Charging ahead with fuel cells . . .

FirstDrive/Mercedes fuel cell F600 concept: Mercedes's A-Class concept is a quality contender in the race to get a fuel-cell…

FirstDrive/Mercedes fuel cell F600 concept:Mercedes's A-Class concept is a quality contender in the race to get a fuel-cell car onto the forecourts, writes Joaquim Olivera, if it manages to keep the car's price down

Amid the skyscrapers of Shanghai, Michelin decided to give its view of the future of motoring in front of some 3,000 interested spectators.

This was the scene of the ninth Michelin Bibendum challenge, a three-day demonstration programme where not too futuristic technologies are put on display, using cut-away models, explanatory video clips, multimedia presentations and even specialised engineers in each stand.

Star billing at this year's show went to the Mercedes F600 Hygenius.

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First unveiled at the 2005 Tokyo Motor Show, this may be somewhat of a dated concept, but its technical solutions are still cutting edge and have yet to make it into production, though they are pencilled in to appear in a B-Class fuel cell vehicle by 2010. Mercedes aims to be the first manufacturer to offer a production fuel-cell model to the market, though it will come under stiff opposition from rivals such as Honda, which already has trials underway, and Mazda, which is testing fuel-cell versions of its car on a major Norwegian highway from next year.

However, Mercedes has already completed extensive testing of its fuel-cell technology. An A-Class fuel-cell test vehicle, which has completed almost 3.78 million km during a five-year-long-term test has already provided the German brand with invaluable information.

This was our chance to drive the B-Class fuel-cell model, or the F600 concept as Mercedes continues to call it.

So enough of the technology briefing: what's this car like to drive? Well, aside from the great interior space and visibility, there are some striking features destined to improve comfort.

The greatest of these - and the most striking feature of driving fuel-cell vehicles - is the silence.

As ever when driving a concept, one has to be forgiving. Everything is handmade and the overall assembly quality is not a concern. In this case, the interior panels looked quite smooth and compatible, but some of the main switches and knobs were not functioning. Still, this car is very far advanced from the initial test models of the early 1990s.

For a start, the fuel-cell stack now fits underneath the cabin and is 40 per cent smaller than before. Another feature is its ability to start in freezing temperatures (down to minus 25 Celsius), courtesy of a new humidifier and plastic film which gets rid of liquid water left in the stacks when the driver switches it off. Freezing was a problem for early fuel cell vehicles.

In this latest version, the maximum output is now 115bhp and the top speed hits 170km/h, with an equivalent consumption of an amazingly low 2.9 litres/100km and a 400km range.

This impressive fuel efficiency is due to the intelligent management system which has many similarities with the way hybrid power (as in the Prius) works: during normal acceleration, for instance, the electric motor is directly fed by the energy supplied by the fuel cell (up to 90 bhp). Any additional energy is used to recharge the high-voltage battery. Moreover, when starting and overtaking (ie when there is a sudden need for more power), the battery comes into play and both sources raise the maximum output to 115bhp.

Alternatively, when manoeuvring at low speeds (as in parking), the battery works as the sole energy provider, generating up to 75bhp (the new lithium-ion device doubles the former nickel metal-hydride output). Finally, when braking, the motor automatically changes functions and acts as a battery recharger.

One point to note in all the earlier figures is the range: this larger F600 can now travel double the distance of the earlier A-Class fuel cell test vehicle before refuelling. The secret here is down to the newly developed tanks, which can sustain the four kilos of hydrogen at 700 bar pressure, twice as much as before.

Mercedes accepts that sales of this fuel-cell vehicle in 2010 will be limited, if for no other reason than fuel-supply issues. The other limiting factor may well be price: BMW has several hydrogen/petrol 7-Series cars on the road, but they are only for lease because the sales price is a seven-figure sum. Mercedes engineers and marketing personnel are well aware that a fuel cell B-Class will most likely be a flop if it goes any higher than an additional 20 per cent above the regular B-Class retail price at present.

Then there is reliability. This vehicle still faces a major technical glitch: the system's durability is currently 2,000 hours or 100,000km (peaking at 3,000 hours/150,000km under controlled conditions). Mercedes knows that in order to match a standard vehicle's longevity it will need to improve to around 4,000 hours/200,000km, before a major overhaul.

Next up are the safety concerns. While fuel-cell cars will undoubtedly carry the requisite number of airbags and the like, some questions have been asked about the batteries.

Toyota's recent announcement that its future hybrids and fuel cells will not feature lithium-ion batteries raised some eyebrows within fuel-cell-development circles.

Mercedes's Rosario Berretta, manager of the fuel-cell fleet said: "We have conducted all the necessary safety tests and there is no reason to postpone the use of lithium-ion batteries. Certainly we would not introduce it had we any kind of question mark pending on this subject."

Time is fast creeping up on Mercedes, but for all the issues that need to be addressed, there is an air of confidence within the brand that it will indeed have a fuel-cell production car ready for forecourts in 2010. The race is on to sell the first fuel-cell car to the general public and Mercedes is certainly in the running.