E-Vroom! EVs are driving car companies to expand from the auto business

GM launches Tesla-like energy management unit with focus on batteries.

GM Energy’s Home Ultium system. Illustration: GM.

Ever since the auto industry began, firms have pretty much been doing one thing: making vehicles. OK, so Honda HMC 0.00%↑ builds some small airplanes and Toyota TM 0.00%↑ has a line of recreational boats, but the diversions from the basic business have been few and far between.

And then along came EVs. And, of course, Tesla TSLA 0.00%↑…