This summer car manufacturer BMW presented a new vehicle driven by a fuel cell. In Miramar in the south of France, the Bavarian company revealed their new BMW 5 Series Gran Turismo (GT) on the first of July 2015. The car is a showcase vehicle, which was developed in cooperation with Toyota and is planned for mass production by 2020.
Based on the already available GT model, it is the first vehicle from Munich’s car manufacturer that generates engine power only by the use of a fuel cell. Until 2006, BMW had focused almost entirely on H2 combustion engines and equipped eight generations of cars with an Otto engine and a liquid hydrogen tank, before halting development work altogether. In 2013, BMW and Toyota announced their cooperation, during which the Bavarian car manufacturer has benefitted from Toyota’s experiences with fuel-cells, and Toyota had the favor returned by BMW sharing their diesel expertise with the Japanese producer.
“We will continue to explore all avenues of development, but the combination of fuel cell and hydrogen seems to be another possible drive system from around 2020 on. […] The fuel cell is a key part of our strategy for the future,” BMW’s Head of Development, Klaus Fröhlich, explained. The target was to design a fuel cell as compact as an internal combustion engine, so that the same chassis could be used for both fossil-fuel and electric cars. Additionally, high-pressure carbon fiber tanks should be shaped similar to battery units, in order to allow replacing one by the other.
When asked by H2-international, a company spokesperson said: “The fuel cell incorporated into the BMW 5 Series Gran Turismo is a result of our cooperation with Toyota, and it is basically the same one that is being used in Toyota’s Mirai. Some peripheral units share the same design too. However, the car itself was developed by BMW on its own. For instance, the powertrain is based on BMW-i technology.”
The gaseous hydrogen is stored between front and rear axle either in a 700-bar tank or a two-meter long, 350-bar tunnel tank patented by the BMW Group. Ten showcase vehicles were built to allow testing both storage technologies, the 700 bar version as well as the cryo-pressure tank one. BMW said that the same amount of resources were going into developing the two technologies further.
In the second case, the cryogenic version, the container made of aluminum and carbon fiber weighs 160 kg. Its heat insulation guarantees that the tank’s interior remains at between -210 to -230°C (over several weeks). Car refueling uses the new cryogenic pressure technology (CCH2), which was first tested at the new public H2 filling station in Munich. The 7.1 kg of H2 gas stored this way (at a capacity of 237 kWh) enables a range of 500 km. But if requested, the cryogenic pressure tank can also be filled at 700 bar. The container will then only hold 2.1 kg, which will obviously result in a lower range.
“As it is BMW‘s belief that the ideal use of hydrogen fuel-cell technology will be for medium to large cars – meaning usually long-range vehicles – the typical space requirement to install the technology will be today’s tunnel version.“
The H2 5 Series is driven by an electric engine with a power of 180 kW. As an addition to the fuel cell, electricity is supplied by a high-voltage battery for intermittent storage (1 kWh). In contrast to common electric cars, this sports vehicle offers a two-gear automatic, which shifts once at around 80 to 90 km/h. This technology could be the foundation for a hydrogen-powered BMW race car participation in the 24 Hours of Le Mans from 2018 on.
BMW did not want to confirm any rumors circulating of a fuel-cell i5 complementing BMW’s current model offerings of i3 and i8. Instead, the company made the following statement: “The aim of our cooperation with Toyota is to have components available for future hydrogen fuel-cell vehicles and ready for mass production by 2020.” Asked about the market entry of future H2 cars, Fröhlich recently told the Süddeutsche Zeitung: “I think 2025 is more of a realistic time frame.”
Besides the 5 Series, the Bavarian engineers also equipped an i8 with a fuel cell for testing. “The matte black prototype was developed by BMW on its own until 2012. Thus, it was designed and built before the cooperation with Toyota and was based on other technologies. The car is no longer in use today.”