WO2016124052A1 - Proton exchange membrane for fuel cells and preparation method therefor - Google Patents

Abstract

A proton exchange membrane for fuel cells and a preparation method. In the present invention, a heteropoly acid is modified and then added to a proton conductive substrate resin, thereby inheriting the proton conductivity of the heteropoly acid and preventing the heteropoly acid from being washed away with water. The present proton exchange membrane has the advantages of high proton conductivity and long service life. Additionally, the method can be scaled for industrialized production with stable quality, and is suited for wide application in fuel cells.

Description

 Description: A fuel cell proton exchange membrane and a preparation method thereof

 [0001] The present invention relates to the field of fuel cell proton exchange membranes, and in particular to a fuel cell proton exchange membrane and a method of preparing the same.

 Background technique

 [0002] Proton exchange membrane is one of the key components in proton exchange membrane fuel cells (PEMFC). It is a dense proton-selective membrane that acts as a separator to separate fuel and oxidant from direct reaction. It also plays a role in conducting protons to electronic insulation. The performance of proton exchange membranes directly affects the performance of fuel cells, and is one of the key issues that restrict the large-scale commercial operation of fuel cells. With the in-depth study and development of proton exchange membranes, in order to improve the proton conductivity of proton exchange membranes, many methods have been proposed, such as: modification of proton conductive matrix resin to improve proton conductivity, and efficient addition. Proton conductivity materials, the development of new proton conductive materials, etc., have also made significant progress, but there are also many unresolved defects that limit their large-scale commercial operations and production.

 [0003] Adding a material having high proton conductivity to a matrix resin is one of the main means for solving the low proton conductivity of a proton exchange membrane, and the method can greatly improve the proton conductivity of a proton exchange membrane, and has broad application prospects and practicality. value. The high proton conductivity materials currently added to the proton exchange membrane are mostly solid heteropolyacids, which have high proton conductivity and compatibility, and can be added to the matrix resin to greatly enhance the proton exchange membrane protons. Excellent conductivity and performance, but due to the water-soluble nature of heteropoly acid, it is easily lost in the fuel cell during use, which causes the proton exchange membrane to proton conductivity with the fuel cell. The rapid decline in use has seriously affected the service life of fuel cells, resulting in limited use of fuel cells.

[0004] Chinese Patent Publication No. CN1848504A discloses a composite proton exchange membrane for a high temperature proton exchange membrane fuel cell and a preparation method thereof, which comprises a mixture of heteropoly acid and zirconium hydrogen phosphate with polybenzimidazole (PBI) or sulfonate. The polyaryloxyphosphazene was doped to prepare a composite proton exchange membrane material, and then formed into a film by a casting method. The proton exchange membrane prepared by the method has wide application temperature and good alcohol resistance, but The proton exchange membrane is obtained by physically mixing the heteropoly acid and zirconium hydrogen phosphate directly with polybenzimidazole (PBI) or sulfonated polyaryloxyphosphazene, and the heteropoly acid is easily lost with water in the fuel cell. However, the proton conductivity of the proton exchange membrane is rapidly reduced, which seriously affects the discharge performance and service life of the fuel cell.

[0005] Chinese Patent Publication No. CN101034747A discloses a method for preparing an inorganic proton exchange membrane fuel cell membrane, which first physically mixes a heteropoly acid with an inorganic oxide to prepare a precursor solution, and then with an inorganic proton conductive powder, thermoplastic The resin binder is hot pressed to prepare an inorganic proton exchange membrane. The membrane electrode prepared by the method has a high working temperature, but the proton exchange membrane is prepared by directly mixing the heteropoly acid, and the heteropoly acid is easily associated with water in the fuel cell. Loss and loss, the proton exchange membrane proton conductivity is rapidly reduced.

 [0006] Chinese Patent Publication No. CN102376961A discloses a high-performance polymer high-temperature proton exchange membrane for a high-temperature proton exchange membrane fuel cell and a preparation method thereof. The method treats the prepared homogeneous blend membrane with acidification (phosphoric acid or/and heteropolyacid) to have good high-temperature proton conductivity. The exchange membrane has excellent chemical stability, thermal stability, mechanical properties and high-temperature proton conductivity, but the heteropoly acid in the same proton exchange membrane is easily lost with the loss of water in the fuel cell, proton exchange of proton exchange membrane Fast decrease in performance, short service life and low discharge efficiency.

