dehydrated positive gel sheet; water is added to acrylamide, and then a cross-linking agent, an initiator, and a catalyst are added to obtain a mixed solution II, which is poured into a mold II and dried to obtain a gel thin sheet, and then the gel thin sheet is soaked in an alkaline zinc salt electrolyte to obtain a gel electrolyte thin sheet; a platinum-carbon catalyst is dropped onto the upper surface of the dehydrated positive gel sheet, and then interfacial dry cross-linking is carried out with the gel electrolyte thin sheet to obtain a fully gel-type button integrated thin sheet; a negative electrode case, a zinc negative electrode sheet, the fully gel-type button integrated thin sheet, and an air positive electrode case are stacked from bottom to top in sequence and then encapsulated to obtain the target product.

Description

Technical Field

[0001] The present invention belongs to the technical field of zinc-air batteries, and particularly relates to a fully-gelled button zinc-air battery and a preparation method thereof. Background Art

[0002] Zinc-air batteries have the advantages of large specific capacity, high specific energy, stable discharge performance, cheap and easily available raw materials, and no environmental pollution during production and use. For small or micro electrical appliances, button zinc-air batteries have great development prospects. Because they only use oxygen in the air as the positive electrode material with an unlimited source, and the capacity of button zinc-air batteries is 3-5 times higher than that of other batteries. Such batteries also have the advantages of stable working voltage and low noise, so they have great development prospects. However, there are still problems such as small discharge current density, liquid leakage and alkali creep, and electrolyte carbonation. Summary of the Invention

[0003] In order to overcome the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a fully-gelled button zinc-air battery and a preparation method thereof, so as to solve the technical problems of small discharge current density, liquid leakage and alkali creep, and electrolyte carbonation in the present. The operation of the preparation method is simple and fast, which can improve the battery assembly efficiency, and also makes the battery use less electrolyte, safer and not easy to leak.

[0004] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0005] The present invention provides a preparation method of a fully-gelled zinc-air button battery, including the following steps:

[0006] S1: Add water to the acrylamide matrix and stir, then add a conductive active substance or a conductive polymer, a pore-forming agent, and a binder and stir evenly. Then add a cross-linking agent, an initiator, and a catalyst to obtain a mixed solution I. Inject the mixed solution I into mold I and dry it to obtain a dehydrated positive electrode gel sheet 4;

[0007] S2: Add water to the acrylamide matrix and stir, then add a cross-linking agent, an initiator, and a catalyst to obtain a mixed solution II. Inject the mixed solution II into mold II and dry it to obtain a gel thin sheet. Then soak the gel thin sheet in an alkaline zinc salt electrolyte to obtain a gel electrolyte thin sheet 3;

[0008] S3: Drop a platinum-carbon catalyst on the upper surface of the dehydrated positive electrode gel sheet 4 and perform interfacial dry cross-linking with the gel electrolyte thin sheet 3 to obtain a fully-gelled button integrated thin sheet;

[0009] S4: Stack the negative electrode shell 1, the zinc negative electrode sheet 2, the fully-gelled button integrated thin sheet, and the air positive electrode shell 5 from bottom to top in sequence and encapsulate them to obtain a fully-gelled zinc-air button battery.

[0010] Further, in the present invention, the crosslinking agent is N,N'-methylenebisacrylamide; the catalyst is tetramethylethylenediamine; the initiator is one of ammonium persulfate or potassium persulfate.

[0011] Further, in the present invention, in S1, the conductive active material is one of carbon nanotubes, conductive carbon, and graphene; the conductive polymer is one of polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene).

[0012] Further, in the present invention, in S1, the pore-forming agent is one of polyethylene glycol-600 or polyethylene glycol-1000; the binder is one of carboxymethyl cellulose or sodium carboxymethyl cellulose.

[0013] Further, in the present invention, in S1, the mass ratio of acrylamide, conductive active material or conductive polymer, water, pore-forming agent, binder, crosslinking agent, catalyst, and initiator in the dehydrated positive gel sheet 4 is 1:(0.02 - 0.03):(2.5 - 3):(0.12 - 0.15):(0.025 - 0.03):(0.00025 - 0.0003):(0.001 - 0.0015):(0.007 - 0.0073).

[0014] Further, in the present invention, in S2, the mass ratio of acrylamide, water, crosslinking agent, catalyst, and initiator in the gel electrolyte thin sheet (3) is 1:(2.5 - 3):(0.00025 - 0.0003):(0.001 - 0.0015):(0.007 - 0.0073).

