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2011 Hyundai Sonata Hybrid - Thom Cannel's Review

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2011 Hyundai Sonata Hybrid

TOTAL KNOWLEDGE: Hyundai Buyers Guide

By Thom Cannel
Senior Editor
Detroit Bureau
The Auto Channel

Hyundai’s first hybrid is also the fist hybrid design we can cautiously approve of. It delivers good fuel economy and pretty decent ride and handling without the kinds of compromises that deliver economy without pleasure. What’s remarkable is a real plug-and-play design. While using a 2.4-liter Atkinson-cycle engine (same engine type as Ford, Honda, Toyota), it is the rest of the architecture that impresses us. Specifically it is the way the transmission and e-motor (electric power motor) are configured, and the first use of lithium-ion batteries in a hybrid.

Don’t misunderstand our long term mistrust of hybrids; any car with two power sources and a costly and heavy battery can never be as inexpensive, nor as elegant as a vehicle with one engine. However, hybrids can be smarter than they have been. Until Sonata, hybrids injected their electrical power into the drive train through an intricate set of gears adding friction, complexity, and expense. And hybrids are elaborate indeed with construction that stuffs electrical motors into transmission cases, or adds monumentally complex planetary gears to move power from one place to another. Yet, as Toyota, Honda, and GM have proven, it works. Unfortunately, in these examples, to change engines—as in 2.0-liters to 3.0 liters or I-4 to V-6—you have to reengineer the entire system. That means a different transmission case, or different gear sets; different everything at a very nasty increase in engineering time and expense, and greater parts and assembly complexity. In other words, it has to cost even more.

Hyundai’s Sonata Hybrid is the first hybrid from the Korean company, and part of its Blue Drive, low carbon emissions strategy. It uses no complex gears set at odd angles, no electric motor-filled transmission. Instead, the Sonata Blue Drive sandwiches its e-motor directly engine and transmision which means the package is small, and easily adaptable for a variety of engines from four cylinders to V-8. This design uses a thin, permanent magnet synchronous electric motor coupled to the driveshaft at the front of the automatic transmission, thereby capturing space normally occupied by a torque converter. With this system, when a new product is needed a more powerful e-motor can be applied to an existing transmission and engine, or the same e-motor might couple to a different powertrain, diesel, for instance. If highway fuel economy alone was was the issue, a new transmission with seven or eight speeds could be substituted for the six-speed used today. It’s very slick and not much different, conceptually, than building your own club sandwich from a variety of meats, cheeses, and veggies.

The fuel economy benefits of hybrids rests upon the e-motor as it drives the vehicle up to about 30 mph. Hyundai’s design can, with proper technique, tail wind or downhill slope, run electrically up to 62 mph (depending on how fully the battery is charged) and achieve an electric + gasoline EPA rating of 40 mpg. Hyundai, of course, has a different idea of what makes a hybrid more valuable to potential owners. Instead of maximizing competency in urban stop-and-go drive cycles they focused on mid-range and highway operation. Hyundai quotes SAE research which says 58% of driving is on highways. Thus their emphasis on mid-range lane change and highway passing power add-ins over stop-and-go.

Another departure is in body design. Sonata Hybrid looks like a Sonata sedan, not the wedges familiarized by Toyota’s Prius or Honda’s Insight. Instead, Hyundai’s Sonata is characterized by subtle aerodynamic features like louvers that can shut off air flow into the radiator during all-electric operation or when the internal combustion engine doesn’t need cooling air flow. More easily seen is a slightly different rear bumper that sculpts airflow a bit more cleanly and a front fascia that also improves air flow specific to its hybrid operation. Exterior features that don’t change aerodynamics, but make the hybrid more identifiable, are LED daylight running lights and LED tail lamps, chrome body side moldings near the bottom of each door, and of course, Blue Drive badges.

Inside the car, every Sonata Hybrid has brushed aluminum trim around the center stack and an electroluminescent instrument cluster. Centered between the speedometer and tachometer is a 4.2” LCD trip computer that displays the chosen gear and an energy-ecology scorecard to assist you in maximizing fuel economy, should you so choose. The base car has every option from the Sonata GLS, plus its hybrid-only items including power seats, rear floor vents, driver’s key recognition and push-to-start, dual automatic climate control. There is one high-technology option package to increase your digital connection to the car. Should you opt for that premium technology package, its navigation screen also displays alternative views of hybrid functions as well as rear backup camera images. In this single upgrade package you get a premium Infinity sound system, HD radio, a large panoramic tilt/slide sunroof, heated leather seats for the driver and passenger seats along with rear bottom cushion heaters, and a few detailing additions like auto-dimming mirror, a digital compass, HomeLink garage door opener, and what Hyundai calls premium door sill plates.