 [0007] According to the above, most of the existing heteropolyacid-doped proton exchange membranes are easily lost with the loss of water in the fuel cell, resulting in a rapid decrease in proton conductivity of the proton exchange membrane, and a service life. Short defects, therefore, the development of a proton exchange membrane in which the heteropoly acid is not lost and has good stability, proton conductivity and long life proton exchange membrane have important and commercial value for the promotion and application of fuel cells. Summary of invention

 technical problem

 [0008] At present, most of the proton exchange membranes doped with heteropolyacids are easily lost due to the loss of water in the fuel cell, resulting in a rapid decrease in the proton conductivity of the proton exchange membrane and a short service life.

 Problem solution

 Technical solution

[0009] The present invention provides a proton exchange membrane for a lignin fuel cell. Compared with other fuel cell proton exchange membranes, the present invention incorporates a modifier for modifying heteropolyacids and then adding them to proton conduction. In the matrix resin, the proton exchange conductivity of the heteropoly acid is maintained, and the proton exchange membrane is prevented from being lost together with water. The proton exchange membrane has the advantages of high proton conductivity and long service life. [0010] A further object of the present invention is to provide a method for preparing a proton exchange membrane for a fuel cell, which firstly modifies a heteropoly acid, and then dopes the heteropoly acid modified by the modification into a matrix resin. The proton exchange membrane is obtained by the membrane forming process, and the obtained proton exchange membrane has the advantages of good proton conductivity and long service life, satisfies the application of the proton exchange membrane on the fuel cell, and can be mass-produced industrially, with stable quality and suitable for fuel. Promotion and application of battery pairs.

 [0011] A fuel cell proton exchange membrane of the present invention is characterized by comprising a modified compound formed by an active group in a modifier and a metal ion of an amphoteric acid in a heteropoly acid under the action of hydrogen bonding and ionic bonding, The composition of the raw materials is as follows:

 [0012] 35-55 parts of the matrix resin,

 [0013] 25-40 parts of heteropoly acid,

 [0014] 10-25 parts of modifier,

 [0015] reinforcing fiber 5- 15 parts,

[0016] wherein the matrix resin is one or more of a sulfonated polyethersulfone, a sulfonated polyetheretherketone, a sulfonated polybenzimidazole, a sulfonated polysulfone, and a polyimide; The heteropoly acid is one of H ₅ GaW ₁₂ 0 ₄₀ , H ₂ PtW _u 0 ₃₆ , H 7As ₂ W ₁₈ 0 ₆₂ , H ₅ IW ₆ 0 ₂₄ , H ₈ CeMo _u 0 ₃₉ , H ₆ TeMo ₆ 0 ₂₄ Or a plurality of; the modifier is one or more of polyacrylamide, lauryl polyoxyethylene ether, diglycerin polypropylene glycol, N-methyl fatty acid amide, benzethonamide; The fiber is one or more of barium sulfate fiber, fluorocarbon polymer fiber, and silicon carbide fiber.

[0017] A method for preparing a proton exchange membrane for a fuel cell, the specific preparation steps are as follows:

[0018] 1) The part by weight of the heteropolyacid of 25-40 is completely dissolved with an appropriate amount of distilled water to form a solution, and 10 to 25 parts by weight of a modifier is added in a weight of 80-95 ° C, and the rotation speed is 150 _200 r / The reaction speed of min and the irradiation of ultraviolet light are 0. 5-lh, pressure filtration, and vacuum drying to obtain heteropoly acid modified compound A

[0019] 2) After completely dissolving the matrix resin in a weight fraction of 35-55 with an appropriate amount of the organic solvent, the heteropoly acid-modified compound A obtained in the step 1) and the reinforcing fiber in the weight fraction of 5-15 are added, and the mixture is uniformly stirred. After obtaining a casting solution;

The proton exchange membrane having a thickness of 0. 5-2 mm is obtained by a method of casting a film. [0021] In the above method for producing a fuel cell proton exchange membrane, wherein the organic solvent is one or more of dimethylamide, ethylenediamine, and isopropanol.

[0022] Heteropoly acid is a condensed oxo acid obtained by condensation of different oxoacids, is a protonic acid of uniform strength, has redox capability, has good proton conductivity, and is doped in proton conductive materials. The preparation of a proton exchange membrane can greatly improve the proton conductivity of the proton exchange membrane. The invention modifies the heteropoly acid, and uses the high-energy radiation of ultraviolet light, and the active group in the modifier and the metal ion of the amphoteric acid in the heteropoly acid form a new modification under the action of hydrogen bond and ionic bond. a compound having a property of a heteropolyacid and a modifier, a heteropolyacid moiety having hydrophilicity, capable of conducting protons, a modifier portion having water repellency, being insoluble in water, and preventing dissolution and loss of heteropoly acid, thereby It ensures that the conductivity of the proton exchange membrane will not decrease during the use of the fuel cell, and the service life and performance of the fuel cell are greatly improved, and the method is simple and convenient, low in cost, large-scale industrial production, stable in quality, suitable for fuel cells. Promotional application.

