Written by Jack Ewing On a frigid day in early January, as she worked in her office in the Boston suburb of Billerica, Massachusetts, Siyu Huang received a two-word text message. “Spinning wheels,” it said. Attached was a short video clip showing a car on rollers in an indoor testing center. Story continues below this ad There was nothing remarkable in the video. But to Huang, the CEO of Factorial Energy, the video was a milestone in a quest that had occupied a decade of her life. Huang, her husband, Alex Yu, and their employees at Factorial had been working...