[0015] Further, in the present invention, in S2, the alkaline zinc salt electrolyte is a compound solution of potassium hydroxide and zinc acetate; the mass ratio of potassium hydroxide to zinc acetate is (7 - 8:1); the soaking time is 72h - 96h.

[0016] Further, in the present invention, in S1, the mold I is a circular thin sheet mold with a diameter of 10 - 12 mm; in S2, the mold II is a circular thin sheet mold with a diameter of 12 - 14 mm; the diameter of the mold II is greater than that of the mold I.

[0017] Further, in the present invention, in S3, the platinum-carbon catalyst is a compound solution composed of platinum-carbon, isopropanol, and Nafion solution; the dosage of platinum-carbon is 1 - 1.5 mg / cm 2 , and the mass ratio of isopropanol to Nafion solution is (20 - 24):1.

[0018] The present invention discloses a fully gel zinc-air button battery prepared by using the preparation method described in any one of the above.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention provides a preparation method of a fully-gelled zinc-air button battery. The positive gel sheet and the alkaline gel electrolyte are bonded in the form of interfacial dry crosslinking. The dehydrated positive gel sheet will spontaneously absorb moisture from the alkaline gel electrolyte, thereby spontaneously generating hydrogen bonds to connect the positive gel sheet and the gel electrolyte. And the principle of spontaneous hydrogen bond connection can greatly improve the manufacturing efficiency of manufacturers. The preparation method is simple and fast, can improve the battery assembly efficiency, and does not use complex physical and chemical technologies for preparation.

[0021] For the battery obtained by using the preparation method of the fully-gelled zinc-air button battery of the present invention, first of all, the positive gel sheet and the alkaline gel electrolyte are integrated, and the separator required for the preparation of traditional button batteries is not needed, avoiding the interface between the electrode and the separator, reducing the contact impedance between the interfaces, improving the electrochemical performance of the battery, and the network structure of the electrolyte gel makes it not easy to leak liquid, solving the problems of liquid leakage and alkali creep, electrolyte carbonation, etc. of current traditional button batteries, making the battery more firm, reliable and safe. Secondly, since both the positive gel sheet and the gel electrolyte thin sheet have a network structure, it increases the positive material loading area and speeds up the charge transfer rate, thereby improving the areal energy density and volumetric energy density of the battery.

[0022] Furthermore, traditional button batteries use the method of dropping electrolyte, while the fully-gelled zinc-air button battery of the present invention, because it uses a gel electrolyte, its network structure firmly locks the electrolyte in the gel, thus there are no problems such as liquid leakage and alkali creep, electrolyte carbonation, etc. The active substances in the positive gel sheet use materials such as carbon nanotubes, graphene, conductive polymers, etc. with excellent electrical and thermal conductivity. The combination of active substances with excellent electrical conductivity and the water gel with a network structure as the path greatly increases the positive loading area and speeds up the charge transfer rate, thereby solving the problem of small discharge current density and obtaining a battery with high areal energy density and high volumetric energy density. Using the form of dry crosslinking to bond the electrolyte gel and the positive gel sheet to form a fully-gelled button zinc-air battery not only makes the battery have excellent electrochemical performance, but also makes the battery more firm and safer. Brief Description of the Drawings

[0023] Figure 1 is an assembly schematic diagram of the zinc-air button battery of the present invention;

[0024] Figure 2 is the discharge curve graph of the zinc-air fully-gelled button battery assembled in Example 1 of the present invention at a current of 2 mA cm -2 ;

[0025] Figure 3 The discharge curve of the zinc-air all-gel button battery assembled in Example 2 of the present invention under a current of 2 mA cm -2 .

[0026] Wherein: 1 - negative electrode case; 2 - zinc negative electrode sheet; 3 - gel electrolyte sheet; 4 - positive electrode gel sheet; 5 - air positive electrode case. Detailed implementation manners

[0027] To enable those skilled in the art to understand the features and effects of the present invention, the following provides a general description and definition of the terms and phrases mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used herein shall have the ordinary meaning understood by those skilled in the art with respect to the present invention. In case of conflict, the definition in this specification shall prevail.

[0028] The theories or mechanisms described and disclosed herein, whether correct or incorrect, shall in no way limit the scope of the present invention, that is, the content of the present invention can be implemented without being limited by any specific theory or mechanism.

