Now what? Now people have to buy them.
For all the game-changing glow around the Ford Fusion Hybrid, it's actually a fairly conservative and programmatic approach to gas-electric propulsion. The system is an evolution of the hybrid system in the Ford Escape. The battery is nickel-metal hydride, not lithium (lithium chemistry batteries are lighter and more energy-dense, but they are also expensive and finicky, which is to say, flammable).
The nickel battery will please many in the green-car movement who argue that the search for the perfect battery -- a la the Chevy Volt -- has only delayed development of the good. (Edmund Burke said the worst thing a man can do is do nothing because he can do only a little.)
The Sanyo-supplied battery pack -- 270 volts and 1.4 kWh, if that helps -- is 30% smaller in volume and 23% lighter than the one in the Escape. The smaller battery is easier to cool, requiring only cabin air ducted from underneath the back seat.
The battery supplies enough glowing ponies to propel the car to speeds up to 47 mph on all-electric power. This is key to the car's in-city mileage. On my 50-mile drive, I was able to feather-foot the throttle enough to accelerate to commuting speeds without waking the gas engine. When I needed to accelerate faster, I could dip in to the engine horsepower briefly to overcome inertia, then maintain momentum with the electric motor. At one stage I was getting 63 mpg.
To make a full-size car go fast on electric power alone, you need a boatload of voltage. But high-voltage systems involve increased impedance and heat losses, which is wasted energy. To unknot this problem, the Fusion uses a variable-voltage converter that temporarily steps up system voltage during peak demand or hard braking, when the battery is forcefully recharged.
This is actually one of two high-tech converters on board: The second system provides juice to an array of high-voltage systems such as steering, air-conditioning and brakes.
There's a lot of other arcane technology that goes into a car, like reams of software code that allow all the various components to talk sweetly to one another. But perhaps the most valuable bit of software is the wetware, the stuff between the driver's ears. To that end, the Fusion Hybrid uses a delightful, LCD instrument cluster with modules that coach drivers on how to save fuel. In one panel, the more lightly you drive, the more leaves that grow on a set of animated vines. You can go from lead-footed, gas-bingeing knucklehead (like me) to abstemious hyper-miler in a matter of minutes. Brilliant.
