 Mercedes-Benz Group AG RIVN, 7.94 MBG, -2.89 DAII, 3.17 and Rivian Automotive Inc. RIVN, 7.94 said Thursday they agreed to form a joint venture to manufacture electric vans in a new electric-only production facility to be built near an existing MercedesBenz site in Europe. The two car companies plan to produce one model based on MB Vans electric architecture from Mercedes and a second model based on the second generation electric-van, Rivian light van RLV platform. 