Process to manufacture an ion-permeable and electrically conducting flat material, the material obtained according to the process, and fuel cells
OwnerBalthasar Millerinventor
Life of this patent
Estimating the term…
Abstract
A fibrous, flat and ion-permeable material made of synthetic fibers, in particular of synthetically spun fibers such as acrylic fibers or aramid fibers, is processed into staple fibers of a specific length and then fibrillated. In a wet-laid inclined machine (paper machine), the fibrillated fibers are formed into a continuous web and then the web or portions of it are subjected to a temperature treatment to make the web electrically conducting by carbonizing/graphitizing the web through heating.
Claims29
A process to manufacture a fibrous, flat and electronically conducting material made of synthetic fibers, in particular synthetically spun fibers (e.g. acrylic fibers), comprising the steps of
- first fibrillating staple fibers having preferably a specific length;
- forming the fibrillated staple fibers into a continuous web in a paper manufacturing process, preferably by means of an inclined wire wet laid paper machine,
- characterized in that,
- the continuous web is calendared at least once prior to its carbonization and then carbonized/graphitized through heating at a temperature of greater than 600° C., to obtain electrical conductivity.
Non-woven fabric comprising carbonized/graphitized polymeric fibres characterized in that the fabric has a core having a first porosity and at least one cover layer having a second porosity, said second porosity being less porous than the first porosity.
Non-woven fabric according to one of characterized in that, the fabric is micro porous.
Fuel cells containing at least two gas diffusion layers separated by an ionically-electrically conducting layer separating wall (PEM membrane), said gas diffusion layers being coated with at least one catalyst. characterized in that, each gas diffusion layer is formed at least in part from a material having a fibrous core and at least one micro porous flat cover layer on one side of the material that is more dense than the fibrous region and a non-woven fabric consists essentially of carbonized/graphitized polymeric fibres.
Dependencies are inferred from the claim text.