[0029] In this article, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are only for the sake of brevity and convenience. Accordingly, the description of numerical ranges or percentage ranges should be regarded as having covered and specifically disclosed all possible sub-ranges and individual numerical values within the range (including integers and fractions).

[0030] In this article, unless otherwise specified, the terms "comprising", "including", "containing", "having", or similar terms cover the meanings of "consisting of" and "consisting essentially of". For example, "A comprises a" covers the meanings of "A comprises a and others" and "A only comprises a".

[0031] In this article, for the sake of brevity of description, all possible combinations of all technical features in each embodiment or example are not described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered to be within the scope described in this specification.

[0032] The present invention provides an all-gel button zinc-air battery and a preparation method thereof.

[0033] The following further elaborates the present invention in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

[0034] In the following examples, conventional instruments and equipment in the art are used. For the experimental methods without specific conditions indicated in the following examples, they are generally carried out under conventional conditions or according to the conditions recommended by the manufacturer. In the following examples, various raw materials are used. Unless otherwise specified, commercially available products are used, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" represents weight percentage, "parts" represents weight parts, and the ratio represents weight ratio.

[0035] The present invention discloses a preparation method of a fully gel zinc-air button battery, and the specific steps are as follows:

[0036] Step 1: Prepare an alkaline zinc salt electrolyte and a dry and clean negative electrode case, a zinc negative electrode sheet, and an air positive electrode case;

[0037] Step 2: Prepare a dehydrated positive electrode gel sheet 3:

[0038] The positive electrode hydrogel is based on acrylamide, added with a conductive active substance / conductive polymer, and then added with a pore-forming agent polyethylene glycol PEG-1000, a binder carboxymethyl cellulose, a cross-linking agent N,N'-methylenebisacrylamide, a catalyst tetramethylethylenediamine, and an initiator ammonium persulfate. The positive electrode gel film is prepared by injecting it into a circular polytetrafluoroethylene thin film mold I with a diameter of 10-12 mm, and then dried in an oven at 60-80 °C to obtain a dehydrated positive electrode gel sheet 4.

[0039] As an alternative, the conductive active substance is one of carbon nanotubes, conductive carbon, and graphene; the conductive polymer is one of polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene).

[0040] The pore-forming agent is one of polyethylene glycol-600 or polyethylene glycol-1000; the binder is one of carboxymethyl cellulose or sodium carboxymethyl cellulose.

[0041] Step 3: Preparation of the gel electrolyte: Take a certain amount of acrylamide. After starting stirring, sequentially add the cross-linking agent N,N'-methylenebisacrylamide, the initiator ammonium persulfate, and the catalyst tetramethylethylenediamine to it, stir for 30-40 min, then drop the obtained solution into a circular polytetrafluoroethylene thin film mold II with a diameter of 12-14 mm, and then place it in a constant temperature oven at 60-70 °C to obtain a gel thin film. Immerse it in the alkaline zinc salt electrolyte to obtain an alkaline gel electrolyte sheet, and cut it to obtain one or more circular gel electrolyte thin sheets 3 with a diameter of 12-14 mm;

[0042] The diameter of the mold II is larger than that of the mold I.

[0043] Step 4: Obtain a fully-gelled button-shaped integrated thin sheet by means of interfacial dry crosslinking of the dehydrated positive electrode gel sheet and the alkaline gel electrolyte thin sheet;

[0044] Step 5: First stack the negative electrode case 1, zinc negative electrode sheet 2, fully-gelled button-shaped integrated thin sheet, dropwise add the catalyst, and air positive electrode case 5 from bottom to top in sequence, and finally use a battery encapsulation press to press and encapsulate to obtain a fully-gelled zinc-air button battery.

[0045] As a further improvement of the present invention, the crosslinking agent is N,N'-methylenebisacrylamide; the catalyst is tetramethylethylenediamine; the initiator is one of ammonium persulfate or potassium persulfate.

[0046] As a further improvement of the present invention, in Step 2, the mass ratio of acrylamide, conductive active substance or conductive polymer, water, pore-forming agent, binder, crosslinking agent, catalyst and initiator in the dehydrated positive electrode gel sheet 4 is 1:(0.02 - 0.03):(2.5 - 3):(0.12 - 0.15):(0.025 - 0.03):(0.00025 - 0.0003):(0.001 - 0.0015):(0.007 - 0.0073). The crosslinking reaction is carried out in a constant temperature oven at a temperature of 50 - 60 °C, and the time of the crosslinking reaction is 20 min - 30 min.

