Once, a couple of decades ago, when electric mobility seemed a distant dream, Mercedes-brought to light the electric-powered 190E sedan at the Hanover Fair in May 1990. Raw in design, no fancy touch of technology and far from sophistication, the German automaker exhibited a model 190 (W 201) converted to electric drive.
“In this way, the Mercedes 190, which in terms of length and weight comes closest to the requirements of an electric vehicle, is an ideal battery test vehicle. The main objective is to assess the functional suitability of all the components in realistic situations with all the vibrations, accelerations and temperature fluctuations experienced in everyday operation,” explained the brochure issued at the time.
Unlike the current state-of-the-art Mercedes EQ — an epitome of non-conventional luxury, the electric 190s went through the grind of different drive configurations and battery systems trails. The energy storage devices tested were mainly sodium-nickel chloride or sodium-sulphur high-energy batteries which had a significantly higher energy density than classic lead batteries. However, the working temperature of both systems was around 300 degrees Celsius.
Within a year’s time, Mercedes-Benz made significant inroads, bringing a more advanced vehicle at the Geneva Motor Show in 1991. The car is still a fully-fledged five-seater with almost unchanged effective space and with tried-and-tested Mercedes-Benz safety features, the press kit explained.
Each of the rear wheels of the vehicle presented in Geneva was powered by its own DC motor energised by permanent magnets with a peak power of 22 hp each, so the total power output was 44 hp. Energy was supplied by a sodium-nickel chloride battery, and regenerative braking returned energy to the power pack during braking actions. A particular advantage of the concept was the elimination of weight-intensive mechanical components, so the additional weight compared to a series-production vehicle with a combustion engine was only 200 kilograms.
The pioneering 190s were driven by test participants every day, who were from various walks of life, on the island of Rügen. There were hardly any problems – the W 201 cars went about their work completely inconspicuously and reliably. One of the vehicles was used particularly intensively and achieved a peak usage rate of around 100,000 kilometres in one year.
“The results provide new insights into battery service life, the number of possible discharge and charge cycles, range, energy consumption and reliability,” summarised the Mercedes-Benz brochure. In the following years Mercedes-Benz applied the electric drive concept to other passenger cars.
The question remains as to why electric vehicles are only now becoming established and why they did not take off based on the projects of that time. Battery service life, range, recycling, charging infrastructure and vehicle price are quoted as just some of the keywords in a Mercedes-Benz press release from spring 1991 as challenges faced by e-mobility on the way to series production. Many of the answers to these questions have only become available today, only with others joining the picture.