David J Keyes

US Patent:

7862943, Jan 4, 2011

Filed:

Aug 1, 2008

Appl. No.:

12/184766

Inventors:

Matthew K. Hortop - Rochester NY, US
David John Keyes - Rochester NY, US
Ellen Greifenstein - Darmstadt, DE
Kazuyuki Izawa - Hamamatsu, JP
Kengo Ikeya - Hamamatsu, JP

Assignee:

GM Global Technology Operations, Inc. - Detroit MI

International Classification:

H01M 8/04

US Classification:

429429, 429432

Abstract:

A hybrid fuel cell system that employs a fuel cell stack and an ultracapacitor. A diode is provided on a high voltage electrical bus between the fuel cell stack and the ultracapacitor so that high voltage from the ultracapacitor does not affect the operation of the fuel cell stack. During system start-up, a by-pass switch is closed to by-pass the ultracapacitor so that power from the ultracapacitor can be used to start various system loads, such as a cathode side air compressor that provides air to the fuel cell stack. A 12 volt-to-high voltage converter is employed to provide a low power, high voltage supply from a low voltage battery to the system loads at start-up when the by-pass switch is opened, but before a fuel cell stack switch is closed.

US Patent:

8154242, Apr 10, 2012

Filed:

Mar 26, 2008

Appl. No.:

12/055604

Inventors:

Kristian M. Whitehouse - Rochester NY, US
David John Keyes - Rochester NY, US
Joseph J. Ferrero - Geneseo NY, US

Assignee:

GM Global Technology Operations LLC - Detroit MI

International Classification:

H02J 7/00
H02J 7/16
H01M 8/04
H01M 8/00

US Classification:

320101, 320138, 320118, 320116, 320117, 320119, 429432, 429400, 903908

Abstract:

A fuel cell system that includes a fuel cell stack and an EESD electrically coupled to a common high voltage bus line. The EESD has a higher voltage output than the fuel cell stack, and thus the stack is unable to fully charge the EESD, for example, at system shut-down. In order to allow the fuel cell stack to fully charge the EESD, the EESD is separated into a plurality of separate electrical storage banks having lower voltage potentials. A series of contactors are provided to electrically couple the storage banks in series during normal system operation, and separately charge the storage banks using the fuel cell stack so that they are fully charged. The series of contactors can also be configured so that the storage banks can be electrically coupled in series during normal operation of the system and be electrically coupled in parallel during charging at system shut-down.

US Patent:

20100040931, Feb 18, 2010

Filed:

Aug 12, 2008

Appl. No.:

12/190261

Inventors:

Matthew K. Hortop - Rochester NY, US
Bernd Peter Elgas - Hilbersheim, DE
Robert S. Foley - Rochester NY, US
David John Keyes - Rochester NY, US

Assignee:

GM GLOBAL TECHNOLOGY OPERATIONS, INC. - DETROIT MI

International Classification:

H01M 2/02

US Classification:

429 34

Abstract:

A fuel cell system that includes a single enclosure for all of a fuel cell stack and other stack critical electronics and components, such as power distribution components, voltage monitoring and detecting components, electrical isolation components, etc. The single enclosure offers a number of advantages, such as reduced weight and reduced complexity for service and safety.

US Patent:

20140153932, Jun 5, 2014

Filed:

Dec 5, 2012

Appl. No.:

13/705526

Inventors:

- Detroit MI, US
Michael F. Zawisa - Victor NY, US
Kenneth L. Kaye - Fairport NY, US
Mark A. Buffa - Utica MI, US
David J. Keyes - Rochester NY, US

Assignee:

GM GLOBAL TECHNOLOGY OPERATIONS LLC - Detroit MI

International Classification:

H01M 8/04

US Classification:

398140, 429432

Abstract:

An integrated environmental barrier for protecting the receiver portion of a fuel cell stack health monitoring system. The stack health monitoring system includes a transmitting measurement module and an optical communication module having a receiver. Measurements indicating the health of the fuel cell stack are optically communicated between the transmitter and receiver through the environmentally protective barrier. The environmentally protective barrier is disposed between the measurement module and the optical communication module such that the environmental barrier isolates the optical communication module from the environment contained within the fuel cell stack. The environmental barrier comprises light blocking and light transmitting portions enabling system variation while ensuring signal integrity.