The vehicle as an electricity generator.

The VISION EQXX technology programme has already provided a clear preview of efficiency in the forthcoming electric and digital age. However, the journey into the future continues: Mercedes-Benz is constantly researching new technologies to shape the mobility of tomorrow. The company is providing exclusive insights into ongoing research activities aimed at automotive progress far beyond the current period of transformation – innovations for a completely new era of mobility. This includes the development of ground-breaking technologies for a better quality of life and road safety, for more climate protection and resource conservation and for more digital experiences that are hyper-personalised and extend far beyond the vehicle.

At 5 micrometres, they are significantly thinner than a human hair, weigh just 50 grams per square metre and are packed full of energy. Mercedes-Benz is researching a new type of solar modules that could be seamlessly applied to the bodywork of electric vehicles – similar to a wafer-thin layer of paste. The active photovoltaic surface can be applied to any substrate. The solar cells have a high efficiency of 20 per cent. An area of 11 square metres (equivalent to the surface of a mid-size SUV) could produce energy for up to 12,000 kilometres a year under ideal conditions¹. The energy generated by the solar cells is used for driving or fed directly into the high-voltage battery. The photovoltaic system is permanently active and also generates energy when the vehicle is switched off. In future, this could be a highly effective solution for increased electric range and fewer charging stops.

The yield depends on levels of shade, the intensity of the sun and geographical location. By way of example: Statistically, Mercedes-Benz drivers in Stuttgart, Germany cover an average of 52 kilometres a day. Around 62 per cent of this distance would be covered using solar energy. In Los Angeles, there is even a surplus of energy from solar radiation. The customer could cover 100 per cent of their driving distance on average by solar energy. The surplus achieved could be fed directly into the home network via bidirectional charging.

The solar paint not only has a high level of efficiency. It contains no rare earths and no silicon, only non-toxic and readily available raw materials. It is easy to recycle and considerably cheaper to produce than conventional solar modules. The Mercedes-Benz research department is currently working to enable use of the new solar paint on all exterior vehicle surfaces – regardless of their shape and angle.

As electric vehicles brake primarily through recuperation, Mercedes-Benz is taking a pioneering new direction in the development of mechanical brakes. The innovative, more sustainable brake currently under research no longer occupies its conventional location inside the wheel. Instead, it is integrated into the electric drive unit at the front or rear axle. It occupies very little space – and according to the latest research, is subject to minimal wear, doesn’t rust and is virtually maintenance-free. This would make it very durable and reliable. In addition, there would be no particulate emissions into the atmosphere. Braking noise and brake cleaning could also become a thing of the past. The braking effect is easy to control and does not fade even under heavy loads.

The innovative design also enables a significantly lighter wheel/tyre combination and therefore lower unsprung mass, which, in turn, improves ride characteristics. In addition, it would facilitate fully closed rims for optimised aerodynamics, as openings for brake cooling would no longer be required.

Mercedes-Benz is also striving for a paradigm shift in the use of a new generation of power electronics technologies in electric vehicles. In future, a programmable micro-converter could go beyond the limits of current electrical inverter systems and revolutionise existing high-voltage architectures. The basis for this is the integration of these micro-converters directly at battery-cell level, which could enable individual control of battery-cell pairs as well as communication between cells.

To realise this, a power converter consisting of several micro-converters is connected directly to any number of cell pairs. This power converter makes it possible to regulate cells individually and also the level of output voltage. Current research results show it is possible to provide a constant HV output of 800 volts, regardless of the state of charge (SoC) and the state of health (SoH) of the individual cells. The output voltage of this vehicle battery is no longer dependent on the number of cells connected in series. The number is determined purely by the desired performance and capacity class. This technological approach could also increase electric range and optimise energy flow for bidirectional charging. Furthermore, it could deliver new levels of freedoms in the modularisation of electric drives.

The programmable micro-converters could reduce the production variants of electrical components and could also be easily reprogrammed for the latest updates. As standardised parts, they could thus lower the use of resources. They have the potential for use in many future Mercedes-Benz electric models.

The new technology has the potential to enable integration of several power electronics functions into the HV battery. This means various power components could be realised by the HV battery itself, achieving a whole new level of integration in electric vehicles. The significantly improved use of space as well as a reduction in the number of variants would open up entirely new freedoms in the layout and design of electric vehicles.

¹ Based on the light incidence in Stuttgart.