Graft polymeric and ion-exchange membranes

Graft polymeric and ion-exchange membranes

the effect of operating parameters (temperature gradient, current density, flow bed design, fuel KK and oxidant pressure flow rates and losses...

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the effect of operating parameters (temperature gradient, current density, flow bed design, fuel

KK

and

oxidant

pressure

flow

rates

and

losses at the anode

pressure)

on the

have

side of

La,,,,Sr,,,8Mn0,1YSZ,

is applied

bed design,

on a plate

based

role

of the

fuel

flow

presenting

to an existing

design

the pressure

drop

sections

studies.

Chemical

Engineering

229-245

(June

using

for

Pauw)

and AC

the flow

results

from

W.M.

1.

Taama:

73(3)

of the cathodes

by

contributions

Scott,

compared

and properties SEM,

superior K.

and

than

with

which

XRD,

DC

have been studied

four-point

impedance these

systems

conductivity

Solid

State

K.-L. Zonks

Choy,

121(1-4)

Flame-assisted

B.C.H.

Steele:

107-113

(June

been

developed

deposition

as a simple

method

in manufacturing

(SOFC)

components

within

a single

and

in an open operation.

has

Stability of ceria-gadolinia electrolytes

cell

Doped

cost-effective oxide

An

fuel

in

electrolyte

planar

systems

electrolytes

appropriate

temperature

SOFCs.

with

ceria-based

atmosphere

because

interlayer between the cathode/electrolyte system has been demonstrated to improve conductivities

the

Cathode/

different

for

use

study,

high

impedance

environments

(Hz-N,

Patents

Graft polymeric membranes

oration, USA Ion-conducting constructed structures

Research

solid from

Nanocrystalline

electrolytes

nanoscale powders

and sintered

of dens&cation.

Applicant:

solid electrolytes

Nanomaterials

Corpare

precursor are pressed

material

here

Graft

polymeric

more

trifluorovinyl

degree with

base film

grafting

reaction

monomer

unit

The electrical

of an AglYSZIAg

cell

exchange

membranes

of

magnitude

enhancement

conductivity.

in

As an oxygen-sensing

standard O,IAglYSZIAgIN, nanocrystalline YSZ

element

Patent

element

in a

Publication

significant

oxygen

conductivity

at low temperatures.

The

to prepare

nanostructured

conducting

ion invention ion-

Inventors:

membranes.

polymeric

Publication Inventors:

US 5905000

date: 18 May T. Yadav,

H. Hu

from

as

them.

substituted

groups. there

specimens

The

the

oxidation

during to

the

on subsequent

cation

in

H,

membrane/electrode

pores.

Finely

carbon

particles

active

of

is porous,

composite

a catalytically

and 0,

part

pores, and the metal the

conductive

electrolysers. Patent number:

metal

Solid

1999).

from The

with

no closed

(June

of water

exchanger.

covered

present

J. Drennan:

253-262

the but

can also divided in the

may be loaded

metal

reactions

which

catalyses

in fuel

cells and

US 5906716

Inventors:

I?

ion-

Wagener,

1999

Mertesdorf,

A.

Schneller,

R.

H. Witteler

as membrane

Finned oxidant-cooled

1999

Applicant:

M-C

Power

stack

Corporation,

USA

Here a fuel cell stack system comprises multiple fuel cell sub-stacks, each of which comprises multiple

individual

fuel cell units.

Plates separate

the anode of each fuel cell unit from cathode,

and plates separate

the adjacent corresponding

Germany

fuel cell units in each sub-stack.

The edges of the

a membrane/electrode a soluble, membrane

separator

plate

way

periphery

of each fuel cell sub-stack,

cation exchanger containing acid, phosphonic acid or sulfonic acid at least one side of the membrane finely

of

oxygen-

boundaries

disruption

Ciacchi,

the formation

unit’s

are applied

ET.

121(1-4)

in

with

poor

is not recovered

catalyse

contains

continuity

in air.

