Last week Ford unveiled an experimental version of the Edge CUV powered by the HySeries drive-train that they first showed in the Airstream concept at the recent North American International Auto Show. This is a plug-in series hybrid setup that uses a hydrogen fuel cell as an auxiliary power unit to charge the battery on the go. There is a hydrogen storage tank mounted longitudinally down the center of the vehicle. Under the driver side of the floor lies a lithium ion battery back with a peak output of 130kW. On the opposite side is a Ballard fuel cell stack that generates electricity to charge the battery.
This Edge drives all four wheels via a pair of 65kW electric motors mounted at each axle. Unlike the previous Focus FCV which was a parallel hybrid and used the fuel cell as the primary power source to the motor, the Edge drives the motors from the battery. The previous configuration sent power directly from the fuel cell to the motor and used a NiMH battery to provide extra power for acceleration. As a result a larger fuel cell was required and it had to work harder. Since the LiIon battery can provide power on demand more quickly, it becomes the primary power source, and a smaller fuel cell works mainly to keep the battery charged when it gets low. The result is that a smaller, less expensive stack can be used, because it doesn't need the peak power output to keep the battery topped up.
Continue reading after the jump
A direct comparison of the Edge specs with those of the Chevy Volt concept, at first glance, appears to show the Edge lacking. However, this isn't an entirely fair comparison. The Edge has a nominal range of approximately 225 miles based on a charged battery and a full 4.5kg hydrogen tank, although Ford says that they have seen a range as much as 400 miles in testing. By comparison, the Volt is claimed to have a range of up to 640 miles. Similarly, the Edge has a range of 25 miles on battery power, while the Volt can go 40 miles. The Edge uses a pair of 65kW motors for a total of 130kW, the same output as the single motor on the Volt. The batteries in both vehicles have a peak output of 130kW as well.
The Edge battery itself, is a 45 A-hr cylindrical lithium ion cell, although the supplier has not been disclosed. According to Ford they have built additional battery packs with different technologies than the one currently installed and they are currently benchmarking them. The new smaller fuel cell stack is designed to start and run at temperatures down to -15C and is being tested down to -25C. The cell has also been "heat integrated" with all the components in a single package. This helps to improve the staying time when parked outside in cold temperatures.
So why the difference in range? The Volt is about the same size as a Chevy Cobalt and weighs in at about 3,100 lbs. The Edge is a substantially larger cross-over utility vehicle and the standard production AWD model weighs in at almost 4,300 lbs, while this hybrid version comes in at almost 5,400 lbs. When you mix the same power and battery capacity with almost seventy-five percent more mass, it's definitely going to cut into your range. Unfortunately, even with all of the technological advances made in the last century, Newton's laws of motion still apply. Right now Ford is working on second HySeries Edge, that will be focused on reducing the weight and improving the fuel consumption and range.
The vehicle uses the standard Edge front suspension, but a new rear sub-frame was fabricated to support the rear electric motor. The Edge does have regenerative braking to help improve the range. At the moment, this is just a technology demonstrator, to help Ford evaluate the practicality of the HySeries drive system. Based on the data Ford collects with the first two vehicles, they will decide whether to proceed with a larger test fleet.
Like the GM E-Flex platform that underpins the Volt, Ford intends for the HySeries platform to be flexible, allowing for alternative power-units to be used in place of the fuel cell. They say it can use an internal combustion engine, although the packaging of this vehicle seems less conducive to this alternative then the E-Flex setup. The use of a higher pressure hydrogen tank can increase the fuel cell range from 200 to more than 300 miles. The battery can be charged by plugging the vehicle into either a 110V or 220V outlet.
Cue Press Release...
HySERIES DRIVE PLUG-IN HYBRID POWERTRAIN
How It Works
The Ford Edge with HySeries Drive TMis a battery powered plug-in hybrid with a fuel cell that operates as an on-board charger. The vehicle operates in "battery only" mode for the first 25 miles at speeds up to 85 miles per hour. When the battery is depleted to approximately 40%, the fuel cell auxiliary power unit (APU) automatically starts up and recharges the battery, giving the vehicle an additional 200 miles of range. The range can be increased to more than 300 miles with a high pressure tank. The fuel cell's sole function is to recharge the vehicle's lithium ion battery pack as needed, allowing this break-through technology to work like a portable generator, instead of an engine, as had been the case in previous fuel cell powered vehicles.
The vehicle is equipped with electrical charging and hydrogen fueling ports on the driver side of the vehicle, in the front and rear. The high voltage battery can be conveniently charged overnight from home or at work on either a 110 or 220 volt outlet. The hydrogen fuel tank holds 4.5 kg of hydrogen and takes about five minutes to fill. This is a zero emissions vehicle and when the fuel cell is operating, only water vapour is emitted through the exhaust system. This advanced powertrain delivers an EPA combined city / highway fuel economy equivalent of 41 miles per gallon.
The architecture is fully flexible and adaptable to other power sources, which allows for flexibility during fuel cell development and hydrogen infrastructure expansion. The benefit of this design is that it allows the flexibility to swap out the fuel cell for a small combustion engine to recharge the lithium ion battery pack.
65kW Electric Drive
Fuel Cell (APU)
130kW (336 Volt)
65kW Electric Drive
Hydrogen Port • Overnight Home Recharging (110 / 220 VAC)
• 25 Mile Range on Li-Ion Battery
• Zero Emission Hydrogen Fuel Cell APU
• 225 Mile Combined Range with Battery / Fuel Cell
• Uncompromised Interior Package
• Electric AWD
Fuel Cell: 35kW Fuel Cell
Motor: 130 kW Dual Electric Drives
Hybrid Battery: 130 kW Li-Ion
Hydrogen Storage: 350 bar, 4.5kg H2
Seating: 5 Passenger
Range: 225 mi
EPA Fuel Economy: 41mpg