 Table 1: Comparison of performance between the present invention and a proton exchange membrane of a conventional doped heteropoly acid fuel cell

 [] [Table 1]

 Advantageous effects of the invention

 Beneficial effect

 [0024] The outstanding features and benefits of the present invention are:

 [0025] 1. The proton exchange membrane of the present invention contains a modified compound formed by a living group of a modifier and a metal ion of an amphoteric acid in a heteropoly acid under the action of a hydrogen bond and an ionic bond.

[0026] 2. The present invention solves the problem that most of the proton exchange membranes doped with heteropolyacids are easily lost with the loss of water in the fuel cell, resulting in a rapid decrease in the proton conductivity of the proton exchange membrane. Short-lived defects.

[0027] 3. The proton exchange membrane prepared by the invention has excellent proton conductivity and long service life, and can Large-scale industrial production, stable quality, suitable for the promotion and application of fuel cells.

 BEST MODE FOR CARRYING OUT THE INVENTION

 BEST MODE FOR CARRYING OUT THE INVENTION

 Embodiment 1

[0029] 1) The weight fraction of 25 H ₅ GaW ₁₂ 0 _4Q is completely dissolved with an appropriate amount of distilled water to form a solution, and 10 parts by weight of polyacrylamide is added in a weight ratio of 80 ° C and a rotation speed of 150 r / min. 5h, pressure filtration, and vacuum drying to obtain a heteropoly acid modified compound A;

 [0030] 2) After completely dissolving 55 parts by weight of the sulfonated polyethersulfone with an appropriate amount of dimethylamide, the heteropoly acid modified compound A obtained in the step 1) and the barium sulfate fiber in the weight part 15 are stirred. After mixing uniformly, a casting solution is obtained;

 The proton exchange membrane having a thickness of 0.5 mm is formed by a method of casting into a film.

 Invention embodiment

 Embodiments of the invention

 Example 2

[0033] 1) The weight fraction of 40 H ₂ PtW _u 0 ₃₆ is completely dissolved with an appropriate amount of distilled water to form a solution, and 25 parts by weight of lauryl polyoxyethylene ether is added in a weight of 95 ° C at a rotation speed of 200r / min stirring speed and ultraviolet light irradiation conditions for 1h, pressure filtration, and vacuum drying to obtain heteropoly acid modified compound A;

 [0034] 2) After completely dissolving the sulfonated polyetheretherketone in a weight of 35 with an appropriate amount of ethylenediamine, the heteropoly acid-modified compound A obtained in the step 1) and the fluorocarbon polymer fiber in the weight fraction of 5 are added. , stirring and mixing to obtain a casting solution;

 The proton exchange membrane having a thickness of 0.5 mm is formed by a method of casting into a film.

Embodiment 3

[0037] 1) The weight fraction of H ₇ As ₂ W ₁₈ 0 ₆₂ is completely dissolved in an appropriate amount of distilled water to form a solution, and 15 parts by weight of diglycerin polypropylene glycol is added in a weight of 85 ° C at a rotation speed of The reaction was carried out at a stirring speed of 180 r/min and under ultraviolet light irradiation for 0.5 h, pressure filtration, and vacuum drying to obtain a heteropoly acid modified compound A. [0038] 2) After completely dissolving the sulfonated polybenzimidazole in an amount of 45 with an appropriate amount of isopropyl alcohol, the heteropoly acid-modified compound A obtained in the step 1) and the silicon carbide fiber in the weight fraction of 9 are added and stirred. After mixing uniformly, a casting solution is obtained;

 [0039] 3) The casting solution obtained in the step 2) is cast into a film to form a proton exchange membrane having a thickness of 1 mm.

 Embodiment 4

[0041] 1) The weight fraction of H ₅ IW ₆ 0 ₂₄ is completely dissolved with an appropriate amount of distilled water to form a solution, and 20 parts by weight of N-methyl fatty acid amide is added in a weight ratio of 80 ° C at a rotation speed of The reaction speed of 160r / min and ultraviolet light irradiation conditions lh, pressure filtration, and vacuum drying to obtain heteropoly acid modified compound A;

 2) After completely dissolving 40 parts by weight of the sulfonated polysulfone with an appropriate amount of isopropanol, the heteropoly acid-modified compound A obtained in the step 1) and the barium sulfate fiber in the weight part 10 are added and stirred uniformly. After obtaining a casting solution;

[0043] 3) The casting solution obtained in the step 2) was cast into a film to form a proton exchange film having a thickness of 1.5 mm.

