The hydrogen and
fuel cell center
ZBT GmbH

Your Contact

Dr.-Ing. Georg Dura

vice head of department
Micro Systems and Fluid Mechanics

phone: +49-203-7598-2344
g.dura(at)zbt-duisburg.de
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Your Contact

Dipl.-Ing. Jens Wartmann

Head of department

Micro Systems and Fluid Mechanics

phone: +49-203-7598-3336
j.wartmann@zbt-duisburg.de
online form

Micro bipolar plates

For fuel cells in portable applications new methods of production are necessary to provide thin and stable bipolar elements. Therefore innovative materials and manufacturing processes are introduced which offer benefits related to compact packaging, quantity manufacturing, performance as well as costs.

LiGA bipolar plate
ceramic bipolar plate
metallic screen-printed bipolar plate
 

LiGA bipolar elements

In cooperation with the Institut für Mikrostrukturtechnik of the Karlsruher Institute of Technology (KIT IMT) and Forschungsinstitut für Edelmetalle und Metallchemie (fem) currently a concept for novel micro bipolar elements is developed based on a combination of  lithography and electroplating technology (LiGa). Established methods, which are e.g. used for planar process as well as micro electroplating, are adapted to fit the demands of fuel cell technology. Those methods provide yet unused benefits for the production of planar micro fuel cell stacks as passive, self breathing PEMFC. Especially the lithographically based electroplating has to be pointed out. This technique enables the opportunity of a selective and thereby economical integration of key materials like gold to specifically enhance the performance of cells.

The utilization of circuit board materials as base-substrate for all processes offers large opportunities with respect to an cost-effective mass-production of future micro bipolar elements.

 

ceramic bipolar plates

In another current research project in cooperation with the Fraunhofer Institut für Keramische Technologien und Systeme (IKTS), Hermsdorf, bipolar plates based on ceramic circuit boards are being development.  Bipolar plates are built in layers with low temperature co-fired ceramics (LTCC) which are finally sintered. The manufacturing of each layer is done by means of laser cutting of a ceramic tape.

Electroplating technology provides the necessary electric conductivity of the plates through an integration of micro vias. A special benefit of this approach is the possibility of imbedded cooling channels within the bipolar plates.

Due to the high stability concerning temperature and corrosion of the utilized ceramic materials these bipolar plates are especially suited for the operation in high temperature PEM fuel cells.

 

Metallic screen-printed bipolar plates

In cooperation with the Fraunhofer Institut für Fertigungstechnik und Materialforschung (IFAM) metallic bipolar plates based on an advanced 3D-screen-printing process have been developed to fit the demands of fuel cells.

This technology enables the print of undercuts or overprinted hollows within thin elements. These beneficial options are are systematically used for this fuel cell component. Since the physical dimensions of bipolar elements for micro fuel cells are considerable smaller compared to common printing screens multiple elements can be produced simultaneously in each printing step such that large lot sizes are possible. Due to the fine meshing of the applied screens microstructures can be directely generated on the components as well.

Hence, the developed 3D-Metal screen-printing technique is an innovative and volume production suitable process which can be used to produce function-specific and budget-friendly metallic bipolar plates even for other types of fuel cells as well (DMFC, SOFC, MSFC).

The research project 15784 BG of IUTA ("Entwicklung eines 3D-Siebdruckverfahrens zur Herstellung metallischer Bipolarplatten für Mikrobrennstoffzellen", 09/2008 - 08/2010) was funded by the Confederation of Industrial Research Associations (AiF) within the support program “Industrial Joint Research (IGF)” of the Federal Ministry of Econo­mics and Technology.

Last update:  31.08.2016