A man in a Mercedes drives up to a Bangkok forecourt, cash in hand, ready to buy an electric vehicle he hadn’t planned on owning. Southeast Asia’s EV revolution has found a new accelerant. “He was afraid he wouldn’t be able to fill up his car any more,” said Samart Prakotkancharna, managing director of Ratchapruek P Car Centre in Thailand’s capital, describing the scene that played out on his forecourt. Cash buyers had been streaming in all week, spooked by rising diesel prices and hunting for...