 Embodiment 5

[0045] 1) The weight fraction of 36 H ₂ PtW _u 0 ₃₆ was completely dissolved with an appropriate amount of distilled water to form a solution, and 23 parts by weight of lauryl polyoxyethylene ether was added in a weight of 85 ° C at a rotation speed of 190r / min stirring speed and ultraviolet light irradiation conditions for 1h, pressure filtration, and vacuum drying to obtain heteropoly acid modified compound A;

 [0046] 2) After completely dissolving the sulfonated polyetheretherketone of 38 parts with an appropriate amount of ethylenediamine, the heteropoly acid-modified compound A obtained in the step 1) and the silicon carbide fiber in the weight part of 5 are added and stirred. After mixing, the casting solution is obtained.

The proton exchange membrane having a thickness of 0.5 mm is formed by a method of casting into a film.

 Industrial applicability

 [0048] The present invention modifies the heteropoly acid and then adds it to the proton conductive matrix resin to maintain the proton conductivity of the heteropoly acid and prevent it from being lost together with water. The proton exchange membrane has protons. The utility model has the advantages of high electrical conductivity and long service life, and the method can be industrially produced on a large scale, and the quality is stable, and is suitable for the promotion and application of the fuel cell pair.

Claims

Claim  [Claim 1] A fuel cell proton exchange membrane characterized by containing a modified compound formed by an active group in a modifier and a metal ion of an amphoteric acid in a heteropoly acid under the action of hydrogen bonding and ionic bonding, Its weight composition is as follows:  35-55 parts of matrix resin, 25-40 parts of heteropoly acid,  Modifier 10-25 parts,  5-15 parts of reinforcing fiber,  The matrix resin is sulfonated polyethersulfone, sulfonated polyetheretherketone, sulfonated polybenzimidazole One or more of a sulfonated polysulfone and a polyimide; the heteropoly acid is H ₅ GaW ₁₂ 0 ₄₀ , H ₂ PtW _u 0 ₃₆ , H ₇ As ₂ W ₁₈ 0 ₆₂ , H ₅ IW ₆ 0 ₂₄ , H ₈ CeMo _u 0 ₃₉ , H ₆ One or more of TeMo ₆ 0 ₂₄ ; the modifier is one of polyacrylamide, lauryl polyoxyethylene ether, diglycerin polypropylene glycol, N-methyl fatty acid amide, benzethonamide Or a plurality of; the reinforcing fibers are one or more of barium sulfate fibers, fluorocarbon polymer fibers, and silicon carbide fibers.  [Claim] A method for preparing a fuel cell proton exchange membrane, the specific preparation steps are as follows:  1) The heteropolyacid of 25-40 parts by weight is completely dissolved with an appropriate amount of distilled water to form a solution, and 10-25 parts by weight of a modifier is added in a weight ratio of 80-95 ° C and a rotation speed of 150-20 Or/ 0_lh, pressure filtration, and vacuum drying to obtain heteropoly acid modified compound A; ag stirring speed and ultraviolet light irradiation conditions 0. 5_lh, pressure filtration, and vacuum drying to obtain a heteropoly acid modified compound A;  2) After completely dissolving the matrix resin in a weight of 35-55 with an appropriate amount of the organic solvent, the heteropoly acid-modified compound A obtained in the step 1) and the reinforcing fiber in the weight fraction of 5-15 are added, and the mixture is uniformly stirred to obtain a cast. Membrane solution  The proton exchange membrane having a thickness of 0.5-2 mm is formed by a method of casting into a film. [Claim 3] A method of producing a fuel cell proton exchange membrane according to claim 2, wherein the solvent is one or more of dimethylamide, ethylenediamine, and isopropanol. Summary  A fuel cell proton exchange membrane and a preparation method thereof. The present invention modifies the heteropoly acid and then adds it to the proton conductive matrix resin to maintain the proton conductivity of the heteropoly acid and prevent it from being lost together with water. The proton exchange membrane has high proton conductivity. The utility model has the advantages of long service life, and the method can be mass-produced industrially, and the quality is stable, and is suitable for the promotion and application of the fuel cell pair.