Energy Technologies is working to take its fuel cell technology from the laboratory to the battlefield. And the Mansfield-based company hopes to add a few jobs along the way. Since 1992, the company has been producing portable power sources for the most rugged conditions, with Department of Defense as its most interested customer. Now, the company has its sights set on fuel cell technology � a device that could be employed as a portable power plant at a temporary, military tactical facility. In the last three years, Energy Technologies has been awarded three $1-million Ohio Third Frontier grants for its work. The company's long-term goals include adding as many as 200 jobs to a current staff of 72.