CN115487688A - Water electrolysis cell composite diaphragm with ultra-smooth surface and preparation process thereof - Google Patents
Water electrolysis cell composite diaphragm with ultra-smooth surface and preparation process thereof Download PDFInfo
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- B01D67/0002—Organic membrane manufacture
- B01D67/0023—Organic membrane manufacture by inducing porosity into non porous precursor membranes
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- B01D69/12—Composite membranes; Ultra-thin membranes
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- C25B1/00—Electrolytic production of inorganic compounds or non-metals
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- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B13/00—Diaphragms; Spacing elements
- C25B13/02—Diaphragms; Spacing elements characterised by shape or form
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- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B13/00—Diaphragms; Spacing elements
- C25B13/04—Diaphragms; Spacing elements characterised by the material
- C25B13/08—Diaphragms; Spacing elements characterised by the material based on organic materials
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- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
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Abstract
The invention relates to a water electrolysis bath composite diaphragm with an ultra-smooth surface and a preparation process thereof. The preparation process comprises the following steps: 1) Perforating the polymer film to obtain a porous film with the pore size of 400-500 microns and the pore density of 30-50 pores per inch; 2) Impregnating the porous membrane with a membrane casting solution; 3) Applying pressure to the porous membrane; 4) Carrying out phase conversion on the porous membrane in a coagulating bath to obtain the composite diaphragm of the water electrolyzer; the pressure is below 5MPa, and the casting solution comprises a polymer, a pore-foaming agent, a hydrophilic agent and a solvent. The surface of the composite diaphragm of the water electrolyzer prepared by the preparation process is ultra-flat, the problem of warp and weft crossing point protrusion caused by the traditional mesh grid is solved, and the conductivity, tensile strength and alkali resistance of the diaphragm product can be improved.
Description
Technical Field
The invention belongs to the technical field of hydrogen production by electrolyzing water, and particularly relates to a water electrolysis bath composite diaphragm with an ultra-smooth surface and a preparation process thereof.
Background
At present, domestic water electrolysis hydrogen production equipment mainly uses an alkaline electrolysis bath, wherein a diaphragm occupies an important position and is positioned between an anode and a cathode, and the diaphragm is mainly used for preventing the mixing of oxygen on the anode side and hydrogen on the cathode side, so that the purity of the generated hydrogen and oxygen is improved, and the safety is ensured.
In the early days, asbestos cloth was used as a diaphragm in industry, but the asbestos cloth was eliminated due to the defects of poor temperature resistance, high pollution and the like. At present, the diaphragm is mainly made of polyphenylene sulfide woven cloth, but the diaphragm has the defects of poor hydrophilicity and poor air tightness, after long-time use, the pore diameter of the diaphragm is filled with air bubbles, so that the electric conductivity of the diaphragm is reduced, and the woven cloth is woven by warp yarns and weft yarns, wherein the crossed part of the warp yarns and the weft yarns is thicker than the non-crossed part, so that the surface of the woven cloth is not very flat, and the surface of the diaphragm prepared by taking the woven cloth as a base material also has the problem of bulge caused by the crossed part of the warp yarns and the weft yarns.
Chinese patent CN101372752a discloses that the hydrophilicity is improved by sulfonating polyphenylene sulfide by dipping it in sulfuric acid, but this method still has a problem that the surface of the resulting separator is not very flat.
Chinese patent CN 114432906A discloses a high temperature resistant alkaline water electrolyzer composite diaphragm prepared by using a polyphenylene sulfide mesh as a porous membrane, preparing polysulfone, polyvinylpyrrolidone, zirconium dioxide and metal salt into a membrane casting solution, soaking the porous membrane in the membrane casting solution, and scraping the membrane casting solution with a scraper after the porous membrane is fully soaked. Although the method improves the alkali resistance of the diaphragm to a certain extent, the woven mesh is still used as a base material, the surface of the prepared diaphragm has the problems of certain bulges and poor flatness, and the casting solution on the two sides of the porous membrane is partially separated, so that the composite diaphragm is difficult to form a firm whole.
Disclosure of Invention
The invention aims to provide a preparation process of a water electrolysis bath composite diaphragm with an ultra-smooth surface, the preparation process can be used for preparing the water electrolysis bath composite diaphragm with the ultra-smooth surface, and the process can be used for simultaneously improving the conductivity, the tensile strength and the alkali resistance of a product.
