The invention relates to copolymers comprising: at least one recurrent unit of the following formula (I): ##STR00001## at least one recurrent unit of the following formula (II): ##STR00002## and at least one recurrent unit of the following formula (III): ##STR00003## wherein: R.sup.1 and R.sup.2 represent, independently of each other, an alkylene group; Z.sup.1 is a group of formula PO.sub.3R.sub.3R.sub.4, R.sub.3 and R.sub.4 representing, independently of each other, a hydrogen atom, an alkyl group or a cation; Z.sup.2 is a group of formula SO.sub.2R.sub.5, R.sub.5 representing an alkyl group or an aryl group; X and Y represent, independently of each other, a halogen atom or a perfluorocarbon group.

The invention relates to copolymers comprising: at least one recurrent unit of the following formula (I): ##STR00001## at least one recurrent unit of the following formula (II): ##STR00002## and at least one recurrent unit of the following formula (III): ##STR00003## wherein: R.sup.1 and R.sup.2 represent, independently of each other, an alkylene group; Z.sup.1 is a group of formula PO.sub.3R.sub.3R.sub.4, R.sub.3 and R.sub.4 representing, independently of each other, a hydrogen atom, an alkyl group or a cation; Z.sup.2 is a group of formula SO.sub.2R.sub.5, R.sub.5 representing an alkyl group or an aryl group; X and Y represent, independently of each other, a halogen atom or a perfluorocarbon group.

A laminated electrolyte membrane of an embodiment includes: a hydrocarbon-based electrolyte membrane; and a composite electrolyte membrane laminated with the hydrocarbon-based electrolyte, the composite electrolyte membrane containing a perfluorosulfonic acid-based electrolyte and a superstrong acid metal oxide having an acid function (H0) of 12 or less.

Disclosed is an electrolyte membrane for a membrane-electrode assembly including a block copolymer composed of a hydrophilic domain and a hydrophobic domain.

Disclosed is an electrolyte membrane for a membrane-electrode assembly including a block copolymer composed of a hydrophilic domain and a hydrophobic domain.

A compound containing at least one species of formula (I):

##STR00001## where: A.sup.x is an anion of valency x equal to 1 or 2 chosen from sulfonate, sulfonylimide of SO.sub.2N.sup.SO.sub.2C.sub.yF.sub.2y+1 type with y being an integer between 0 and 4; borate, borane, phosphate, phosphinate, phosphonate, silicate, carbonate, sulfide, selenate, nitrate and perchlorate anions; C.sup.x+ is a counter-cation of the anion A.sup.x, chosen from a proton H.sup.+ and alkali metal and alkaline-earth metal cations; p is an integer ranging from 1 to 10; E is an organic spacer comprising a linear sequence of at least two covalent bonds; n is an integer greater than or equal to 2; and G represents: (a) a group

##STR00002## or (b) a group

##STR00003## the anion A.sup.x being covalently bonded to the polycyclic group Ar.

Provided is a fuel cell electrode catalyst layer which includes a catalyst carrier having a large specific surface area and a polymer electrolyte having a form in which at least a portion thereof is agglomerated, the fuel cell electrode catalyst layer exhibiting excellent power generation performance in a high-humidity environment (for example, 100% RH).

The present specification relates to a block polymer and a polymer electrolyte membrane comprising the same, a membrane-electrode assembly comprising the polymer electrolyte membrane, a fuel cell comprising the membrane-electrode assembly, and a redox flow battery comprising the polymer electrolyte membrane.

A compound including a cation of the following structure is provided (1), wherein Q is selected from the group consisting of polymer residues and substituted or unsubstituted alkyl groups, and R is H or a polymer residue. A membrane including the above cation, and electrochemical devices employing this membrane, are also provided. ##STR00001##

A compound including a cation of the following structure is provided (1), wherein Q is selected from the group consisting of polymer residues and substituted or unsubstituted alkyl groups, and R is H or a polymer residue. A membrane including the above cation, and electrochemical devices employing this membrane, are also provided. ##STR00001##