As the company shows off its electric-vehicle strategy at an event in San Francsico, CA, General Motors is also saying it will have 500,000 electric or hybrid vehicles on the road by 2017, according to the Detroit Free Press.

The company's main focus will be vehicles that plug in, according to Mary Barra, senior vice president of global product development.

"The plug-in offers a unique opportunity to change the way people commute," she says. "Plug-based solutions will play a significant role in our technology portfolio going forward.

According to the article, the Chevrolet Volt's lithium-ion battery pack, which allows cars to travel 38 miles on a single change of electricity, will be an important part of reaching that goal, too, as wll vehicles integrating eAssist, which uses an electric motor.