In order to achieve the purpose, the invention adopts the technical scheme that:
a preparation process of a composite diaphragm of a water electrolyzer comprises the following steps: 1) Perforating the polymer film to obtain a porous film with the pore size of 400-500 microns and the pore density of 30-50 pores per inch; 2) Impregnating the porous membrane with a membrane casting solution; 3) Applying pressure to the porous membrane; 4) Carrying out phase conversion on the porous membrane in a coagulating bath to obtain the composite diaphragm of the water electrolyzer; the pressure is below 5MPa, and the casting solution comprises a polymer, a pore-foaming agent, a hydrophilic agent and a solvent.
The porous membrane has proper porosity due to the adoption of the pore density, so that hydroxide ions can smoothly pass through the composite membrane during water electrolysis, and higher conductivity is ensured. The shape of the hole is not particularly limited, and may be, for example, a circle or a square.
Further, the material of the polymer film is selected from one or more of polytetrafluoroethylene, polypropylene, polyethylene naphthalate, polyetheretherketone, polyetherketoneketone, polyphenylene oxide, polysulfone, polyphenylene sulfide and polyimide. Preferably, the material of the polymer film is polytetrafluoroethylene.
Further, the thickness of the polymer film is 200-400 microns.
Further, the pressure is 0.5-5MPa. Preferably, the pressure is 0.5 to 3MPa.
Further, the applying pressure is performed at 20-60 ℃. Preferably, said applying pressure is performed at 25-40 ℃.
Further, the time for applying the pressure is 3-10min. Preferably, the time for applying the pressure is 5-8 min.
Further, a pressing roller is used for applying the pressure, the pressing roller is connected with an air compressor, and the pressure between the pressing rollers is adjusted by the air compressor.
In some embodiments, the polymer is selected from the group consisting of polyvinyl alcohol, polyetheretherketone, polyimide, polyethersulfone, polysulfone, polybenzimidazole, chitosan, polytetrafluoroethylene, polyetherimide, and polyvinyl chloride. The aforementioned polymers can undergo phase inversion in subsequent processes.
Preferably, the polymer is selected from one or more of polysulfone, polyethersulfone and polybenzimidazole in combination.
In some embodiments, the porogen is selected from the group consisting of one or more of cyclodextrin, polyethylene glycol, urea, polyvinylpyrrolidone, polyacrylamide, starch, sodium chloride, sucrose, and polyurethane.
Preferably, the porogen is selected from one or more of polyvinylpyrrolidone, cyclodextrin and urea in combination.
In some embodiments, the hydrophilic agent is selected from the group consisting of polyvinyl alcohol, cellulose, starch, titanium dioxide, silicon dioxide, and zirconium dioxide.
Preferably, the hydrophilic agent is selected from titanium dioxide and zirconium dioxide.
In the prior art, a woven net material is generally adopted as a base material of the diaphragm, the thickness of the crossed part of warp yarns and weft yarns of the woven net is increased, and the surface and the hand feeling of the diaphragm are not smooth enough due to the crossed part after the membrane casting solution is soaked and the phase inversion is completed. The inventor overcomes the technical bias in the field, and punches the polymer film to prepare the porous film, the porous film can realize the porous performance of the mesh grid material, and simultaneously the problem that the surface can see the protruding cross points due to the inconsistent thickness is avoided. The inventor also discovers through research that the solid content of the membrane casting solution on the porous membrane can be improved by applying pressure to the porous membrane after the membrane casting solution is soaked before phase inversion, and the applied pressure can enable the membrane casting solutions on two sides of the porous membrane to be completely attached to the porous membrane, so that the problem that holes are formed in the composite membrane due to incomplete attachment of the membrane casting solutions on two sides of the porous membrane due to the thickness of the porous membrane is avoided, and the holes in the composite membrane are main factors causing reduction of the conductivity of the composite membrane. And the surface of the finally prepared water electrolyzer composite diaphragm is free from wrinkles by applying pressure to the porous membrane.
Further, the mass ratio of the polymer to the pore-foaming agent to the hydrophilic agent is 10 to 20:3 to 15:0.5 to 6. Preferably, the mass ratio of the polymer to the pore-forming agent to the hydrophilic agent is 10 to 20:10 to 15:1~6.
Further, the solvent is selected from one or more of N-methyl pyrrolidone, N-dimethyl formamide and N, N-dimethyl acetamide.
Further, the solid content of the casting solution is 10 to 40 percent.
