by Jim Kerr
photos by Grant Yoxon
Third Generation Ford Focus FCV in the Lab at Ford Science and Research Centre, Dearborn, Michigan.
Take an economical, high sales volume vehicle, and make it produce the lowest emissions possible. That’s the way to make the biggest impact in reducing total vehicle emissions, and auto manufacturers have been looking at many strategies to accomplish this. Ford recently displayed their latest design, the Ford Focus Hydrogen Fuel Cell Electric Vehicle. Hidden beneath the body of an amazingly stock looking Focus sedan sits a quiet, efficient, compact fuel cell powerplant that produces Zero emissions.
Ford calls it the THINK fuel cell system. Think has been the name associated with Ford’s line up of electric vehicles, and the fuel cell Focus is essentially an electric car with the advantage of having its own generator on board. That generator is a Ballard Mark 902 fuel cell stack.
The Ballard 902 Fuel cell is a Proton Exchange Membrane (PEM) type. Hydrogen from the fuel tank flows onto one electrode in the stack. The electrode is coated with a catalyst that separates the hydrogen into protons and electrons. The electrons are used for power, while the protons pass through a polymer membrane to another electrode that combines oxygen with the hydrogen protons to produce water vapour. Water is the only emissions.
Fuel cells have been around for a long time, but the automotive industry has only been seriously involved for a little over a decade. Ford first got involved in the early 1990’s and their first significant fuel cell was produced in 1993. In 1997, Ford scientists built the P2000 fuel cell car, which still holds the record of travelling 1391 miles in a 24 hour period. Since that time, a second generation Focus fuel cell car has been used for research, and the current Focus is called a Generation 3 design. The big difference between Generation 2 and Generation 3 is in the packaging. The Generation 2 Focus used individual hand built components, while the Generation 3 Focus uses a modular integrated design that looks production ready.
And this vehicle is closer to production than one might think. Just last January, the engineers had the modular component designs. In March, they showed a completed car using the modular concept, and by the end of this year, they will have five vehicles operating on California roads. All this is leading up to a 2004 production program.
The Generation 3 Focus fuel cell vehicle is also a hybrid vehicle. Rather than getting all its power directly from the fuel cell, it also uses a battery pack. The battery pack is a module containing 180 rechargeable “D” cell batteries (the production capabilities for this size already exist) producing a nominal 315 volts. Regenerative braking is used to help recharge the battery pack during deceleration.
Fuel cells don’t accelerate as fast as battery powered vehicles, so using a hybrid design enables reasonable performance in a Zero emissions vehicle. Ford specs list the Focus’s performance as 260 to 320 km driving range, and a top speed of 128+ kph. The powertrain produces 87 horsepower and an impressive 170 ft-lb. torque.
D-cell battery pack module. Click image to enlarge
There are still lots of issues to deal with regarding hydrogen-powered vehicles. Customers are not willing to give up anything to drive zero emissions vehicles, so the technology has to be transparent. Safety is critical with 5000 psi pressurised hydrogen on board, but Ford fuel tank designs have included the shutoff valve and regulator inside the tank. External pressure is regulated to only 200 psi.
Refuelling is still a problem. Why have filling stations if there are no hydrogen cars, and how can you drive the cars without filling stations. Ford has been working with Stuart Energy Systems, a leader in hydrogen refuelling station equipment, to promote a refuelling infrastructure.
Finally, there is the cost of producing hydrogen fuel. It takes about 50 to 60 kilowatt hours of electricity to produce 1 1/2 kg. Hydrogen, and 1 kg hydrogen is equal to about 4 litres of gasoline. The current estimated cost equivalent to produce hydrogen fuel is about $3.00 US per gallon, so it is still an expensive fuel unless cheaper sources of electricity or more efficient methods of producing it are found.
Fuel cell cars will likely not dominate our transportation needs, but there will definitely be a place for them in our future. It looks like Ford is planning to be there to fill our needs.