[0047] As a further improvement of the present invention, in Step 3, the mass ratio of acrylamide, water, crosslinking agent N,N'-methylenebisacrylamide, catalyst and initiator in the gel electrolyte thin sheet 3 is 1:(2.5 - 3):(0.00025 - 0.0003):(0.001 - 0.0015):(0.007 - 0.0073). The crosslinking reaction is carried out in a constant temperature oven at a temperature of 60 - 70 °C, and the time of the crosslinking reaction is 20 min - 30 min.

[0048] As a further improvement of the present invention, in Step 3, the alkaline zinc salt electrolyte is a compound solution composed of 6 M / L potassium hydroxide and 0.2 M / L zinc acetate; the dosage of the alkaline zinc salt electrolyte is 250 ml; the mass ratio of potassium hydroxide to zinc acetate is (7 - 8:1); the soaking time is 72 h - 96 h.

[0049] The platinum-carbon catalyst is a compound solution composed of platinum-carbon (catalyst), isopropanol (dispersant) and Nafion solution (ionic polymer); the preparation dosage of platinum-carbon is 1 - 1.5 mg / cm 2 , and the mass ratio of isopropanol to Nafion solution with a concentration of 5 wt% is (20 - 24):1.

[0050] Example 1

[0051] A kind of all-gel zinc-air button battery of the present invention and its preparation method, comprising the following steps:

[0052] (1) Put the negative electrode case and the air positive electrode case into a beaker, add anhydrous ethanol to submerge them, put them into an ultrasonic cleaner and shake for 30 min to obtain clean negative electrode case and air positive electrode case, and put them into an oven at 60 °C to obtain dry and clean negative electrode case and air positive electrode case;

[0053] (2) Add 1.75 g of acrylamide to 5 g of ultrapure water and stir well. Slowly add 0.05 g of graphene, 0.25 g of polyethylene glycol-1000, and 0.05 g of sodium carboxymethyl cellulose during normal temperature stirring, and stir at normal temperature for 20 min. Add 0.0025 g of tetramethylethylenediamine, 0.0005 g of N,N'-methylenebisacrylamide, and 0.0125 g of ammonium persulfate to the above solution in sequence, stir for 30 min to obtain a mixed solution, inject this mixed solution into a circular thin film mold with a diameter of 10 mm, put it into an oven at 60 °C to react for 20 min and then dehydrate for 20 min to obtain a dehydrated positive electrode gel thin film.

[0054] (3) Add 3.5 g of acrylamide to 10 g of ultrapure water and stir well. Slowly add 0.005 g of tetramethylethylenediamine, 0.001 g of N,N'-methylenebisacrylamide, and 0.025 g of ammonium persulfate during normal temperature stirring, stir for 30 min to obtain a mixed solution, inject this mixed solution into a circular thin film mold with a diameter of 14 mm, and put it into an oven at 60 °C to react for 20 min to obtain a gel thin film.

[0055] (4) Immerse the prepared gel polymer in 20 mL of strong base electrolyte for 72 h to obtain a polymer gel electrolyte thin film (alkaline gel electrolyte thin film) with high ionic conductivity, and then cut it into an alkaline gel electrolyte disc with a diameter of 14 mm. The dehydrated positive electrode gel sheet is bonded by interfacial dry crosslinking to obtain an all-gel button integrated thin film.

[0056] (5) The structure of the zinc-air button battery assembled above is: including a negative electrode case 1, a zinc negative electrode sheet 2, an all-gel button integrated thin film formed by dry crosslinking and bonding of a positive electrode gel sheet 4 and a gel electrolyte thin film 3, a catalyst is dripped, and an air positive electrode case 5, which are stacked vertically in alignment from bottom to top. When stacking, the centers of all components are vertically aligned.

