BMW last week revealed details of the powertrain in its i Hydrogen Next crossover, whose hydrogen fuel cell propulsion system could become another pillar of the automaker's drivetrain portfolio.
The i Hydrogen Next is based on the X5 midsize crossover and could go into small series production in 2022. The automaker said it will continue to cooperate with Toyota Motor Corp. to roll out the technology in the second half of the decade, depending on market conditions.
"Hydrogen fuel cell propulsion can in the longer term become a fourth pillar in our drivetrain portfolio, in particular for the upper end of our X family," BMW's outgoing R&D chief, Klaus Fröhlich, said in a statement last week, referring to the brand's crossover lineup.
BMW said the fuel cell stack of the i Hydrogen Next converts the 6 kilograms of stored compressed hydrogen gas fed from two 700-bar tanks into an output of 168 hp, with water vapor as a waste product.
There is also an additional battery housed above the electric motor, helping to provide more performance, for example, when the vehicle is accelerating or overtaking other vehicles.
An electric converter beneath the fuel cell stack continuously adjusts voltage to the drivetrain and the battery. The battery is fed by recuperated brake energy and the fuel cell. Cumulative system output amounts to 368 hp.
Since 2015, BMW's research arm has been testing a small fleet of prototype 5 Series GT hydrogen fuel cell vehicles powered by a jointly developed drive system with a Toyota fuel cell stack.
When the BMW i Hydrogen Next was first shown at the Frankfurt auto show in September, CEO Oliver Zipse said the company would be ready to launch the vehicles when the market demands it.
In March, Fröhlich emphasized that fuel cell vehicles were still a long way off from commercialization, however. "Hydrogen fuel cell technology is roughly at the point where electromobility was 10 years ago."
For now, infrastructure is not sufficient, the price remains at least twice as high as an equivalent battery-electric vehicle, and supplies of the gas are not sustainably produced.
Although hydrogen is one of Earth's most abundant elements, it rarely exists as a gas. Industrial scale production derives from refineries that crack apart hydrocarbon molecules found in fossil fuels. The only green method requires an enormous amount of electricity, as it entails splitting water into its constituent atoms through electrolysis, a process only economically feasible when there is sufficient surplus renewable power, such as wind or solar.
