As we approach the 25th anniversary of the modern electric car, I would like to reflect on the progress made on widespread adoption of the technology. Electric cars have been around since the 19th Century but became obsolete in the 1930s. I date the modern electric cars (admittedly arbitrarily) to the introduction of GM’s EV1 in 1996. Yes, Toyota was producing the RAV4 EV about the same time, which also was when Norwegian company Think Global, maker of the electric car Th!nk City, was acquired by Ford Motor Co. 

All three ceased production after a few years. What killed the electric car (again)? The same three problems that allowed the internal combustion engine to triumph over electricity (and steam) almost 100 years ago—high initial cost, limited range and long charging time.

Progress has been made on all three fronts, but cost still remains the primary barrier to most consumers. Electric vehicle adoption rates can be directly linked to government incentives worldwide. As incentives are phased out, sales drop.

Perhaps the most progress has been made on vehicle range. The EV1, for example, advertised a range of up to 160 km (100 miles), but customers reported the range was around 100 km (60 miles) under actual driving conditions. Combined with a full recharging time of up to eight hours, most drivers suffered from range anxiety—the fear of running out of charge far away from a charging point.

The tribologist’s contribution to vehicle electrification is primarily to increase range by reducing friction losses. Possibly the greatest innovation of the EV1 was the regenerative braking system. When slowing the vehicle, instead of just converting kinetic energy to heat, the electric motor functions as a generator to recharge the battery. Virtually every modern electric car uses some version of this system.

Also, a feature of the EV1 was a single-speed reduction gear, allowing the electric motor to run at higher speed, closer to its peak efficiency, when the vehicle was cruising. The gear fluid was GM’s conventional automatic transmission fluid, in spite of the fact that there was no shifting, and the loads on the gears were highest at low speed (as opposed to the internal combustion engine which produces high load at high speed).

The next big challenge for the electric automotive tribologist lies with the gear lubricant. The current generation of lubricants are not optimized for high load at low speed. Improved gear lubricants could open the pathway to greater range and improved vehicle performance.