[0057] Example 2

[0058] A kind of all-gel zinc-air button battery of the present invention and its preparation method, comprising the following steps:

[0059] (1) Place the negative electrode case and the air positive electrode case into a beaker, add anhydrous ethanol to submerge them, place them in an ultrasonic cleaner and shake for 30 minutes. Then, obtain clean negative electrode case and air positive electrode case, and place them in an oven at 60 °C to obtain dry and clean negative electrode case and air positive electrode case;

[0060] (2) Add 3.5 g of acrylamide to 10 g of ultrapure water and stir well. Then, slowly add 0.1 g of carbon nanotubes, 0.5 g of polyethylene glycol - 1000, and 0.1 g of sodium carboxymethylcellulose under normal temperature stirring, and stir at normal temperature for 20 minutes. Next, add 0.005 g of tetramethylethylenediamine, 0.001 g of N,N’ - methylenebisacrylamide, and 0.025 g of ammonium persulfate to the above solution in sequence, stir for 30 minutes to obtain a mixed solution. Inject this mixed solution into a circular thin - film mold with a diameter of 10 mm, place it in an oven at 60 °C to react for 20 minutes and then dehydrate for 20 minutes to obtain a dehydrated positive electrode gel thin - film.

[0061] (3) Add 7 g of acrylamide to 20 g of ultrapure water and stir well. Then, slowly add 0.01 g of tetramethylethylenediamine, 0.002 g of N,N’ - methylenebisacrylamide, and 0.05 g of ammonium persulfate under normal temperature stirring, stir for 30 minutes to obtain a mixed solution. Inject this mixed solution into a circular thin - film mold with a diameter of 14 mm, place it in an oven at 60 °C to react for 20 minutes to obtain a gel thin - film.

[0062] (4) Immerse the prepared gel polymer in 20 mL of strong - base electrolyte for 72 hours to obtain a polymer gel electrolyte thin - film with high ionic conductivity (alkaline gel electrolyte thin - film). Then, cut it into an alkaline gel electrolyte disc with a diameter of 14 mm. The dehydrated positive electrode gel sheet is bonded through interfacial dry cross - linking to obtain a fully - gel button - type integrated thin - film.

[0063] (5) The structure of the zinc - air button - type battery assembled above is as follows: It includes a negative electrode case 1, a zinc negative electrode sheet 2, a fully - gel button - type integrated thin - film formed by dry cross - linking and bonding of a positive electrode gel sheet 4 and a gel electrolyte thin - film 3, a catalyst is dripped, and an air positive electrode case 5, which are stacked from bottom to top in sequence. When stacking, the centers of all components are vertically aligned.

[0064] Example 3

[0065] A fully - gel zinc - air button - type battery and its preparation method according to the present invention include the following steps:

[0066] (1) Place the negative electrode case and the air positive electrode case into a beaker, add anhydrous ethanol to submerge them, place them in an ultrasonic cleaner and shake for 30 minutes. Then, obtain clean negative electrode case and air positive electrode case, and place them in an oven at 60 °C to obtain dry and clean negative electrode case and air positive electrode case;

[0067] (2) Add 7 g of acrylamide to 20 g of ultrapure water and stir well. Then, slowly add 0.2 g of polyaniline, 1 g of polyethylene glycol - 1000, and 0.2 g of carboxymethyl cellulose while stirring at room temperature, and stir for 20 min at room temperature. Next, add 0.01 g of tetramethylethylenediamine, 0.002 g of N,N'-methylenebisacrylamide, and 0.05 g of potassium persulfate to the above solution in sequence. After stirring for 30 min, a mixed solution is obtained. Inject this mixed solution into a circular thin - film mold with a diameter of 10 mm, place it in an oven at 60 °C for 25 min, and then dehydrate for 20 min to obtain a dehydrated positive - electrode gel thin - film.

[0068] (3) Add 14 g of acrylamide to 40 g of ultrapure water and stir well. Then, slowly add 0.02 g of tetramethylethylenediamine, 0.004 g of N,N'-methylenebisacrylamide, and 0.1 g of potassium persulfate while stirring at room temperature. After stirring for 30 min, a mixed solution is obtained. Inject this mixed solution into a circular thin - film mold with a diameter of 14 mm, place it in an oven at 60 °C for 25 min to obtain a gel thin - film.

[0069] (4) Immerse the prepared gel polymer in 20 mL of strong - base electrolyte for 72 h to obtain a polymer gel electrolyte thin - film with high ionic conductivity (alkaline gel electrolyte thin - film). Then, cut it into circular alkaline gel electrolyte discs with a diameter of 14 mm. Bond the dehydrated positive - electrode gel sheets through interfacial dry cross - linking to obtain an all - gel button - type integrated thin - film.

