DETROIT—General Motors will expand production and sales of the Chevrolet Bolt electric vehicle. At the same time, GM is expanding battery production for the vehicle from South Korea to a new factory in Michigan.

In a blog post on LinkedIn on Wednesday, GM’s CEO Mary Barra said the Bolt may be more popular with buyers than the automaker expected. Supplies are concentrated in California, and the car is in short supply in other parts of the U.S. Until recently, Canadians had to wait a year to buy a Bolt EV.

The company announced last spring that it will expand production of the car by 20 percent. Expanding battery production near the Bolt’s final assembly plant in Orion Township, MI, is a significant step in that effort.