Tesla also had a 48 percent share of all EV registrations for the month, down from 56 percent at the same time last year as EV competition grows. EV registrations overall in July

Hoping to spark higher EV sales, General Motors Co. is offering owners adapters to access the Tesla Supercharger network.

Adaptors will first be available in the United States, but Canadians can place pre-orders starting today. The adaptor will cost $310 CAD (US$228), which means it retails for about the same as the American one at current exchange rates.