[0070] (5) The structure of the zinc - air button - type battery assembled above is as follows: It includes a negative - electrode case 1, a zinc negative - electrode sheet 2, an all - gel button - type integrated thin - film formed by dry cross - linking and bonding a positive - electrode gel sheet 4 and a gel electrolyte thin - film 3, a catalyst is dripped, and an air positive - electrode case 5, which are stacked from bottom to top in sequence. When stacking, the centers of all components are vertically aligned.

[0071] Example 3

[0072] A kind of all - gel zinc - air button - type battery and its preparation method of the present invention include the following steps:

[0073] (1) Put the negative - electrode case and the air positive - electrode case into a beaker, add anhydrous ethanol to submerge them, place them in an ultrasonic cleaner and shake for 30 min to obtain clean negative - electrode case and air positive - electrode case, and then place them in an oven at 60 °C to obtain dry and clean negative - electrode case and air positive - electrode case;

[0074] (2) After adding 7 g of acrylamide to 20 g of ultrapure water and stirring well, slowly add 0.2 g of polyaniline, 1 g of polyethylene glycol - 1000, and 0.2 g of carboxymethyl cellulose during stirring at room temperature, and stir at room temperature for 20 min. Then, sequentially add 0.01 g of tetramethylethylenediamine, 0.002 g of N,N’-methylenebisacrylamide, and 0.05 g of potassium persulfate to the above solution. After stirring for 30 min, a mixed solution is obtained. Inject this mixed solution into a circular thin - film mold with a diameter of 10 mm, place it in an oven at 60 °C for reaction for 25 min and then dehydrate for 20 min to obtain a dehydrated positive - electrode gel thin - film.

[0075] (3) After adding 14 g of acrylamide to 40 g of ultrapure water and stirring well, slowly add 0.02 g of tetramethylethylenediamine, 0.004 g of N,N’-methylenebisacrylamide, and 0.1 g of potassium persulfate during stirring at room temperature. After stirring for 30 min, a mixed solution is obtained. Inject this mixed solution into a circular thin - film mold with a diameter of 14 mm, place it in an oven at 60 °C for reaction for 25 min to obtain a gel thin - film.

[0076] (4) Immerse the prepared gel polymer in 20 mL of strong - base electrolyte for 72 h to obtain a polymer gel electrolyte thin - film (alkaline gel electrolyte thin - film) with high ionic conductivity. Then, cut it into a circular alkaline gel electrolyte with a diameter of 14 mm. The dehydrated positive - electrode gel sheet is bonded through interfacial dry cross - linking to obtain a fully - gel button - type integrated thin - film.

[0077] (5) The structure of the zinc - air button - type battery assembled above is as follows: It includes a negative - electrode shell 1, a zinc negative - electrode sheet 2, a fully - gel button - type integrated thin - film formed by dry - cross - linking and bonding a positive - electrode gel sheet 4 and a gel electrolyte thin - film 3, a catalyst is dripped, and an air positive - electrode shell 5, which are stacked from bottom to top in sequence. When stacking, the centers of all components are vertically aligned.

[0078] Example 4

[0079] A fully - gel zinc - air button - type battery and its preparation method according to the present invention include the following steps:

[0080] (1) Put the negative - electrode shell and the air positive - electrode shell into a beaker, add anhydrous ethanol to submerge them, place them in an ultrasonic cleaner and shake for 30 min to obtain clean negative - electrode shell and air positive - electrode shell, and then place them in an oven at 60 °C to obtain a dry and clean negative - electrode shell and air positive - electrode shell;

[0081] (2) After adding 8.75 g of acrylamide to 25 g of ultrapure water and stirring well, slowly dropwise add 0.25 g of polypyrrole, 1.25 g of polyethylene glycol-1000, and 0.25 g of sodium carboxymethylcellulose during stirring at room temperature, and stir at room temperature for 20 min. Then, sequentially add 0.0125 g of tetramethylethylenediamine, 0.0025 g of N,N'-methylenebisacrylamide, and 0.0625 g of ammonium persulfate to the above solution, stir for 30 min to obtain a mixed solution, inject this mixed solution into a circular thin film mold with a diameter of 12 mm, place it in an oven at 60 °C for reaction for 30 min and then dehydrate for 20 min to obtain a dehydrated positive electrode gel thin film.

