A proton exchange film for direct carbinol fuel battery and its making method

Abstract

The invention discloses a preparation method of a proton exchange membrane used for a direct methanol fuel cell. The method is realized by that polyether ether ketone is added into concentrated sulfuric acid to carry out sulfonation reaction, thereby obtaining sulfonated polyether ether ketone, then the sulfonated polyether ether ketone is dissolved in organic solvent, N, N (1)-Carbonyldiimidazole is added to stir for one to three hours, coupling agent is mixed for stirring the reaction for 1.5 to 4 hours, then inorganic crosslinking agent is mixed to react under the temperature of 50 to 80 DEG C. Proton conductors are mixed to continue getting the mixed solution of the sulfonated polyether ether ketone or the inorganic crosslinking agent or proton conductors under the temperature. Finally the proton exchange membrane for a direct methanol fuel cell is obtained by that the mixed solution of the sulfonated polyether ether ketone or the inorganic crosslinking agent or proton conductors is / are processed through membrane forming, drying and exuviation. The membrane has the advantages of good methanol diffusion resistance, low cost, high proton conductivity and good water-resistant swelling performance under high temperature. The preparation method is simple, the raw materials have low price, and the production cost is low.

Description

technical field [0001] The invention belongs to the technical field of fuel cells, in particular to a proton exchange membrane for direct methanol fuel cells and a preparation method thereof. Background technique [0002] Direct methanol fuel cell (DMFC) is a kind of fuel cell that uses methanol as fuel and oxygen or air as oxidant. DMFC not only has the advantages of rich fuel resources, low cost, and high energy density, but also the fuel methanol used in DMFC does not have the problems of difficult preparation, storage, transportation, and unsafety of fuel hydrogen used in hydrogen / oxygen or hydrogen / air fuel cells; When working, the fuel is directly fed, without additional reforming and humidification treatment; the structure of the battery stack system is simple, the response time is short, and the operation is convenient. Therefore, DMFC is considered to be a kind of fuel cell with great development potential and application value in the appl...

AI Technical Summary

Problems solved by technology

[0005] l. The SPEEK membrane with a higher sulfonation degree is not only easy to swell with water at a higher temperature, but the dimensional stability of the membrane is poor, and the membrane will become brittle, which will eventually reduce the mechanical strength of the membrane; while the SPEEK with a lower sulfonation degree is not easy Soluble in organic solvents, it is difficult to process into films, and the proton conductivity of the produced films is low, which cannot meet the requirements of DMFC for electrical properties;

[0006] 2. In the process of research on the modification of SPEEK membranes, the methods adopted so far are relatively simple: only introducing inorganic cross-linking structures into SPEEK can solve the swelling problem of the membrane and reduce the methanol permeability of the membrane, but it is also It leads to the decline of membrane proton conduction performance; and although only introducing heteropolyacid can improve membrane proton conduction performance, it will lead to the decline of membrane alcohol resistance performance, and heteropolyacid also faces the problem of seepage;

[0007] 3. The research on the preparation process and comprehensive performance of the composite SPEEK proton exchange membrane is not perfect enough. How to improve the dispersion degree of the additive particles in the SPEEK matrix and how to effectively adjust and control the composition ratio of the membrane material to make the proton conduction of the membrane There are still deficiencies in achieving the best balance between performance and alcohol resistance

[0008] 4. The proton conductivity of the proton exchange membranes developed so far for DMFC is still low, the permeability of methanol is still high, or the cost is relatively expensive, so it cannot meet the requirements of DMFC.

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