In some embodiments, the time of the impregnation is 10 to 60min and the temperature of the impregnation is 20 to 30 ℃.
In some embodiments, the method further comprises the step of coating the membrane-casting solution on the porous membrane impregnated with the membrane-casting solution using a coating roller before the applying pressure. The coating step can further ensure that the porous membrane is completely covered by the membrane casting solution, and the possibility that the part of the porous membrane is not covered by the membrane casting solution is reduced.
In some embodiments, the method of making comprises the steps of: 1) Punching the polymer film by a punching machine to obtain a porous film with the aperture size of 400-500 microns and the pore density of 30-50 pores per inch; 2) Dissolving the polymer in the solvent, adding the hydrophilic agent and the pore-forming agent, uniformly stirring, filtering, and defoaming in vacuum to obtain the membrane casting solution; 3) Dipping the porous membrane in the membrane casting solution, and coating the membrane casting solution on the porous membrane by using a coating roller; 4) Applying pressure to the porous film with a pressure roller; 5) And standing the porous membrane, and performing phase inversion on the porous membrane in a first coagulation bath and a second coagulation bath to obtain the composite diaphragm of the water electrolyzer.
In some embodiments, the stirring is performed at a speed of 200 to 800rpm for a period of 1 to 48 hours.
In some embodiments, the filtration is performed using a filter having a pore size of 1-10 μm, the number of filtrations being 2~5.
In some embodiments, the vacuum debubbling temperature is 20-100 deg.C, and the vacuum degree is 1 × 10 5 ~1×10 -5 Pa。
In some embodiments, the temperature of the resting is from 25 to 50 ℃ for from 25 to 60 seconds.
In some embodiments, the first and second coagulation baths are each selected from the group consisting of water, ethanol, methanol, acetone, dimethylformamide, and dimethylacetamide.
The invention also provides the composite diaphragm of the water electrolyzer, which is prepared by the preparation process.
Further, the resistance of the composite diaphragm of the water electrolyzer is 0.4 omega/cm 2 And the tensile strength is more than 22MPa, and the composite diaphragm of the water electrolyzer is soaked in a boiling KOH solution with the mass fraction of 30 percent for 5 h, and the alkali loss is less than 0.40 percent.
Preferably, the resistance of the composite diaphragm of the water electrolyzer is 0.3 omega/cm 2 The tensile strength is 26MPa or more.
Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages.
Through the porous membrane that punches the polymer film and obtain, for the woven mesh that the tradition used, the surface smoothness obviously improves, and the diaphragm that obtains of preparation also can not have bellied problem, and the surface of diaphragm and feeling all surpass levelly and smoothly.
Before phase inversion, pressure is applied to the porous membrane after the membrane casting solution is immersed, so that the finally prepared composite diaphragm of the water electrolysis cell has the advantages of improved conductivity, reduced resistance, improved tensile strength, alkali resistance and low alkali loss. The pressure is applied to the porous membrane, so that the surface of the finally prepared water electrolysis cell composite diaphragm is free from wrinkles.
Drawings
Fig. 1 is a photograph of a composite separator of example 1;
fig. 2 is a photograph of a composite separator of comparative example 1;
fig. 3 is a photograph of the composite separator of comparative example 2.
Detailed Description
The technical solutions of the present invention are described in detail below with reference to specific examples so that those skilled in the art can better understand and implement the technical solutions of the present invention, but the present invention is not limited to the scope of the examples.
The polytetrafluoroethylene membranes in the following examples and comparative examples were purchased from the national pharmacy group and had a molecular weight of 8 ten thousand, the polytetrafluoroethylene fiber filaments were purchased from the national pharmacy group and had a molecular weight of 8 ten thousand, the polysulfones were purchased from the national pharmacy group and had a molecular weight of 8 ten thousand, and the polyvinylpyrrolidone was purchased from the national pharmacy group and had a molecular weight of 4 ten thousand.
Example 1
The embodiment provides a composite diaphragm of a water electrolyzer, which is prepared by the following steps:
1) A polytetrafluoroethylene film having a thickness of 300 μm was taken, dried, and put into a punch, and round holes having a side length of 425 μm were punched at 40 holes/inch to obtain a porous film.
