Hoechst Aktiengesellschaft

Celanese Ventures Gmbh

Sgl Carbon Ag

Basf Fuel Cell Gmbh

Tetsu Yamamoto

Kenji Motosugi

Yuan Liu

Werner Prass

Thomas Stehlin

Akihiko Tokida

Shizuo Ogura

Christoph Roth

Masayuki Arai

Gregor Deckers

Makoto Murata

Victor Trapp

Ruediger Hengl

Markus Leib

Hans-Ulrich Simmrock

A method for producing a polyelectrolyte membrane, including the step of immersing a basic polymer such as a polybenzimidazole in a strong acid having a concentration sufficient to impregnate the basic polymer with six or more strong acid molecules per polymer repeating unit of the basic polymer at a temperature of not less than 30&#xb0; C. for a period of 5 h or less, as well as a fuel battery having the polyelectrolyte membrane. Hence, the times required to immerse the basic polymers in the strong acids can be shortened and the proton conductivity of the polyelectrolyte membranes can be improved.

Method for production of polyelectrolyte membranes and fuel cell

A method for producing a bridged polymer membrane includes the steps of: obtaining a liquid medium comprising a basic polymer having an amino group in a repeating unit, a bridging agent, and a solvent; shaping the liquid medium into a membrane configuration to obtain the shaped membrane; and bridging the basic polymer by the bridging agent in the shaped membrane. A fuel cell has the bridged polymer membrane. The mechanical strength of the polymer electrolyte membrane is improved.

Method for producing bridged polymer membrane and fuel cell

This invention relates to bipolar plates for electrochemical cells, particularly low-temperature fuel cells, with surface modification to enhance through-plate conductivity, processes for improving the surface properties of those bipolar plates, and fuel cell assemblies made with such plates. Graphite-polymer composite bipolar plates with high bulk conductivity are subjected to an abrasive surface treatment to improve the surface contact as well as the reactant transfer to the adjacent gas diffusion electrodes.

Bipolar plates for fuel cell stacks

A method for producing a polymer electrolyte membrane is disclosed. A liquid medium is introduced into a cylinder having an inner surface having a cylindrical configuration. The liquid medium has at least one percent by weight of a polymer electrolyte and a solvent having a boiling point or an azeotropic point ranging from 60 to 220&deg; C. Subsequently, the cylinder is rotated for evaporating the solvent by means of a centrifugal force created by such rotation so as to form a polymer electrolyte membrane having a cylindrical configuration with a substantially uniform thickness on the inner surface of the cylinder. Onto the inner surface of the polymer electrolyte membrane, a catalytic layer containing a catalytic particle may be formed.

Method for producing polymer electrolyte membrane and fuel cell

The present invention pertains to a film for detecting chemical substances comprising a homopolymer or a copolymer having recurring units represented by the following formula (I): ##STR1## wherein X is --H, --F, --Cl, --Br, --CH.sub.3, --CF.sub.3, --CN or --CH.sub.2 CH.sub.3 ; and R.sup.1 is --R.sup.2 or --Z--R.sup.2 ;

Polymer films for detecting chemical substances

An optical sensor apparatus for detecting a vapor of an organic solvent is characterized by a simple structure which allows easy manufacture, high reliability, low cost, compactness in size, and portability. The optical sensor apparatus has a light source unit which emits light for irradiating a polymer thin film formed on a flat reflecting substrate of a sensing element. Light reflected by the sensing element is detected by a light detecting unit. The light source unit, the sensing element, and the light detecting unit are integrally supported by a housing. The polymer thin film which comes into contact with a vapor of an organic solvent causes a change in the thickness and a reflective index thereof. This change is utilized to detect the existence and/or concentration of a vapor of an organic solvent.

Optical sensor apparatus for detecting vapor of organic solvent

A method for identifying a single fuel vapor in an atmosphere of interest that is selected from the group consisting of at least two fuels and that is the sole fuel component of the atmosphere, comprising the steps of: providing a plurality of measuring means that are at least equal in number to the types of fuels that compose the fuel group and which have different sensitivities to the respective fuel vapors; presetting the relationship between the magnitudes of the outputs from the respective measuring means at various fuel vapor concentrations in such a manner that it differs from one fuel vapor to another; placing said measuring means in the atmosphere of interest containing said single fuel vapor as the sole fuel component; measuring the concentration of that fuel vapor; determining the relationship between the magnitudes of outputs as obtained from the respective measuring means; and comparing the thus determined relationship with the preset relationships, thereby identifying the fuel vapor in the atmosphere of interest. This method enables positive identification of a particular fuel vapor without errors. An apparatus for implementing this method is also provided.

Sensor for distinguishing fuel vapors

Optical sensor for detection of chemical species

An optical sensor for detecting gaseous or liquid chemical species including a sensing element having a flat light reflecting substrate and one or more transparent thin films which are organic or inorganic films or high-polymer films and are formed on the substrate. The detection of the gaseous or liquid chemical species is effected by measuring a change in the light reflection characteristic of the sensing element based on swelling of the thin film or a change in its thickness or refractive index or changes in both parameters.

Growing community of inventors

Kawagoe, Japan

Tetsu Yamamoto