Honda says that the 2012 Civic Hybrid is the most fuel-efficient sedan (i.e. not a hatchback) on U.S. roads.

The all-new, ninth-generation 2012 Honda Civic Hybrid, using a lithium ion battery for the first time, increases its average EPA fuel economy rating from 41 mpg to 44 mpg. The new model is rated at 44 in both city and highway driving.

The improvement in fuel economy solidifies the Civic Hybrid’s second-place position for fuel economy among cars that don’t plug into the grid. The 44-mpg average moves the Civic slightly closer to the Prius’s 50-mpg level, and edges out the 42-mpg Lexus CT 200h. Honda makes the claim that the Civic Hybrid becomes the most fuel-efficient sedan – meaning it’s not a hatchback – on U.S. roads.

Like other new Civic models – there are now five different versions, including the HF high fuel-efficiency non-hybrid model – the 2012 Civic Hybrid gains a reworked exterior, a redesigned interior and new features.

The Powertrain

The 2012 Civic Hybrid employs the fifth generation hybrid powertrain system that Honda calls Integrated Motor Assist (IMA). It’s a descriptive moniker in that a thin, pancake-type electric motor/generator is “integrated” between the engine and transmission and only “assists” the gasoline engine. This compares to hybrid systems from Ford and Toyota where the electric motor can assist the gas engine plus, propel the vehicle on electric power alone. In certain instances, the Civic Hybrid engine does cut off fuel and the car operates briefly on electric power only, but the engine’s parts still move. Like other hybrid vehicles, the Civic shuts off the engine when the car comes to a stop, and then fires up again when it’s time to go.

In addition to the shift to lithium-ion batteries, the 2012 Civic Hybrid gains a larger gasoline engine, a 1.5-liter four-cylinder in place of a 1.3-liter. Combined gasoline and electric horsepower is unchanged at 110 and torque is up a nominal four pounds-feet, to 127. Yuuji Fujiki, chief engineer for Honda’s IMA hybrid system, explained that the larger displacement allows the engine to run at lower RPMs, which in turn allows for more frequent use of the electric motor and produces a quieter ride.

Fujiki said every aspect of the hybrid system’s design was tweaked for optimal efficiency – such as the motor that increases output from 15 kW to 20 kW, uses more coils and widely spaced magnets, and employs plastic spacers to better manage temperature. The motor provides up to 23 horsepower, a three horsepower gain over the previous motor.

The 20-kW Li-ion battery is more powerful by 5 kW and 30 percent lighter than the previous generation’s nickel-metal hydride battery. The IMA system’s greater power and the battery’s 35 percent increase in efficiency allow the Civic Hybrid to operate more frequently on the electric motor’s power alone in certain low-speed cruising situations.

There’s a side benefit in going lithium: so the next generation of Civic Hybrid owners don’t go postal.

The Civic Hybrid is the only hybrid model for which we’ve seen numerous customer complaints about critical battery failures. Civic Hybrid owners have reported loss of power or outright pack failures, and have not been satisfied with the company’s fixes. The shift to lithium hopefully will put the issue in the rear view mirror.

Completing the IMA system is a continuously variable transmission (CVT). The CVT consists of a drive pulley and driven pulley that are linked by a steel belt, and operates sort of like a 10-speed bicycle. It combines the fuel economy of a high-gear ratio manual transmission, the performance of a low-gear manual with the smooth, stepless shifting of a conventional geared automatic transmission.

Exterior

Like the rest of the 2012 Civic line, the redesigned Civic Hybrid doesn’t have swoopy lines, sharp creases or a dramatic profile like some small cars that revamped their looks this year. Instead, the updated styling is a natural evolution of the outgoing model, a design that received rave reviews when introduced in 2006. Consumers will recognize the Civic’s raked windshield, wedge shape, wide stance and other styling features that do not dramatically depart from the 2011 model.

In front, there is a unique hybrid grille design with blue accents, and within the sleek headlight assemblies are blue bulb covers that provide additional distinction. Special five-spoke alloy wheels, a decklid spoiler and LED brake lights further differentiate the Civic Hybrid from other Civic models.

