1966 Chevrolet Electrovair II: GM's Radical 1960s EV Experiment That Shaped Modern Electric Cars

In 1966, the average price of a gallon of regular gasoline in the U.S. was about 30 cents—equivalent to roughly $3.10 today. The muscle car wars were in full swing, with automakers prioritizing raw power and larger engine displacements. Against this backdrop, General Motors introduced the Electrovair II, an experimental 1966 Chevrolet Corvair four-door hardtop converted to run on electric power.

Never intended for mass production, the Electrovair II served as a rolling test bed to explore the feasibility of electric vehicles for public use. While its launch may seem counterintuitive given the era’s abundant and inexpensive gasoline, the Electrovair II represented a bold step forward in automotive innovation.

As its name suggests, the Electrovair II was not GM’s first foray into electric vehicles. The company had a long history with alternative fuels, including electric trucks marketed at the turn of the 20th century. The first Electrovair debuted in 1964, and GM further expanded its experimental efforts in 1966 with the Electrovan, developed in partnership with Union Carbide. The Electrovan marked GM’s first experimentation with fuel-cell technology.

GM’s ongoing EV development culminated in the launch of the EV1 between 1996 and 1999—the first production electric vehicle from a major manufacturer made available to the general public.

Technical Breakthroughs and Challenges of the Electrovair II

The Electrovair II was a viable electric vehicle capable of highway speeds, with a driving range of 40 to 70 miles. Its acceleration and driving behavior were comparable to those of a gas-powered Corvair of the time. Notably, its maximum range was close to the EPA-estimated 73-mile threshold for the first-generation 2011 Nissan Leaf, which became the first mass-market EV half a century after the Electrovair II’s debut.

Why the Corvair Platform?

GM engineers selected the Corvair platform for the Electrovair II primarily because it was the lightest vehicle in the company’s portfolio at the time. To power the vehicle, they opted for silver-zinc battery cells, a technology more commonly used in aerospace applications. These batteries were chosen for their:

• Relatively light weight
• High peak power output
• Superior energy storage compared to alternatives available in 1966

Drawbacks of Silver-Zinc Batteries

Despite their advantages, silver-zinc batteries had significant limitations:

• Limited lifespan—batteries wore out after approximately 100 charges
• Extremely high cost, estimated at around $160,000 in 1966 dollars

However, the weight savings compared to lead-acid batteries were substantial. The Electrovair II used 286 silver-zinc cells, which occupied nearly all the available space in the Corvair’s front trunk and shared the rear engine compartment with a 115-horsepower motor supplied by GM’s Delco Products Division. The batteries added about 680 pounds to the vehicle’s curb weight. In contrast, GM engineers estimated that using lead-acid batteries would have added roughly 2,600 pounds—equivalent to the weight of another Corvair.

The Electrovair II’s total electrical power output was 26.4 kWh, a modest figure by today’s standards but groundbreaking for its time.