Today’s hybrids, all of them with gasoline engines, employ a modification to the engine’s combustion behavior called the Atkinson cycle. Hyundai, Ford, Toyota, Mercedes, and Infiniti all use Atkinson cycle engines. Briefly, the Atkinson cycle changes how the fuel-air mix flows into and out of the combustion chamber. Atkinson cycle engines are more efficient, but make less power per cubic inch or cubic centimeter. This loss of power is easily replaced by the electric motor and batteries.

Hyundai uses a 2.4-liter Atkinson cycle engine that, alone, is rated at 166 horsepower and 154 pound feet of torque which would make it a very wimpy performer. Fortunately, a 220 Volt, 5.3 Ampere hour 72 cell lithium polymer battery sends its power to a 30 kW (40.8 hp) e-motor that adds over 150 foot-pounds of torque to the transmission. You can’t just add the figures, but combined they make a very sporting powertrain.

Hyundai says that, compared to conventional nickel cadmium batteries like those used in Prius or Fusion for instance, their li-ion battery is 25% lighter and 44% smaller, and uses flat rectangular batteries called prismatic cells instead of familiar cylindrical cells. The battery is conditioned—heated and cooled—with air; some li-ion automotive batteries will be liquid cooled. Hyundai’s battery, produced by LG Chemical, is projected to last for over 450,000 km (about 280,000 miles) and offers a class-leading warranty of 10 years/ 100,000 miles. In comparison both Ford and Toyota continue with a 5 year/60,000 mile powertrain warranty.

This high-tech blather almost obscures our most important discovery, the difference you can really feel is the Sonata Hybrid’s conventional automatic transmission. While other brands use CVT-type transmissions which produce distinctive and often unpleasant rubber-band feelings during acceleration, in contrast, Sonata’s standard 6-speed renders a familiar driving experience, one that inspires confidence in the seat of your trousers.

One reason for using a conventional transmission that has nothing to do with efficiency, economy of scale, reuse of intellectual property and other really important stuff is that Hyundai’s US president John Krafcik has an aversion to the sense or feel of CVT transmissions. He says a 6-speed automatic can better manage engine speeds on the highway. We totally agree after driving this hybrid “briskly.” In our opinion, and Krafcik’s, a standard transmission gives a much better feel to the whole powertrain from the engine to the rear rubber.

The 2.4-liter engine revs authoritatively and we do not miss the shrill rubber band feeling produced by CVTs. Our driving style was one of total disregard for fuel-sipping “hypermileing” techniques and we achieved over 36 mpg while having fuel-frugal fun.

Others who donned the hypermile hair shirt of sluggish acceleration, coasting, no air conditioning and other dire techniques soared over our performance and attained over 50 miles per gallon, 57.7 to be precise. They had the championship, we had fun.

During our fast and fun discovery one additional fact stood out. In comparison to the sportier Sonata 2.0T, the Hybrid rides softer. El Presidente Krafcik tells us that, for some reason there is consumer connection between hybrid automobile and a softer riding chassis. We confirmed the slightly softer springs and damper settings with chassis engineers; it wasn’t a sensory mistake. For most, probably over 90% of the potential buyers, this chassis just fine. Only road warriors (we fancy ourselves such) might disagree. Then again, had we tested this car on harsh mid-Michigan roads the softer tuning might have been a benediction. We’ll share that when next we test the Sonata Hybrid.

What is my bottom line? Sonata Hybrid only adds more cachet to this growing brand with its distinctive styling and fresh approach to how a hybrid can be created. We think that Hyundai's plan to create hybrids from off the shelf components, using standard engines, transmissions, and batteries that can shrink or grow according to necessity makes perfect economic sense. In this scenario, only the e-motor might need to be re-engineered. Or, smarter is always better.

TOTAL KNOWLEDGE: Hyundai Buyers Guide