[0082] (3) After adding 17.5 g of acrylamide to 50 g of ultrapure water and stirring well, slowly dropwise add 0.025 g of tetramethylethylenediamine, 0.005 g of N,N'-methylenebisacrylamide, and 0.125 g of ammonium persulfate during stirring at room temperature, stir for 30 min to obtain a mixed solution, inject this mixed solution into a circular thin film mold with a diameter of 13 mm, place it in an oven at 60 °C for reaction for 30 min to obtain a gel thin film.

[0083] (4) Immerse the prepared gel polymer in 20 mL of strong base electrolyte for 72 h to obtain a polymer gel electrolyte thin film (alkaline gel electrolyte thin film) with high ionic conductivity, and then cut it into an alkaline gel electrolyte disc with a diameter of 13 mm. The dehydrated positive electrode gel sheet is bonded by interfacial dry crosslinking to obtain a fully gel button-type integrated thin film.

[0084] (5) The structure of the zinc-air button battery assembled above is as follows: It includes a negative electrode case 1, a zinc negative electrode sheet 2, a fully gel button-type integrated thin film formed by dry crosslinking and bonding of a positive electrode gel sheet 4 and a gel electrolyte thin film 3, a catalyst is dripped, and an air positive electrode case 5, which are stacked from bottom to top in sequence. When stacking, the centers of all components are vertically aligned.

[0085] Example 5

[0086] A fully gel zinc-air button battery and its preparation method of the present invention include the following steps:

[0087] (1) Put the negative electrode case and the air positive electrode case into a beaker, add anhydrous ethanol to immerse them, place them in an ultrasonic cleaner and shake for 30 min to obtain clean negative electrode case and air positive electrode case, and then place them in an oven at 60 °C to obtain a dry and clean negative electrode case and air positive electrode case;

[0088] (2) After adding 10.5 g of acrylamide to 30 g of ultrapure water and stirring well, 0.33 g of poly(3,4-ethylenedioxythiophene), 1.5 g of polyethylene glycol-600, and 0.3 g of sodium carboxymethylcellulose were slowly added dropwise during stirring at room temperature. Stir at room temperature for 20 min. Then, 0.015 g of tetramethylethylenediamine, 0.003 g of N,N’-methylenebisacrylamide, and 0.075 g of ammonium persulfate were successively added to the above solution. After stirring for 30 min, a mixed solution was obtained. This mixed solution was injected into a circular thin film mold with a diameter of 12 mm, placed in an oven at 60 °C for reaction for 30 min, and then dehydrated for 20 min to obtain a dehydrated positive electrode gel thin film.

[0089] (3) After adding 21 g of acrylamide to 60 g of ultrapure water and stirring well, 0.03 g of tetramethylethylenediamine, 0.003 g of N,N’-methylenebisacrylamide, and 0.15 g of ammonium persulfate were slowly added dropwise during stirring at room temperature. After stirring for 30 min, a mixed solution was obtained. This mixed solution was injected into a circular thin film mold with a diameter of 13 mm and placed in an oven at 60 °C for reaction for 30 min to obtain a gel thin film.

[0090] (4) The prepared gel polymer was immersed in 20 mL of strong base electrolyte for 72 h to obtain a polymer gel electrolyte thin film with high ionic conductivity (alkaline gel electrolyte thin film). Then, it was cut into an alkaline gel electrolyte disc with a diameter of 13 mm. The dehydrated positive electrode gel sheet was bonded by interfacial dry crosslinking to obtain a fully gel button-type integrated thin film.

[0091] (5) The structure of the zinc-air button battery assembled above is as follows: It includes a negative electrode case 1, a zinc negative electrode sheet 2, a fully gel button-type integrated thin film formed by dry crosslinking and bonding of a positive electrode gel sheet 4 and a gel electrolyte thin film 3, a catalyst added dropwise, and an air positive electrode case 5, which are stacked from bottom to top in sequence. When stacking, the centers of all components are vertically aligned.

[0092] As Figure 2 、 3 shown, it can be clearly compared from the two figures that at the current intensity of 2 mA cm -2 , the electrochemical performance of the fully gel button-type battery assembled in Example 2 is better than that in Example 1, with a higher voltage and capacitance. The voltage of Example 2 is basically stable at about 1.2 V, while the voltage of Example 1 is below 1.0 V. The capacitance of Example 2 is 107 mAh, and the capacitance of Example 1 is 70 mAh.

