Nissan gives its Rogue compact crossover utility a hybrid-electric powertrain option for model year 2017, boosting the estimated fuel efficiency of the front-drive model to 33 mpg city/35 highway and that of the all-wheel-drive version to 31 mpg city/34 highway. That’s an increase of approximately 5 mpg combined city/highway for both the FWD and AWD hybrids versus the standard Rogue.
“The CUV segment is on fire in the U.S. and that’s why we’re putting a lot of emphasis on this segment,” said Ty Webb, Senior Manager of Rogue Marketing for Nissan North America. He said Rogue is poised to become Nissan’s top-selling model, overtaking the Altima midsize sedan.
Rogue Hybrid provides a full EV mode, unlike the milder hybrid systems on the 2014 MY Pathfinder, which ceased production in 2015, and the current midsize Murano CUV.
“The electric-only mode on the Rogue Hybrid automatically engages when the vehicle is coasting at highway speeds up to 75 mph, and for a short time during speeds up to 25 mph,” according to Motohisa Terada, Manager of Electric Powertrain Project Group for Nissan Motor Co. based in Kanagawa, Japan.
Terada and other Nissan technology product experts spoke with Automotive Engineering during a recent ride-and-drive program. While the conventionally-powered 2017 Rogue is powered by a 170 hp (127 kW) 2.5-L gasoline I4, the new Hybrid model features a 2.0-L 4-cylinder gasoline engine generating 141 hp (105 kW) at 6000 rpm and 144 lb·ft (195 N·m) at 3600 rpm combined with a 30-kW (40-hp) e-motor for a combined system rating of 176 hp (131 kW).
Packaging the battery
The Rogue Hybrid driveline uses Nissan’s one-motor/two-clutch Intelligent Dual Clutch Control system in which a wet clutch is located in the traditional torque-converter space between the engine and e-motor and a dry clutch is fitted between the motor and the JATCO-supplied Xtronic CVT. The dry clutch is used only to start-stop the engine. The overall system design allows the engine and e-motor to operate flexibly and offer the electric-only mode depending on load and driving situations.
A Hitachi-supplied 56-cell lithium-ion battery pack is located under the cargo deck, resulting in a slightly higher floor height. That height difference means the standard Rogue’s 18-configuration Divide ‘N Hide cargo system isn’t part of the hybrid vehicle’s cargo bay.
In addition, the second-row seat in the hybrid vehicle doesn’t have 9-in (229 mm) of seat travel like the standard Rogue, according to Brian Wilson, Nissan North America’s Product Planning Department Manager for Nissan Vehicles.
“Battery packaging didn’t affect the cargo area," Wilson said, noting that both the standard and the hybrid Rogue have more than 61 ft3 of stowage space behind the first seating row.
Electric A/C system
Rogue Hybrid’s electric A/C system is an application-first for a Nissan vehicle in North America. Said Terada, “If we used a mechanical A/C system, the A/C would stop during engine idle when the stop/start technology is activated. With the electric system, the flow of cool air isn’t interrupted when the Rogue Hybrid is in an idle stop/start mode.”
Paul Cullen, drivability engineer at Nissan’s Arizona Testing Center, said both the standard hybrid versions of Rogue have similar acceleration G-force curves. “The tuning of the powertrain is not a mirror image between the standard and hybrid Rogue, but the performance will feel similar to a driver,” Cullen said.
Rogue Hybrid’s high-output Li-ion battery pack charges and discharges quickly, contributing to high-speed, precise control of the electric motor and optimum clutch control as well as enabling quiet and quick acceleration, according to engineers.
“We have a great hybrid vehicle that has a nice balance of performance and fuel economy as well as a seamless transition between the electric-only mode and the ICE-only mode,” Cullen said.
Pricing will be announced closer to Rogue Hybrid’s production launch in late 2016. The warranty for the battery pack and inverter unit covers 8 years or 100,000 miles.Continue reading »