system suitable for operating with

gas fuels or alternatively directly

with liquid fuels, such as methanol,

dimethoxymethane o r

tr imethoxymethane. The u s e of

these l iquid fuels permits thestorage of more energy in less

volume, while at the same time

eliminating the need for handling

compressed gases, which further

simplifies the fuel cell system. The

electrical power output of thedesign can be further increased by

adding a passage for cooling the

stack through contact with a

coolant.

Patent number: WO 99134467

Publication date: 8 July 1999

Invent0rs:A.J. Cisar, D. Weng, O.J.

Murphy

Solid polymer electrolytefuel cellApplicant: Fuji Electric Co Ltd,

JapanA solid polymer electrolyte [PEM]

fuel cell characterised by high

performance, compact size and low

cost is described which prevents

condensation and liquefaction o f

moisture in the reactant gases, andfacilitates uniform cooling in the

electrode planes of the unit cells.The unit cell structure including

separators, each includes oxidant

gas, fuel gas and coolant inlets and

outlets. The inlets are arranged near

the edge, and the outlets in the

centre, of the separators. The

oxidant gas, fuel gas and coolant are

made to flow from the edge to the

centre such that the temperatures of

the oxidant and fuel gases arehigher near the reactant gas outlets.

A continuous coolant flow path is

provided by forming protrusions in

the reactant gas conduits.

Patent number: US 5922485Publication date: 13 July 1999

Inventor: Y. Enami

Co-sintering of multilayerSOFC stacksApplicant: The Dow Chemical Co,

USA

A multi layer fuel cell stack is

described which comprises fuel cell

units each having an electrolyte

layer between anode and cathode

A

layers, a pair of buffer layers, and an

interconnect layer. The buffer layers

are interposed between each of the

electrodes (anode and cathode

layers) and the interconnect layer,

to improve the electrical

conductivity and mechanicalbonding characteristics between

layers. The buffer layers have theadditional effect of physically

separating the layers and preventing

interdiffusion among chemically

incompatible components during

co-sintering. The materials are

selected for the layers such that the

fuel cells are co-sinterable at

relatively low temperatures.

Patent number: US 5922486

Publication he: 13 July 1999

Inventor: Y.-H. Chiao

Anode electrocatalyst forfuel cellA p p l i c a n t s : Tanaka Kikinzoku

Kogyo KK, Japan; M. Watanabe

(Japan); Stonehart Associates Inc,

USA

The patent describes an anode

electrocatalyst for a fuel cell

comprising an ahoy of at least oneo f tin, germanium andmolybdenum, and one or morenob le metals selected frompla t inum, pal ladium andruthenium. The t in , germanium

and/or molybdenum has the ability

of depressing the carbon monoxide

poisoning of the noble metal, so

that fuel containing a relatively

high CO content may be supplied

to a fuel cell equipped with such an

anode, which is otherwise liable to

be poisoned.Patent number: US 5922487

Publication ake: 13 July 1999

Inventors : M. Watanabe, Y.

Yamamoto

CO-tolerant fuel cellelectrodeApplicant: Exxon Research &

Engineering Co, USA

The patent describes a CO-tolerant

fuel cell electrode formed from acarbon-supported, platinum-dispersed, non-s toichiometr ichydrogen tungsten bronze electrode

catalyst of the form Pt-HxWO,

with 0.05 < x < 0.36. The electrode

catalyst is capable of oxidising CO

at very low potent ials , and is

sequentially formed from stable

precursors. The catalyst is formed

by deposi t ing a tungsten oxide

source (pertungstic acid, WO,,

H,W04, W O , , Na2W04 o r

mixtures of these) onto a carbon

support, which has a surface area inthe range 100-500 m2/g and has

lo-40 wt% platinum particles in

the size range 20-30 A dispersed on

it. The tungsten oxide source is

then subjected to a reducing

atmosphere.

Patent number: US 5922488

Publication dute: 13 July 1999

Inventors: E. Marucchi-Soos, D.T.

Buckley, R.J. Bellows

Fuel cell/POX reactor withoxygen enrichmentApplicant: H Power Corporation,USA

The patent describes a combined

cycle system with enhanced

efficiency The system comprises a

top stage - such as a fuel cell, partial

oxidation reactor or heat engine -

and an oxygen-enrichment device -

such as a temperature swing

adsorption device or a chemical

reactor bed - as its bottom stage.

The bottom stage uses waste heat

produced by the top stage to enrich

the oxygen content of air fed to thebottom stage, to produce an

oxygen-enriched gas mixture as the

bottom stage output. This output

mixture const i tutes a superior

oxidant which is fed back as the

input to the top stage, enhancing

the energy conversion efficiency,

cheapness and compactness of the

combined cycle system when

compared to ordinary fuel cells,

partial oxidation reactors and heat

engines that use non-enriched air astheir oxidant input.

I)atent number: US 5925322

Publication d?te: 20 July 1999

Inventor: J. Werth

Fuel cell generator system

Applicant: Toyota Jidosha KK,

JapanThe fuel cell generator systemdescribed in this patent carries out

the appropriate control functions to

ensure a high electrical output even

when the electrode catalyst is

poisoned. An electronic control unit

monitors the output voltage of the

fuel cells, the concentration of

carbon monoxide in the fuel gas, thetemperature of the fuel cells, and the

pressure of the fuel gas. When the

output voltage drops by apredetermined amount, and the

concentration of CO measured by a

CO sensor indicates poisoning of the

catalyst on the fuel cell anodes, the

temperature of the fuel cells is

gradually increased. The pressure of

the fuel gas is also gradually

increased, enabling the partial

vapour pressure in the fuel gas to be

kept constant even though thetemperature of the fuel cells has

increased. Keeping the partial vapour

pressure in the fuel gas at a constant

level prevents the partial pressure of

hydrogen in the fuel gas from being

reduced, ensuring a continuous

supply of hydrogen to the anodes.

Patent number: US 5925476

Publication date: 20 July 1999

Inventor: S. Kawatsu

w Fuel Cells Bulletin No. 13