2) Dissolving polysulfone in N-methyl pyrrolidone, stirring, adding polyvinylpyrrolidone, stirring, adding zirconium dioxide, magnetically stirring at 500 rpm for 24h, filtering with 5 μm filter for 3 times, and vacuum degree of 1 × 10 -5 And (4) defoaming under the conditions of Pa and the temperature of 70 ℃ to obtain a casting solution. Wherein the polysulfone: polyvinylpyrrolidone: the weight ratio of zirconium dioxide is 10:10:3, the solid content of the casting solution is 30%.
3) And (3) placing the porous membrane in the membrane casting solution to be soaked for 30 min, taking out the porous membrane, and coating the membrane casting solution on the porous membrane again by using a coating roller.
4) The porous membrane was pressurized at 40 ℃ and 0.5MPa for 5 min by a pressure roller connected to a pneumatic press.
5) Then, the membrane was left to stand at 30 ℃ for 30 s, and then the porous membrane was subjected to a first coagulation bath and a second coagulation bath in a mixed solution of ethanol and acetone (the mass ratio of the two solutions was 7:3), to obtain a composite separator for a water electrolyzer.
Example 2
This example provides a composite diaphragm for a water electrolyser, the method of manufacture of which is substantially the same as example 1 except that: polysulfone in membrane casting solution: polyvinylpyrrolidone: the weight ratio of zirconium dioxide is 10:10:6.
example 3
This example provides a composite diaphragm for a water electrolyser, the method of manufacture of which is substantially the same as example 1 except that: step 1), the pore size is 500 microns, and the pore density is 30 pores per inch; and step 4) pressurizing the porous membrane at 60 ℃ and 3MPa by utilizing a pressurizing roller connected with an air compressor, wherein the pressurizing time is 5 min.
Example 4
This example provides a composite diaphragm for a water electrolyser, the method of manufacture of which is substantially the same as example 1 except that: step 1) the pore size is 400 microns and the pore density is 50 pores per inch; and 4) pressurizing the porous membrane at 20 ℃ and 2MPa by utilizing a pressurizing roller connected with a pneumatic press, wherein the pressurizing time is 5 min.
Example 5
This example provides a composite separator for a water electrolyzer, which is basically prepared in the same manner as in example 1 except that: and 4) pressurizing the porous membrane at 40 ℃ and 1MPa by utilizing a pressurizing roller connected with a pneumatic press, wherein the pressurizing time is 8 min.
Example 6
This example provides a composite diaphragm for a water electrolyser, the method of manufacture of which is substantially the same as example 1 except that: replacing zirconium dioxide with titanium dioxide, wherein polysulfone in the membrane casting solution: polyvinylpyrrolidone: the weight ratio of the titanium dioxide is 10:10:1.
example 7
This example provides a composite diaphragm for a water electrolyser, the method of manufacture of which is substantially the same as example 1 except that: replacing zirconium dioxide with titanium dioxide, and preparing polysulfone in the membrane casting solution: polyvinylpyrrolidone: the weight ratio of the titanium dioxide is 10:10:2.
example 8
This example provides a composite diaphragm for a water electrolyser, the method of manufacture of which is substantially the same as example 1 except that: replacing zirconium dioxide with titanium dioxide, and preparing polysulfone in the membrane casting solution: polyvinylpyrrolidone: the weight ratio of the titanium dioxide is 10:10:3.
comparative example 1
This comparative example also provides a composite separator for a water electrolyser, the method of manufacture of which is substantially the same as example 1, except that: step 4) is not performed.
Comparative example 2
The comparative example also provides a composite diaphragm of a water electrolyzer, and the preparation method comprises the following steps:
1) The polytetrafluoroethylene fiber filaments were woven into a web with a warp and weft density of 100 threads/inch.
2) Dissolving polysulfone in N-methyl pyrrolidone, stirring, adding polyvinylpyrrolidone, stirring, adding zirconium dioxide, magnetically stirring at 500 rpm for 24h, filtering with 5 μm filter for 3 times, and vacuum degree of 1 × 10 -5 And (4) defoaming at the temperature of 70 ℃ under Pa to obtain a casting solution. Wherein the polysulfone: polyvinylpyrrolidone: the weight ratio of zirconium dioxide is 10:10:3, the solid content of the casting solution is 30%.
3) And (3) placing the porous membrane in the membrane casting solution to be soaked for 30 min, taking out the porous membrane, and coating the membrane casting solution on the porous membrane again by using a coating roller.
4) Then, the membrane was left to stand at 30 ℃ for 30 s, and then the porous membrane was subjected to a first coagulation bath and a second coagulation bath in a mixed solution of ethanol and acetone (the mass ratio of the two solutions was 7:3), to obtain a composite separator for a water electrolyzer.
