The best-selling plug-in hybrid (PHEV) in Europe makes its North American debut this Fall and was on display at the 2016 New York Auto Show. Americans may be surprised to know it's the Mitsubishi Outlander PHEV, which has sold some 50,000 units on the continent. And while the plug-in SUV didn't receive the same trumpets-blaring intro as Toyota's new Prius Prime at the Javits Center, the vehicle brings significant hybrid technology and market potential.
Plug-in hybrids have an obvious appeal to OEMs because they earn CAFE (Corporate Average Fuel Economy) credits that approach those given to battery EVs, enabling the automakers to sell more conventional vehicles.
Outlander aims for 20-mi EV range
Europe's plug-in sales leader is built on a 105.1-in (2668 mm) wheelbase with an overall length of 184.5 in (4684 mm). The PHEV battery pack and control electronics consume floor space, so Mitsubishi jettisoned the third-seat row—not a serious loss, as the third row passengers had only 28.2-in/716 mm of legroom to begin with.
One of the Outlander's important features is the full-time all-wheel-drive system. It uses the two 60-w electric motors for the hybrid configuration, one motor per axle. The AWD is integrated with the S-AWC (Super-All Wheel Control) that was adapted from the Lancer Evolution, a performance car discontinued after the MY2015.
Outlander uses the electric motors in conjunction with the electronic stability system/anti-lock brakes to distribute power to the wheels. Because the system is AWD, the only available operating modes are EV, parallel hybrid (gasoline engine with electric assist) and series hybrid (EV with the generator in operation).
As shown in NY, the Outlander PHEV had a 12-kW·h lithium-ion battery pack. Mitsubishi's U.S. officials are "reasonably confident" the same battery spec will be used in the U.S. model, but they are uncertain about the specific pack and control electronics module array. In fact, Automotive Engineering was told to completely ignore the European specifications, which include a 32-mi (51 km) EV range.
The combustion engine is the 2.0-L also used in the Outlander Sport. Although Mitsubishi describes it as "high efficiency," it doesn't operate on the Atkinson cycle (late intake valve closing). The reason apparently is the issue of getting significant Atkinson operation while integrating with the front and rear motors and AWD system.
Mitsubishi's engineering team is aiming for 20-mi (32 km) EV range, according to a company official. He added that the electric-drive package is being "tuned" very differently for the U.S. market. The objective is to improve launch and response in other modes, which could require a faster battery discharge rate during hard acceleration in EV mode. As configured for Europe, the Outlander can run in EV mode up to 70 mph (112 km/h).
The batteries are supplied by Lithium Energy Japan, a joint venture between GS Yuasa and Mitsubishi Motors Corp. It also is the battery source for the I-MIEV, the price leader among electric vehicles.
The Outlander PHEV was tested for durability in the 2015 Portalegre Baja 500, a Portuguese rally in which it finished third. The race vehicle's power system was slightly modified, using a 16 kW·h battery pack and control module changes for higher performance, including acceleration in EV mode up to 100 mph (160 km/h).
Prime time: lower cost, faster recharge
While the Chevrolet Volt's 53-mi (85-km) range on battery power only is highest for a plug-in vehicle, the competition apparently has decided that the sweet spot of the market is about half that range. That's the case with Toyota's new Prius Prime, its smaller battery pack helping to reduce systems cost and reduce recharging time (the Prime recharges on 120-V in 5.3 h, vs. 13 h for the Volt). And the smaller pack helped designers create a more commodious interior and provide savings that in turn permitted standard features such as heated front seats and wireless phone charging.
The heated seats are particularly important, and combined with a Prime cabin pre-heated on household electricity before a winter drive, should result in much lower use of battery capacity and longer EV range. The heating system electric draw on electric vehicles has been shown to cause a major reduction (as high as over 40%) in winter EV range.
And also for the Prime, there'll reportedly be a price premium of significantly less than $5000 over the standard Prius. If the pre-heating and heated seats deliver the anticipated 22-24 mi (35-38 km) all-electric range in winter, that would be much higher than the 11.4 mi (18.3 km) recorded by Automotive Engineering during 2011 winter testing of an early pre-production Prius PHEV with heat on (http://articles.sae.org/9326/).
As additional PHEVs come to market, Toyota recognizes that the Prius brand name might need marketing muscle behind it, so it promises to make the Prime the "best value" in the class. This meant bold styling and the addition of independent rear suspension (replacing a twist beam), which should improve the ride.
Toyota said it believes that 22 mi on electricity is a range that will satisfy a majority of commuters and with an increasing number of charging stations, that many buyers will be able to charge during working hours. Toyota has an arrangement with ChargePoint, a company with some 27,000 locations, mostly in the U.S. More than half will be free to Prime drivers. (For more on the Prius Prime, see http://articles.sae.org/14700/.)
The engine in all Prius models is the 1.8-L Atkinson cycle I4, for which Toyota now claims 40% brake thermal efficiency, over 30% higher than a modern but conventional Otto cycle engine. The contemporary interpretation of the Atkinson cycle increases efficiency by using infinitely-variable valve timing to effectively increase the length of the power stroke. Use of more of what's left in a power stroke normally would lead to performance weaknesses, but the electric assist of the battery hybrid fills in any gaps. The ICE also has a more efficient electric water pump, new cooled EGR system and exhaust heat recovery to speed engine warm up.Continue reading »