[0093] The all-gel zinc-air button battery described in the present invention uses a gel electrolyte with a network structure that firmly locks the electrolyte into the gel, solving problems such as electrolyte leakage, electrolyte carbonation, etc. The active substances in the positive gel sheet use materials such as carbon nanotubes, graphene, and conductive polymers with excellent electrical and thermal conductivity.

[0094] The combination of active substances with excellent electrical conductivity and a hydrogel with a network structure as a pathway greatly increases the load area of the positive electrode and accelerates the charge transfer rate, thus solving the problem of small discharge current density and obtaining a battery with high areal energy density and high volumetric energy density. Using a dry cross-linking form to bond the electrolyte gel and the positive gel sheet to form an all-gel button zinc-air battery not only endows the battery with excellent electrochemical performance, but also makes the battery more firm and safer.

[0095] The above content is only to illustrate the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any modifications made on the basis of the technical solution according to the technical idea proposed by the present invention fall within the protection scope of the claims of the present invention.

Claims

1. A preparation method of a fully-gel zinc-air button battery, characterized in that, It includes the following steps: S1: Add water to the acrylamide matrix and stir, then add a conductive active substance or a conductive polymer, a pore former, and a binder and stir evenly. Then add a crosslinking agent, an initiator, and a catalyst to obtain a mixed solution I. Inject the mixed solution I into mold I and then dry it to obtain a dehydrated positive gel sheet (4); S2: Add water to the acrylamide matrix and stir, then add a crosslinking agent, an initiator, and a catalyst to obtain a mixed solution II. Inject the mixed solution II into mold II and then dry it to obtain a gel thin sheet. Then soak the gel thin sheet in an alkaline zinc salt electrolyte solution to obtain a gel electrolyte thin sheet (3); S3: Drop a platinum-carbon catalyst onto the upper surface of the dehydrated positive gel sheet (4) and perform interfacial dry crosslinking with the gel electrolyte thin sheet (3) to obtain an all-gel button-type integrated thin sheet; S4: Stack and encapsulate a negative electrode case (1), a zinc negative electrode sheet (2), the all-gel button-type integrated thin sheet, and an air positive electrode case (5) from bottom to top in sequence to obtain an all-gel zinc-air button battery; In S2, the alkaline zinc salt electrolyte solution is a compound solution of potassium hydroxide and zinc acetate; the mass ratio of potassium hydroxide to zinc acetate is (7 - 8:1); the soaking time is 72h - 96h.

2. The preparation method according to claim 1, characterized in that, The crosslinking agent is N,N'-methylenebisacrylamide; the catalyst is tetramethylethylenediamine; the initiator is one of ammonium persulfate or potassium persulfate.

3. The preparation method according to claim 1, characterized in that, In S1, the conductive active substance is one of carbon nanotubes, conductive carbon, and graphene; the conductive polymer is one of polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene).

4. The preparation method according to claim 1, characterized in that, In S1, the pore former is one of polyethylene glycol-600 or polyethylene glycol-1000; the binder is one of carboxymethyl cellulose or sodium carboxymethyl cellulose.

5. The preparation method according to claim 1, characterized in that, In S1, the mass ratio of acrylamide to the conductive active substance or conductive polymer, water, pore former, binder, crosslinking agent, catalyst, and initiator in the dehydrated positive gel sheet (4) is 1:(0.02 - 0.03):(2.5 - 3):(0.12 - 0.15):(0.025 - 0.03):(0.00025 - 0.0003):(0.001 - 0.0015):(0.007 - 0.0073).

6. The preparation method according to claim 1, characterized in that, In S2, the mass ratio of acrylamide to water, crosslinking agent, catalyst, and initiator in the gel electrolyte thin sheet (3) is 1:(2.5 - 3):(0.00025 - 0.0003):(0.001 - 0.0015):(0.007 - 0.0073).

7. The preparation method according to claim 1, characterized in that, In S1, mold I is a circular thin sheet mold with a diameter of 10 - 12 mm; in S2, mold II is a circular thin sheet mold with a diameter of 12 - 14 mm; the diameter of mold II is greater than that of mold I.

8. The preparation method according to claim 1, characterized in that, In S3, the platinum-carbon catalyst is a compound solution composed of platinum-carbon, isopropanol, and Nafion solution; the dosage of the platinum-carbon is 1 - 1.5 mg / cm 2 , and the mass ratio of the isopropanol to the Nafion solution is (20 - 24):

1.

9. A fully-gel zinc-air button battery prepared by using the preparation method according to any one of claims 1 to 8.

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