It sounds so simple. Just combine oxygen and hydrogen in an electrochemical reaction that produces water and electricity, and you'll have a clean, efficient power source. But scientists have spent decades-and billions of dollars in government and industry funding-developing the fuel cell. There have been successes and serendipitous discoveries along the way, but engineering a fuel cell that is both durable and affordable has proved extraordinarily difficult. Overpotential charts the twists and turns in the ongoing quest to create the perfect fuel cell. By exploring the gap between the theory and practice of fuel cell power, Matthew N. Eisler opens a window into broader issues in the history of science, technology, and society after the Second World War, including the sociology of laboratory life, the relationship between academe, industry, and government in developing advanced technologies, the role of technology in environmental and pollution politics, and the rise of utopian discourse in science and engineering.