With more than 250,000 BMW plug-in electric vehicles already on global roads, the makers of the ultimate driving machine are now planning to make EV technology an integral part of its brand and production process. BMW is emboldened by seeing sales of its plug-in cars increase by nearly 50 percent this year. “We are preparing our car architectures and our factories to flexibly integrate this technology,” said Oliver Zipse, BMW’s chief of production. “For us, creating that flexibility is the most efficient way to profitably offer electric cars.”