摘要:
Disclosed herein is a method of making a component of a membrane electrode assembly. The method includes forming an electrode on an air-permeable backer comprising ePTFE, depositing a mixture comprising ionomer and a water-insoluble alcohol onto said electrode, drying said mixture to form a protective ionomer layer, and depositing an ePTFE-reinforced ionomer layer onto said protective ionomer layer.
摘要:
It is the objective of the present invention to provide a membrane with high ion selectivity, high physicochemical stability and low cost is of vital importance. This objective is achieved according to the present invention by an ion exchange membrane with selective ion transport properties, in particular for use in a redox flow battery, comprising: a) a mechanically robust and chemically resistant base polymer film (matrix); b) ion exchange groups covalently bound to the polymer matrix, being anion exchange groups or cation exchange groups or a mixture thereof; c) blocking groups covalently bound to the polymer matrix preventing the passage of redox-active species across the membrane;and d) optionally additional functional constituents, such as crosslinkers or antioxidants; Therefore, this membrane has a highion selectivity, high physicochemical stability and low cost due to the selection of a base polymer film and the ion exchange groups as well as the blocking groups preventing the passage of redox-active species across the membrane. Preferably, the membrane is produced via radiation induced grafting, comprising the steps of: a) exposing the base polymer to ionizing radiation to introduce active sites; b) exposing the irradiated base polymer to a mixture of monomers comprising i) a monomer containing an ion exchange group or a precursor monomer yielding an ion exchange group in a subsequent step, ii) a monomer containing a functional group to block the passage of redox-active species through the membrane or a precursor monomer yielding the functional blocking group in a subsequent reaction step; iii) optional additional monomers, such as a crosslinker and antioxidant;and c) in case of the use of precursor monomers for ion exchange sites and blocking groups, post-treatment of the grafted film to introduce ion exchange sites and/or blocking groups is performed.
摘要:
본 발명은 폴리아크릴로니트릴(polyacrylonitrile; PAN) 공중합체 용액을 전기 방사하여 형성한 부직포를 산화시켜 제조한 지지체 및 이에 함침시킨 탄화수소계 고분자 전해질을 포함하는 복합 전해질막; 폴리아크릴로니트릴 공중합체 용액을 전기 방사하여 형성한 부직포를 산화시켜 측쇄의 니트릴기의 질소원자와 이웃한 니트릴기의 탄소원자 간에 결합이 형성되면서 6각 고리를 형성함으로써 내용제성 또는 강도가 향상된 신규 지지체; 상기 복합 전해질막을 전해질막으로 구비한 막-전극 접합체(membrane-electrode assembly; MEA); 및 상기 막-전극 접합체를 구비한 연료전지에 관한 것이다. 본 발명에 따른 다공성 지지체 상에 전해질 고분자가 함침된 복합막은 높은 기공도를 유지하면서도 우수한 기계적 물성, 치수안정성, 내구성을 발휘한다.
摘要:
Disclosed are a reinforced composite membrane for fuel cells including a porous support comprising three-dimensionally irregularly and discontinuously arranged nanofibers of a polymer and a first ionic conductor, and a second ionic conductor filling pores of the porous support, wherein the first ionic conductor is present as nanofibers in the porous support or is present in the nanofibers of the polymer to form the nanofibers together with the polymer, and a membrane-electrode assembly for fuel cells including the same. As a result, impregnation uniformity and impregnation rate of the ionic conductors are improved and proton (hydrogen ion) conductivity is thus enhanced.
摘要:
The present invention is a hydrophilic polymer, which can be hydrated to form a hydrated hydrophilic polymer having a water content of at least 65%, wherein water content is defined as [(mass of the hydrated hydrophilic polymer- mass of the dry hydrophilic polymer)/mass of the hydrated hydrophilic polymer] x 100. The hydrophilic polymer may be hydrated to form a hydrated hydrophilic polymer having a water content of at least 65%. The present invention also 10 provides MEAs and electrochemical cells and methods of forming same.