For the water electrolysis cell composite membranes prepared in the examples 1-8 and the comparative examples 1-2, the resistance of the water electrolysis cell composite membranes is tested by using an electrochemical working CHI650E station, and the specific operation is that the composite membranes are soaked in absolute ethyl alcohol for 2 hours, are fully wetted and then are soaked in 1mol/L KOH solution for 24 hours, and then are clamped in the middle of an electrolytic cell. The middle part of the electrolytic cell is two round plates with small holes, and the two semi-electrolytic cells clamp the middle diaphragm through special stainless steel clamps. Stainless steel metal plates are respectively inserted into the electrolytic cell to be used as auxiliary electrodes, and KOH solution of 1mol/L is injected into two sides of the diaphragm. The tensile strength was tested using the GB1040-79 standard, and it was immersed in a boiling 30% KOH solution at 5 h and its alkali loss was tested using the JC211-77 standard, the results of which are shown in Table 1 below.
In addition, the photograph of the composite separator for a water electrolyzer prepared in example 1 is shown in fig. 1, and it can be seen that the surface thereof is ultra-flat and smooth, no wrinkles are formed, and local cross-point protrusions are not seen, whereas the photograph of the composite separator for a water electrolyzer prepared in comparative example 1 is shown in fig. 2, and it can be seen that the surface thereof exhibits significant wrinkles, and a film formed by unsuccessfully distributing a casting solution on a local porous film, and the photograph of the composite separator for a water electrolyzer prepared in comparative example 2 is shown in fig. 3, and it can be seen that significant weaving cross-point protrusions are formed, and surface wrinkles are formed.
As can be seen from the results of the above examples and comparative examples, the present invention can avoid the protrusions caused by the weaving intersections of the conventional woven mesh substrate by perforating the polymer film to form the porous film and using it as the substrate of the separator; and before phase inversion, the porous membrane impregnated with the membrane casting solution is subjected to pressurization treatment, so that various performances of the final composite membrane can be improved.
The above embodiments are only for illustrating the technical idea and features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the content of the present invention and implement the present invention, and not to limit the protection scope of the present invention by this means. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.
Claims (12)
1. The preparation process of the composite diaphragm of the water electrolyzer is characterized by comprising the following steps: 1) Perforating the polymer film to obtain a porous film with the pore size of 400-500 microns and the pore density of 30-50 pores per inch; 2) Impregnating the porous membrane with a membrane casting solution; 3) Applying pressure to the porous membrane; 4) Carrying out phase conversion on the porous membrane in a coagulating bath to obtain the composite diaphragm of the water electrolyzer; the pressure is below 5MPa, and the casting solution comprises a polymer, a pore-foaming agent, a hydrophilic agent and a solvent.
2. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the material of the polymer film is selected from one or a combination of more of polytetrafluoroethylene, polypropylene, polyethylene naphthalate, polyether ether ketone, polyether ketone, polyphenyl ether, polysulfone, polyphenylene sulfide and polyimide; and/or the thickness of the polymer film is 200-400 microns.
3. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the pressure is 0.5-5MPa; and/or, the applying pressure is performed at 20-60 ℃; and/or the pressure is applied for 3-10min.
4. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the pressure is 0.5-3MPa; and/or, the applying pressure is performed at 25-40 ℃; and/or the pressure is applied for 5-8 min.
5. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the polymer is selected from one or more of polyvinyl alcohol, polyether ether ketone, polyimide, polyether sulfone, polysulfone, polybenzimidazole, chitosan, polytetrafluoroethylene, polyether imide and polyvinyl chloride; and/or the pore-foaming agent is selected from one or more of cyclodextrin, polyethylene glycol, urea, polyvinylpyrrolidone, polyacrylamide, starch, sodium chloride, sucrose and polyurethane; and/or the hydrophilic agent is selected from one or more of polyvinyl alcohol, cellulose, starch, titanium dioxide, silicon dioxide and zirconium dioxide.
6. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the polymer is selected from one or more of polysulfone, polyethersulfone and polybenzimidazole; and/or the pore-foaming agent is selected from one or more of polyvinylpyrrolidone, cyclodextrin and urea; and/or the hydrophilic agent is selected from titanium dioxide and zirconium dioxide.
7. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the mass ratio of the polymer to the pore-foaming agent to the hydrophilic agent is 10 to 20:3 to 15:0.5 to 6; and/or, the solvent is selected from one or more of N-methyl pyrrolidone, N-dimethyl formamide and N, N-dimethyl acetamide; and/or the solid content of the casting solution is 10-40%.
8. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the dipping time is 10-60min, and the dipping temperature is 20-30 ℃; and/or the preparation process further comprises the step of coating the porous membrane impregnated with the membrane casting solution by using a coating roller before applying the pressure.
9. The process for preparing a composite diaphragm of a water electrolyzer according to claim 1, characterized in that: the preparation process comprises the following steps: 1) Punching the polymer film by a punching machine to obtain a porous film with the aperture size of 400-500 microns and the pore density of 30-50 pores per inch; 2) Dissolving the polymer in the solvent, adding the hydrophilic agent and the pore-forming agent, uniformly stirring, filtering, and defoaming in vacuum to obtain the membrane casting solution; 3) Dipping the porous membrane in the membrane casting solution, and coating the membrane casting solution on the porous membrane by using a coating roller; 4) Applying pressure to the porous film with a pressure roller; 5) And standing the porous membrane, and performing phase inversion on the porous membrane in a first coagulation bath and a second coagulation bath to obtain the composite diaphragm of the water electrolyzer.
10. The process for preparing a composite diaphragm for a water electrolyzer of claim 9, characterized in that: the stirring speed is 200-800rpm, and the stirring time is 1-48h; and/or, the filtration is carried out by adopting a filter with the pore diameter of 1-10 μm, and the filtration frequency is 2~5 times; and/or, the temperature of the vacuum defoaming is 20-100 ℃, and the vacuum degree is 1 multiplied by 10 5 ~1×10 -5 Pa; and/or, the standing temperature is 25-50 ℃ and the standing time is 15-60s; and/or the first coagulation bath and the second coagulation bath are respectively selected from one or more of water, ethanol, methanol, acetone, dimethylformamide and dimethylacetamide.
11. A composite diaphragm of a water electrolyzer is characterized in that: the composite diaphragm of the water electrolyzer is prepared by the preparation process of the composite diaphragm of the water electrolyzer according to any one of claims 1 to 10.
12. The composite diaphragm for water electrolysers of claim 11 wherein: the resistance of the water electrolyzer composite diaphragm is 0.4 omega/cm 2 And the tensile strength is more than 22MPa, and the composite diaphragm of the water electrolyzer is soaked in a boiling KOH solution with the mass fraction of 30 percent for 5 h, and the alkali loss is less than 0.40 percent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211389876.0A CN115487688A (en) | 2022-11-08 | 2022-11-08 | Water electrolysis cell composite diaphragm with ultra-smooth surface and preparation process thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211389876.0A CN115487688A (en) | 2022-11-08 | 2022-11-08 | Water electrolysis cell composite diaphragm with ultra-smooth surface and preparation process thereof |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101552328A (en) * | 2009-05-18 | 2009-10-07 | 奇瑞汽车股份有限公司 | Compound diaphragm of multi-micropore battery and preparation method thereof |
| WO2015140356A2 (en) * | 2014-03-21 | 2015-09-24 | Vito Nv (Vlaamse Instelling Voor Technologisch Onderzoek Nv) | Film-supported polymeric membranes and methods of manufacturing |
| CN114457379A (en) * | 2022-01-24 | 2022-05-10 | 天津市大陆制氢设备有限公司 | Gel filling film for alkaline electrolytic cell and preparation method thereof |
| CN114927829A (en) * | 2021-02-01 | 2022-08-19 | 浙江大学 | Diaphragm of water-based battery and preparation method thereof |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101552328A (en) * | 2009-05-18 | 2009-10-07 | 奇瑞汽车股份有限公司 | Compound diaphragm of multi-micropore battery and preparation method thereof |
| WO2015140356A2 (en) * | 2014-03-21 | 2015-09-24 | Vito Nv (Vlaamse Instelling Voor Technologisch Onderzoek Nv) | Film-supported polymeric membranes and methods of manufacturing |
| CN114927829A (en) * | 2021-02-01 | 2022-08-19 | 浙江大学 | Diaphragm of water-based battery and preparation method thereof |
| CN114457379A (en) * | 2022-01-24 | 2022-05-10 | 天津市大陆制氢设备有限公司 | Gel filling film for alkaline electrolytic cell and preparation method thereof |
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