Fuel cell 'B' faces deep freeze

A Mercedes-Benz B-Class driven by electric motors powered from a fuel cell has just completed cold weather testing in Sweden. Engineers had already worked out a theoretical means of operating the fuel cell vehicle from a cold start of -25 degrees Celsius, but the Swedish test program confirmed that the theory would work in practice.

Fuel cells don't cope all that well with extremes of weather, so the successful conclusion of testing north of the Arctic Circle is big news. 

For viable cold-starting, MB engineers developed an electric turbocharger to supply air and a humidification and demisting system specific to the fuel cell B-Class.

The B-Class will, in fact, be the first MB model to go into series production with fuel cell power, early in 2010. In this application, the fuel cell componentry will be more compact than pilot fuel cell vehicles developed from the smaller A-Class. The fuel cell stack is 40 per cent smaller, but provides 30 per cent more output for 16 per cent less consumption (hydrogen).

With the changes introduced in this new experimental system, the B-Class develops 100kW of drive power from the electric motor and 320Nm of torque, despite producing virtually zero emissions. Consumption is as low as 2.9L/100km.

The cold weather testing program in Sweden also concentrated on roadholding and ESP parameters for the fuel cell B-Class and the engineers tuned the ESP to work effectively with the electric motor, with its different speed governing characteristics.

They claim that the experimental car offers cornering ability exceeding that of a car fitted with a 2.0-litre combustion engine.

"The results of the winter tests proved that we are on the right track with this innovative drive concept and have taken another important step on the road to reaching production standard. As with the standard test programs for conventional vehicles, we will be subjecting the B-Class F-CELL to further rigorous testing over the next few months," said Dr. Thomas Weber, Daimler AG board member with responsibility for Research and Development at Mercedes Benz Cars.

To comment on this article click here