Composite polymer electrolyte membrane, membrane electrode assembly and solid polymer fuel cell using same

Patent metadata

Field	Value
Publication number	US-2020091532-A1
Application number	US-201716077861-A
Country	US
Kind code	A1
Filing date	Feb 13, 2017
Priority date	Feb 18, 2016
Publication date	Mar 19, 2020
Grant date	—

Abstract

A composite polymer electrolyte membrane has a high proton conductivity even under low-humidity, low-temperature conditions, a reduced dimensional change rate, a high mechanical strength and high chemical stability, and produces a solid polymer electrolyte fuel cell with a high output and high physical durability, a membrane electrode assembly, and a solid polymer electrolyte fuel cell containing the same. This composite polymer electrolyte membrane contains a composite layer composed mainly of a polyazole-containing nanofiber nonwoven fabric (A) and an ionic group-containing polymer electrolyte (B), the polyazole-containing nanofiber nonwoven fabric (A) being basic.

First claim

1 - 19 . (canceled)

20 . A composite polymer electrolyte membrane comprising a composite layer composed mainly of a polyazole-containing nanofiber nonwoven fabric (A) and an ionic group-containing polymer electrolyte (B), the polyazole-containing nanofiber nonwoven fabric (A) being basic.

21 . The composite polymer electrolyte membrane as set forth in claim 20 , wherein the polyazole-containing nanofiber nonwoven fabric (A) is a polybenzasole based nanofiber nonwoven fabric.

22 . The composite polymer electrolyte membrane as set forth in claim 20 , wherein the polyazole-containing nanofiber nonwoven fabric (A) is a nanofiber nonwoven fabric containing polybenzimidazole fibers.

23 . The composite polymer electrolyte membrane as set forth in claim 20 , wherein polyazole accounts for 80 wt % or more of the polyazole-containing nanofiber nonwoven fabric (A).

24 . The composite polymer electrolyte membrane as set forth in claim 20 , wherein the polyazole-containing nanofiber nonwoven fabric (A), examined by emission spectrum analysis, shows a ratio (I450/I300) of 0.30 or more and 1.4 or less wherein I450 and I300 are the peak intensities determined under excitation at 450 nm and 300 nm, respectively.

25 . The composite polymer electrolyte membrane as set forth claim 20 , wherein the polyazole-containing nanofiber nonwoven fabric (A) shows a weight change rate of 50% or less after staying in N-methyl-2-pyrolidone at 30° C. for 1 hour.

26 . The composite polymer electrolyte membrane as set forth in claim 20 , wherein the ionic group-containing polymer electrolyte (B) is an ionic group-containing aromatic hydrocarbon based polymer.

27 . The composite polymer electrolyte membrane as set forth in claim 20 , wherein the ionic group-containing polymer electrolyte (B) is a block copolymer comprising at least one ionic group-containing segment (B 1 ) and at least one ionic group-free segment (B 2 ).

28 . The composite polymer electrolyte membrane as set forth in claim 27 , wherein the ionic group-containing polymer electrolyte (B) forms a co-continuous type phase separated structure.

29 . A catalyst coated membrane comprising a catalyst layer formed on the composite polymer electrolyte membrane as set forth in claim 20 .

30 . A membrane electrode assembly comprising the composite polymer electrolyte membrane as set forth in claim 20 .

31 . A solid polymer electrolyte fuel cell comprising the composite polymer electrolyte membrane as set forth in claim 20 .

32 . An electrochemical hydrogen pump comprising the composite polymer electrolyte membrane as set forth in claim 20 .

33 . Water electrolysis hydrogen generation equipment comprising the composite polymer electrolyte membrane as set forth in claim 20 .

34 . A polyazole-containing nanofiber nonwoven fabric that, when examined by emission spectrum analysis, has a ratio (I450/I300) of 0.30 or more and 1.4 or less wherein I450 and I300 are the peak intensities determined under excitation at 450 mn and 300 nm, respectively.

35 . The polyazole-containing nanofiber nonwoven fabric as set forth in claim 34 having a polyazole content of 80 wt % or more and a weight change rate of 50% or less after contact with N-methyl-2-pyrolidone at 30° C. for 1 hour.

36 . A method of producing polyazole-containing nanofiber nonwoven fabric comprising:
step 1 dissolving polymers used as materials for a polyazole-containing nanofiber nonwoven fabric, step 2 producing a nanofiber nonwoven fabric precursor by electrospinning of the solution resulting from step 1, and step 3 performing insolubilization treatment of the nanofiber nonwoven fabric precursor resulting from step 2.

37 . The method as set forth in claim 36 , wherein the insolubilization treatment in step 3 comprises heat treatment at a temperature T(° C.) that meets equation (F1):
Tg 1−50(° C.)≤ T≤Tg 1+20(° C.)  (F1)

wherein Tg1 denotes the glass transition temperature (° C.) of the polyazole contained in the polyazole-containing nanofiber nonwoven fabric.

38 . The method as set forth in claim 36 , wherein the insolubilization treatment in step 3 comprises heat treatment performed after spreading a polyazole-containing nanofiber nonwoven fabric on a base having a glass transition temperature Tg2 (° C.) meeting equation (F2) and/or a melting point Tm (° C.):
Tg 2( Tm )> T   (F2)

wherein, Tg2 is the glass transition temperature (° C.) of the substance of the base and Tm(° C.) is the melting point of the substance of the base.

Assignees

• Toray Industries
• Japan Vilene Co Ltd

Inventors

• Okamoto Yumiko
• Izuhara Daisuke
• Yamaguchi Junpei
• Shirai Shusuke
• Kunita Tomoyuki
• Umeda Hiroaki
• WAKAMOTO Yuuta
• Ito Tatsunori
• MICHIHATA Noriko
• Tarao Takashi

Classifications

• D04H1/728

  by electro-spinning {(electro-spinning methods and apparatus D01D5/0007)} · CPC title

• D04H1/4326

  Condensation or reaction polymers · CPC title

• H01M8/1086

  After-treatment of the membrane other than by polymerisation · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/1004 Primary

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title