It was back during her middle school years when Denise Gray found the inspiration that would eventually lead her to her current post as director of energy storage systems at General Motors, where she leads the development of battery technologies that will power the Chevrolet Volt. While studying in an inner city classroom in Detroit, one of Gray's teachers, Mr. Oliver, noticed her ability to excel at subjects that revolved around math and science. "He told me, ‘You should be an engineer.' I had no idea what that meant, but he was a good teacher, who took me to my first math competition, where I realized this was what I was meant to do," Gray says. Mr. Oliver further encouraged Gray to attend Detroit's Lewis Cass Technical High School, a magnet school focused on teaching advanced science and the arts, where she focused on courses in electrical and electronics engineering-she was one of only two females who took part in the classes.
Her interest in science piqued, Gray received an invitation from GM to join its high school co-op program, which allowed students to spend 3.5 hours each day at the automaker's laboratories at its Technical Center in Warren, MI: "When I started as a co-op student, I worked in the same building I am working out of now, but back then I worked on radio systems, clusters, lighting and a little bit in engine controls with advanced engineers to make sure the various components met our requirements." During one of her co-op assignments, a female engineer said it would be important for Gray to learn how to drive a vehicle with a manual transmission. After a couple of lessons on the basics, the engineer left Gray alone on GM's truck test loop and told her she'd be back if Gray did not show up at the office by quitting time: "I went up and down the loop in a [Chevy] Citation, which was a rough transmission to drive." After her Cass Tech and co-op days were over, Gray attended the General Motors Institute (now Kettering University) and worked at the Chevrolet Engineering Center while obtaining her BS in Electrical Engineering.
As one of only a few female African-Americans in GM's engineering ranks, Gray knew she had to think outside the box when it came to assignments. During her early years, she worked in the electronics labs and on software controls, at a time when 90% of vehicle components were mechanical or hydraulic. "I have always felt the need to bring something different to the table, not only as a person, but what I worked on, and that has given me the ability to focus on the task at hand and get the job done without putting an emphasis on what's happening around me," she says.
After working on a number of assignments throughout GM-including time at the proving grounds, in foundry operations and working at a Gear and Axle plant in Detroit (now home to American Axle)-Gray had the opportunity to work on the development of engine controls for the third-generation small block V8-first used in the C5 Corvette-an assignment that she says was her most exciting. "Everything was new, the software, the controls, the emission systems, the diagnostics; it was leading edge. We put electronic throttle control systems in that engine and moved away from the conventional throttle body linkage. I will forever put that project up on my mantle because it had the combination of high-technology and building a new team to pull it off," she says.
Her last assignment in GM's Powertrain organization involved overseeing development of the transmission control systems for the six-speed automatic gearbox that's now used in a wide array of GM vehicles. Gray received word from her boss the automaker was about to embark on something that would truly revolutionize the traditional product development, design and powertrain infrastructure. During her initial interview with a team of executive directors, they laid out what was an ambitious plan to grow GM's hybrid battery development program into the E-Flex vehicle architecture, the backbone for all of the automaker's range-extending electric vehicle programs. "The position as they described it sounded awesome. It was going to be a cross-organizational job with roots in Powertrain organization, along with the need to understand the electrical side of vehicle systems and the overall vehicle development process. As they continued to talk about it, I got more excited about the opportunity," Gray says.
Since obtaining the assignment in December 2006, Gray has been working tirelessly to assure that GM can live up to its promises of developing a battery that can withstand 150,000 miles of operation, with no room for error in daily operation, over varying operating conditions and cycles. "My biggest challenge is there's not enough time in the day," she says. Her involvement in such a critical project has propelled her to heights she never expected, having routine contact with GM's highest ranking executives, including Chairman Rick Wagoner and Vice Chairman Bob Lutz and Fritz Henderson. "They have made sure all the support I have ever needed is there," she says. When she first took on her role, Gray sat down with GM engineering boss Jim Queen to discuss the E-Flex program and how much money would be available: "He told me, ‘Denise, you probably can't understand how much work is coming at you and when you estimate what you need you want to put a multiplication factor on that.'"
Among her biggest surprises has been the openness in which battery system suppliers, some of which have never supplied to the auto industry before, are sharing their latest technologies. This new contingent of suppliers still has to learn the performance requirements for automobiles are much more strenuous than consumer electronics. She points out that while lithium-ion batteries are fairly mature in consumer electronics, the batteries are (1) small and (2) have a warranty of about a year. Neither characteristic is suitable in automotive.
Gray is hopeful the Volt and E-Flex projects will help reenergize an industry that's been battered by a weak economy and endless restructurings by focusing investments on new technologies that can positively impact the environment and change the way consumers interact with their vehicles. "I think that's why the Volt and the platform have resonated with so many people is because it is intuitively obvious and this is a logical place for the industry to invest as opposed to the traditional types of things, which have leveled off," Gray says.