Late last night in Las Vegas, Toyota revealed the new fourth-generation of the world’s best selling hybrid, the Prius. Eighteen years after the debut of the original, the Prius has become an automotive icon with a distinctive look that has become synonymous with battery-assisted cars. Images of the of the new Prius have been leaking out for weeks and by time Toyota revealed the car it was no longer a surprise. All that was really left to reveal were the technical details, but unfortunately those have been kept to a bare minimum other than the news that it will offer a 10 percent boost in fuel efficiency.
As of July 2015, Toyota has sold more than eight million vehicles propelled by a combination of internal combustion and electric drive. Toyota didn’t invent the hybrid electric drivetrain. The basic concept was nearly a century old by the time the first Prius hit the road in 1997. Ferdinand Porsche built a plug-in hybrid in 1900 and engineers from TRW conceived and patented the power-split parallel hybrid architecture in the late 1960s. But it would take nearly three more decades before Toyota engineers sufficiently refined the concept to make it viable for production.
It wasn’t until the late 1990s that the right combination of battery chemistry and computing power was commercially available to make a power-split hybrid sufficiently refined for paying customers. Toyota pioneered the use of nickel metal hydride batteries that had enough energy capacity at a low-enough cost to be practical.
From a design perspective, the new Prius retains the same basic egg-shaped profile as the second and third-generation versions. However, the new model gets a more dramatic look by adopting design elements from the fuel-cell Mirai including the floating roof and front fascia with corner mounted driving lamps that mimic the massive air intakes of the fuel cell model. The 2016 Prius will get more efficient LED headlamps standard.
The basic powertrain architecture is believed to has remained largely unchanged since the beginning but Toyota has continued to refine the system with more component integration and design changes that improve the efficiency of the various subsystems. The same is believed to hold true for the newest edition although the system is lighter than before. No information has been offered about the engine or even the battery system other than it being lighter and more energy dense.
In addition to a base model Prius with a 10 percent boost in fuel economy which should put it at about 55 mpg combined, there will be a new Eco model. The base variant is expected to continue with nickel metal hydride batteries just like the new Lexus RX hybrid. Toyota is bucking the industry trend here where every other major automaker has now dropped NiMH in favor or lithium ion cells even for non-plug-in hybrids. The Prius Eco is expected to use li-ion but Toyota appears to be leveraging its two decades of experience with the older chemistry to keep costs down and help make the Prius profitable.
The new Prius is built on the Toyota New Global Architecture (TNGA) which includes a double wishbone rear suspension layout similar to the recently launched Scion iM. The new suspension setup certainly makes the Scion more dynamically capable and should help make the Prius approach being fun-to-drive, something that has never been the case before. The Prius is 2.4 inches longer, 0.6 inches wider and 0.8 inches which should yield some extra space in the cabin. If you are a fan of the center-mounted instrument display that has been a Prius hallmark for nearly 20 years, you’ll feel right at home in the new edition although the displays now feature higher resolution.
We’ll probably learn more about the Prius at the upcoming Frankfurt Motor Show and in the following weeks leading up to its launch later this fall.
