Employees are seen at the assembly line of lithium-ion batteries for electric vehicles (EV) at a factory in Huzhou, Zhejiang province, China. ReutersTwo Chinese battery makers are set to surge as international demand for electric automobile batteries might multiply by approximately 30 times in the next 20 years, Goldman Sachs analysts stated in a March 18 note.The company updated its projection for sales in Europe and the U.S.– the experts now expect 47%, or nearly half, of all cars sold worldwide in 2040 will be electrical, increasing demand for batteries.If sales wind up surpassing that base case scenario, there might even be a shortage in batteries in 2025, the report said.Here are the numbers behind the more than 70% gains Goldman anticipates for a minimum of one Chinese battery company: