Fujitsu Develops High Capacity Micro Fuel Cell Technology

Tokyo, Japan, Jan. 26, 2004 - (JCN Newswire) - Fujitsu Laboratories Ltd.
today announced the development of a new fuel-cell material
technology that enables the use of 30% methanol - highly concentrated
methanol - as a fuel source, as well as a prototype power unit that
incorporates the technology. This technology enables much higher power
capacities for passive micro fuel cells (*1) and realizes longer
runtimes for mobile devices such as notebook PCs, PDAs and mobile
phones. 

[Background]
As notebook PCs, PDAs and mobile phones evolve to deliver higher
performance and greater functionality, they have also come to demand
more electrical power. But the lithium-ion (Li-ion) batteries commonly
used today have already approached the limits of their capacity, which
has made the development of a higher-capacity 
power source a matter of greater urgency.

Micro fuel cells, envisioned for use in mobile devices, generally use
alcohol solutions as fuel. In terms of energy density, these fuel cells
offer up to 5-10 times the power per unit weight of a Li-ion battery.
From the user's perspective, micro fuel cells have advantages in that
they offer cheap and easy means to power 
electronic devices by simple refueling, enabling continuous use when
traveling with no access to the power grid. 

[Technological Challenges]
Passive systems are best suited for micro fuel cells to help keep the
package compact and light, as they do not require fuel pumps or
circulatory fans. Thus, in order to obtain long runtimes without such
functions, the fuel cells must be able to handle concentrated methanol
as its fuel. 

To date, micro fuel cells mainly have employed fluorinated polymers for
their solid electrolytic material. But fluorinated electrolytes are too
readily permeated by the methanol molecules in the fuel, so that when
concentrated fuels are used, fuel is lost in the generating process and
power capacity suffers, and the sub-reaction 
of methanol and air drastically reduces wattage, creating a problem
known as methanol crossover. 

[Fujitsu's New Technology]
Fujitsu developed a new material technology for the membrane electrode
assembly (MEA) (*2). An aromatic hydrocarbon solid electrolyte material,
which allows slow methanol permeation, is covered with a high density of
highly active platinum-based nano-particle catalyst with methanol
blocking properties. This reduces the total MEA methanol crossover
effect to one-tenth that encountered with typical fluorinated polymers.

[Benefits]
This new material technology for MEA enables the direct use of methanol
concentration of 30%, previously too high to use, resulting in greater
capacity from passive fuel cells. Applying this technology in a
prototype micro fuel-cell system with 300ml of 30% methanol enables a
notebook PC to run for eight to ten 
hours. Furthermore, the prototype fuel cell has been slimmed down to a
thickness of a mere 15mm, while delivering power output levels of 15
watts. 

[Future Development]
Fujitsu plans to continue developing high-performance materials and
refining its manufacturing techniques to develop micro fuel cells that
are even more compact and deliver even longer operational run times.

[Notes]
*1. Passive fuel-cell system
A fuel-cell system that uses no fuel-supply pumps or circulatory fans,
relying entirely on gravity and natural convection to circulate fuel and
air, this is ideal for small, lightweight systems 

*2. Membrane electrode assembly
A composite power-generation unit consisting of an electrode catalyst
layer and a film (membrane) of a solid electrolytic material, which is
the basic unit of a fuel-cell system

* All company names mentioned may be trademarks or registered trademarks
of their respective holders and are used for identification purpose
only.



About Fujitsu Laboratories Ltd.

Founded in 1968 as wholly owned subsidiary of Fujitsu Limited, Fujitsu
Laboratories Limited is one of the premier research centers in the
world. With a global network of laboratories in Japan, China, the United
States and Europe, the organization conducts a wide range of basic and
applied research in the areas of Multimedia, Personal Systems, Networks,
Peripherals, Advanced Materials and Electronic Devices.For further
information, please visit the Fujitsu Laboratories Ltd. home page at:
www.labs.fujitsu.com/en/ <http://www.labs.fujitsu.com/en/> 

Contact
[Technical Contact]
 Functional Organic Materials Lab.
 Materials & Environmental Engineering Laboratories
 Fujitsu Laboratories Ltd.
 Tel: +81-46-250-8257 (direct)
 e-mail: organic_mat@ml.labs.fujitsu.com