Reinforced composite electrolyte membrane for fuel cell

Patent metadata

Field	Value
Publication number	US-9893374-B2
Application number	US-201514678688-A
Country	US
Kind code	B2
Filing date	Apr 3, 2015
Priority date	Mar 31, 2006
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

Disclosed is a composite electrolyte membrane comprising a microporous polymer substrate and a sulfonated polymer electrolyte. The composite electrolyte membrane comprises: a first polymer electrolyte layer formed of a first non-fluorinated or partially-fluorinated sulfonated polymer electrolyte; a non-fluorinated or partially-fluorinated microporous polymer substrate stacked on the first polymer electrolyte layer, wherein pores of the microporous polymer substrate are impregnated with a second non-fluorinated or partially-fluorinated sulfonated polymer electrolyte, and the first polymer electrolyte and the second polymer electrolyte are entangled with each other on an interface thereof; and a third polymer electrolyte layer formed on the microporous polymer substrate impregnated with the second polymer electrolyte by a third non-fluorinated or partially-fluorinated sulfonated polymer electrolyte, wherein the second polymer electrolyte and the third polymer electrolyte are entangled with each other on an interface thereof. A method for manufacturing the composite electrolyte membrane, and a membrane-electrode assembly (MEA) and a fuel cell comprising the composite electrolyte membrane are also disclosed.

First claim

The invention claimed is:

1. A membrane-electrode assembly comprising an anode, a cathode and a composite electrolyte membrane provided between the anode and the cathode,
wherein the composite electrolyte membrane including a microporous polymer substrate and a sulfonated polymer electrolyte, the composite electrolyte membrane comprising:
a first polymer electrolyte layer formed of a first non-fluorinated sulfonated polymer electrolyte;
a non-fluorinated microporous polymer substrate stacked on the first polymer electrolyte layer, wherein pores of the microporous polymer substrate are impregnated with a second non-fluorinated sulfonated polymer electrolyte, and the first polymer electrolyte and the second polymer electrolyte are entangled with each other on an interface thereof,
a third polymer electrolyte layer formed on the microporous polymer substrate impregnated with the second polymer electrolyte by a third non-fluorinated sulfonated polymer electrolyte, wherein the second polymer electrolyte and the third polymer electrolyte are entangled with each other on an interface thereof,
the first non-fluorinated sulfonated polymer electrolyte, the second non-fluorinated sulfonated polymer electrolyte, and the third non-fluorinated sulfonated polymer electrolyte are each independently selected from the group consisting of homopolymers, alternating copolymers, random copolymers, block copolymers, multiblock copolymers and graft copolymers, and
the first non-fluorinated sulfonated polymer electrolyte, the second non-fluorinated sulfonated polymer electrolyte, and the third non-fluorinated sulfonated polymer electrolyte independently comprises at least one sulfonated hydrocarbon-based polymer selected from the group consisting of sulfonated poly(arylene ether)s, sulfonated poly(amide)s, sulfonated polyphosphazene, sulfonated radiation-grafted FEP-g-polystyrene, sulfonated radiation-grafted ETFE-g-polystyrene, sulfonated radiation-grafted LDPE-g-polystyrene, sulfonated radiation-grafted PVDF-g-polystyrene,
wherein each of the first polymer electrolyte layer and the third polymer electrolyte layer independently has a thickness of 1μm-50 μm.

2. The membrane-electrode assembly according to claim 1 ,
wherein the composite electrolyte membrane is manufactured in accordance with a method comprising:
a first step of applying a solution of the first non-fluorinated sulfonated polymer electrolyte onto a base to form the first polymer electrolyte layer;
a second step of stacking the non-fluorinated microporous polymer substrate on the first polymer electrolyte layer and allowing a solution of the second non-fluorinated sulfonated polymer electrolyte to infiltrate into pores of the microporous polymer substrate; and
a third step of applying a solution of the third non-fluorinated sulfonated polymer electrolyte onto the microporous polymer substrate impregnated with the second polymer electrolyte to form the third polymer electrolyte layer.

3. The membrane-electrode assembly according to claim 1 , wherein the microporous polymer substrate is formed of at least one material selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, polyimide and polyamide.

4. The membrane-electrode assembly according to claim 1 , wherein the microporous polymer substrate has a thickness ranging from 3μm to 1,000 μm, a porosity ranging from 20% to 95%, and a pore size ranging from 0.05μm to 20μm.

5. The membrane-electrode assembly according to claim 1 , which has a thickness of 10 μm-100 μm.

6. The membrane-electrode assembly according to claim 1 , wherein the second polymer electrolyte layer is formed by using a surfactant, while the first polymer electrolyte layer and the third polymer electrolyte layer are formed by using no surfactant.

7. The membrane-electrode assembly according to claim 1 , wherein the microporous polymer substrate is impregnated with the second polymer electrolyte via a solution pouring process using a solution of the second polymer electrolyte.

8. A fuel cell comprising the membrane-electrode assembly composite electrolyte membrane as defined in claim 1 .

Assignees

• Lg Chemical Ltd

Inventors

• Kim Eun Ju
• Shin Chong Kyu
• Lee Bong Keun
• Choi Seong Ho

Classifications

• Y02P70/50

  Manufacturing or production processes characterised by the final manufactured product · CPC title

• H01M8/1032

  having sulfur, e.g. sulfonated-polyethersulfones [S-PES] · CPC title

• H01M2300/0088

  Composites · CPC title

• H01M2300/0082

  Organic polymers · CPC title

• H01M8/1053 Primary

  consisting of layers of polymers with at least one layer being ionically conductive · CPC title