Statelonics

be

grain

The

S.P.S. Badwal,

the

of

in to the

the formation

extremely

along

reduction.

large

attributed

loss

with

ion conductivity

The resistivity

and possibly

per

A.E. Steck

AG,

microcracking, grains,

in

up to

of the grain

affected.

has been

date: 25 May

cation exchange

Hoechst

On

reduced

increase

for exposures

boundary

Publication

99124497

The patent describes composite comprising

the grain

of

group chains.

was

After exposure to temperatures (650

the shape

the electrochemical the

the introduction

are useful

date: 20 May

carboxylic 1999

prepared

in the grafted

C. Stone,

Metallised membrane Applicant:

number:

as well

ion-exchange

WO

in

electrically

in fuel cells and electrolysers.

number:

solid electrolytes for a wide range of including sensors, fuel cells, applications, batteries, electrosynthesis reactors and catalytic Patent

are

to a preformed

include

of the

temperatures)

no significant

arc was clearly

increase

exposure

expansion

resistivity

h was observed,

membrane

one or

monomers

are described,

one

electrolytes

ion

commercially can be utilised

than

oxygen

set-up, the exhibited

to

Inc, Canada

in which

or facilitate

leads. an order

of specimens

~1, j3, j3-trifluorostyrenes and trifluorovinyl naphthalenes, which are activated towards

with

about

been

membranes

side of the disc and fitted conductivity

fuel

have

monomers

more

in this way exhibited

to mild

polymerised

O-65 ~01% nanostructured electrolyte powders to form a cermet mix, and then coated on each

assembled

exposed

aromatic

polymeric Preferred

electrical

although

boundary

microstructure

mixtures)

membranes

graft

ion-exchange

disc

In this

and ion-exchange

radiation material.

is mixed

and 5OO”C),

new phase regions

fuel cells

Systems

the 800°C

lower

(minor

for the grain

although

(or

operating

and microstructure

Power

after

similar,

at 800°C

the grain

of

at the grain

behaviour

resistivity

was somewhat

a

development

and the lattice

The

between

oxide

exposure

Ballard

into

to the appropriate

Metallic

The

the

effect)

potential

conductivity.

behaviour

investigated.

Applicant:

solid ionic

of the (Ce,.,Gd,,,)O,,,

interlayers,

lower

to

in

and increases in both the grain

resistivity.

observed are

in

(500-700°C) of their

SOFC

materials

such as ~.,,Sr,,,*M"03'~203)o.l5(CeO,)a,5'

Nanostructured

(major

boundary

(FAVD)

solid

region,

boundary

1000

systems for

vapour

led

resulted

the lattice as a of Ce*+ to Ce3+,

considerably less conspicuous. Hz-N2 atmosphere at lower

1999).

Cathode/electrolyte SOFCs

1000°C

and loss of continuity

boundary

lattice

Lao,&Sro,1SMn03/YSZ

S. Charojrochkul,

turn

boundary a

system.

217-227,

1999).

in

effect)

The

indicate

in overall

the conventional

der

spectroscopy.

new

performance

(Van

at

expansion of of the reduction

microcracks

where structure

The

mixtures

substantial consequence

Lao,8Sro,2C003~Ce0,8

The

bed. I? Argyropoulos,

investigated

Gd,,,0,.9 and La,,.$0,2C003/YSZ, YSZ is 8 mol% Y,O, in ZrOz.

is examined

that comprise

been

flow

heat-exchanger,

cell scale-up

bed

each of the three

,Sr,,~Co03/Ce,,,Gd,,,01,,/YSZ

and cathode

the cell. The model used in current

Lao,,S~o,2Co03~(Y203)o.15(Ce02)0.85~ H2-N2

YSZ and h

divided

metals

which

oxidant

flow-paths

extend

some between

beyond

adjacent

the

forming plates

extending from the plate edge to the centre of the plate, from which oxidant is then distributed to each fuel cell unit. The

heat generated

by the

Fuel Cells Bulletin No.11