During the 1960s, GM was looking seriously at electric cars. Gas may have cost only about 34 cents a gallon, but Americans were more concerned about potential air pollution than fuel economy, according to a GM overview on the Electrovair. So why did GM abandon the project? Let’s find out.
The Electrovair II was an improved version of 1964′s Electrovair I. Both were based on the rear-engine gas-powered Chevrolet Corvair, whose design provided a convenient location for the batteries. The large battery pack went under the hood, while the electric motor drove the wheels from the back of the car. “The GM electric vehicle concept is based on the belief that an electric car should have performance compatible with modern expressway driving,” press materials for the car said.
The Electrovair II used silver-zinc batteries and they were expensive and wore out quickly, as the carmaker admitted at the time. Performance was similar to the gas-powered Corvair, but range was a problem with the car needing a recharge after 40 to 80 miles.
The battery powered 1966 Electrovair II concept was a test bed for motor and control developments. The battery pack, in a 532-volt array, located in the front compartment of a 1966 Corvair Monza sport sedan. The silver zinc batteries delivered high peak power and provided good energy storage but they were costly and were worn out after 100 recharges. The battery pack was connected to a 115 horsepower AC-Induction Motor that produced approximately the same performance as a conventional gasoline powered Corvair. A tank full of gasoline would propel a Corvair 250-300 miles. Top speed was 80 m.p.h.
According to the Society of Automotive Engineers (SAE) paper #670175, “Electrovair – A Battery Electric Car,” the 1964 Corvair was chosen for the first conversion to an electric drive. Quoting from the SAE paper:
It was the lightest GM production car available, and its rear drive was ideal for a compact and simple motor installation. The problems encountered in Electrovair I suggested many basic improvements in the electric drive system. As a result we started on an improved motor control system. Soon it became apparent that building an entirely new car would be easier than upgrading the first car. Thus, the decision was made to build Electrovair II starting from a 1966 Corvair
Cost and range would be the major undoing for the electric car in the 60’s. With pending emission and safety regulations set to become law during the late 60’s, the decision to drop any further research on electric vehicles, and to shift these funds to other more relevant projects was prudent.
Image Source: Autoblog Green/Sam Abuelsamid