4:50 PM PST · January 27, 2021 Tesla CEO Elon Musk said on the company’s 2020 Q4 earnings call that all engineering work is now complete on the Tesla Semi, the freight-hauling semi truck that the company is building with an all-electric powertrain. The company expects to begin deliveries of Tesla Semi this year, it said in its Q4 earnings release, and Musk said the only thing limiting their ability to produce them now is the availability of battery cells. “The main reason we have not accelerated new products – like, for example Tesla Semi – is that we simply don’t have enough cells for it,” Musk said. “If we were to make the Semi right now, and we could easily go into production with the Semi right now, but we would not have enough cells for it.” Musk added that the company does expect to have sufficient cell volume to meet its needs once it goes into production on its 4680 battery pack, a new custom cell design it created with a so-called ‘tables’ design that allows for greater energy density and, therefore, range.