Interior

The new Civic Hybrid’s interior features a redesigned version of the previous-generation’s two-tier instrument layout, a design that places a digital speedometer in the top level above an analog tachometer. The upper tier is wider to fit a feature Honda calls the intelligent Multi-Information Display, or i-MID. This 5-inch screen right of the speedometer readout displays a wide variety of audio, trip, and fuel-economy data. It also contains a hybrid power-flow meter display. A new steering wheel includes thumb controls for the multitude of audio and i-MID functions.

In Honda tradition, switchgear lays easy to hand and seats are supportive. However, the Civic seems to be stuck in time in terms of cabin materials. Plastics are mediocre when compared to other new compact models and the “mouse fur” ceiling fabric is actually a step backward.

Exterior dimensions are unchanged from 2011, while wheelbase – the distance between the front and rear axles and a key measurement that affects interior volume – has shrunk by 1.2 inches. Yet Honda engineers somehow expanded cabin space by almost four cubic feet. Notable differences are some three inches of front and rear shoulder room and 1.6 inches of additional rear legroom. There’s also a wee bit more trunk space, thanks to the smaller battery pack, though the rear seat still doesn’t fold in the Civic Hybrid.

Standard equipment is on par with the gas-powered Civic’s top EX trim level. The Hybrid comes with: power windows; outside mirrors and locks with remote keyless entry; cruise control; automatic climate control; tilt-telescoping steering column; manual height adjustable driver’s seat: Bluetooth connectivity; and a 100-watt AM/FM/CD six-speaker sound system with USB, MP3 and WMA ports.

Honda equips every Civic with anti-lock brakes with brake-force distribution, electronic stability and traction control and a full complement of airbags, including curtain-style bags.

On The Road

The Civic Hybrid doesn’t stray too far from its gasoline cousins. The Civic’s ride and handling reputation of being among the very best in class continues. Tweaks to the all-independent suspension, the shorter wheelbase and a stiffer body provide a more refined ride comfort than the 2011 model while maintaining agile and responsive handling. Steering is nicely weighted and executes sharp cornering in an effortless manner.

Tough horsepower is the same, the larger displacement 1.5-liter four is more responsive than the previous 1.3-liter engine. While it won’t win any stoplight drags, once up to speed it’s a solid performer when merging onto freeways and passing.

Around town the Hybrid has a smooth, fairly well-damped ride and it’s easy-to-drive and easy-to-park. The highway ride is firm, controlled and pleasant, not harsh. Bumps and those pesky expansion joints have a negligible impact.

Two things set the Hybrid apart from the gas Civics. First, while improved, the regenerative brakes still have a jerky pedal feel that take time to get used to. Second, and again improved, when the gas engine restarts after shutting down temporarily at stops, the car shudders as it gets up to speed.

Hybrid cars are all about fuel economy and Honda challenged journalists attending the media preview for the 2012 Civic in Washington, DC. hybrid-crew.com, using hypermiling techniques, achieved the upper limit of what any driver should ever expect for fuel efficiency. On a 10-mile course of mostly country lanes and some highway driving, with four or five stoplights along the way we won the MPG Challenge, scoring 68.7 mpg.

Economics

For 2012, the base Civic Hybrid has a suggested retail price of $24,050, up $100 from 2011. A leather-trimmed interior package that includes heated front seats adds $1,200. Combine the leather with a navigation package and the sticker price is $27,150. In comparison, the Toyota Prius Three, the most popular 2011 model with fuel economy rated at 50 miles per gallon in combined city/highway driving, starts at $24,520 and includes satellite radio.

In the past, Prius buyers usually spent at least a couple thousand more dollars to buy Toyota’s celebrity hybrid than those who drove off with a Civic, but that has changed. Not only has the price gap narrowed, the Prius is a larger car and it’s hatchback style allows the rear seats to fold forward, enlarging the cargo space from 21.6 cubic feet to nearly 40 cubic feet.

Even though the price comparison between the Civic Hybrid and Toyota Prius tips the scale toward the Prius with its better fuel economy, the Civic Hybrid will satisfy shoppers who value the Honda Civic for its reliability and contemporary look, but really want a hybrid. And, if the Prius design is not your cup of tea, and you can live with a compact rather than a mid-size sedan, then the 2012 Honda Civic Hybrid is worth a strong consideration.

Prices are Manufacturer Suggested Retail Price (MSRP) at time of publication and do not include destination charges, taxes or licensing.