https://www.reuters.com/article/us-gm-ceo/gm-details-new-electric-vehicles-lower-cost-battery-idUSKBN1DF272 >General Motors Co Chief Executive Mary Barra is set to tell investors on Wednesday about the automaker's plans to launch a new family of electric vehicles in 2021 with batteries costing about 30 percent less than those used on the current Chevrolet Bolt.