Electric-Car Mania Turns Battery Makers Into Power Brokers

(Bloomberg) -- Automakers are investing billions of dollars to bring new electric vehicles to consumers in the U.S. and other global markets, but their success hinges on securing the most critical and expensive component: the battery.A handful of companies based in China, Japan and South Korea make automotive-grade battery cells, which has upset the traditional dynamic between carmakers and parts suppliers. These battery giants -- though little known to the general public and relatively new...