Patents by Inventor Christina M. Johnston

Christina M. Johnston has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Reversible shunts for overcharge protection in polymer electrolyte membrane fuel cells
    Patent number: 11515555
    Abstract: Described herein is a polymer-electrolyte-membrane fuel cell (PEMFC) that incorporates a shunt into the membrane separator that becomes electronically conductive around a well-defined anodic onset potential, thereby preventing excessive anodic potentials at the positive electrode that would otherwise drive deleterious parasitic reactions such as catalyst dissolution or catalyst and carbon oxidation.
    Type: Grant
    Filed: May 6, 2020
    Date of Patent: November 29, 2022
    Assignee: ROBERT BOSCH GMBH
    Inventors: John F. Christensen, Christina M. Johnston, Yelena Gorlin, Sondra L. Hellstrom, Michael Metzger
  • REVERSIBLE SHUNTS FOR OVERCHARGE PROTECTION IN POLYMER ELECTROLYTE MEMBRANE FUEL CELLS
    Publication number: 20210351426
    Abstract: Described herein is a polymer-electrolyte-membrane fuel cell (PEMFC) that incorporates a shunt into the membrane separator that becomes electronically conductive around a well-defined anodic onset potential, thereby preventing excessive anodic potentials at the positive electrode that would otherwise drive deleterious parasitic reactions such as catalyst dissolution or catalyst and carbon oxidation.
    Type: Application
    Filed: May 6, 2020
    Publication date: November 11, 2021
    Inventors: John F. Christensen, Christina M. Johnston, Yelena Gorlin, Sondra L. Hellstrom, Michael Metzger
  • Catalytic oxidation of dimethyl ether
    Patent number: 9334575
    Abstract: A composition for oxidizing dimethyl ether includes an alloy supported on carbon, the alloy being of platinum, ruthenium, and palladium. A process for oxidizing dimethyl ether involves exposing dimethyl ether to a carbon-supported alloy of platinum, ruthenium, and palladium under conditions sufficient to electrochemically oxidize the dimethyl ether.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: May 10, 2016
    Assignee: Los Alamos National Security, LLC
    Inventors: Piotr Zelenay, Gang Wu, Christina M. Johnston, Qing Li