The article looks at how fuel cell cars work and how many have been made over the years. They wanted to see what makes these cars tick and how big their fuel cells are. After studying over 100 different fuel cell cars, they found that most pure fuel cell cars have fuel cells between 80–100 kW, while hybrid cars have smaller fuel cells ranging from 20–100 kW. This research gives us a better understanding of how fuel cell technology has evolved and what sizes work best in different types of vehicles.