It will take a range of solutions to achieve the carbon-neutral operations that many carmakers, including BMW, have pledged to achieve by the middle of this century. Battery electric vehicles (BEVs) will carry the bulk of the clean energy charge going forward, but the German manufacturer is not alone in believing that hydrogen-powered fuel cell vehicles (FCVs) will be an essential part of the mix. Honda, Hyundai and Toyota also share that sentiment with their current and upcoming FCV models. After driving a new iX5 FCV prototype in Belgium, we came away thinking that BMW might be on to something, even if that something probably won’t materialize for another decade or two.
Fewer than 100 iX5s will be built this year as part of a demonstration fleet for various regulatory bodies and marketing efforts. Only a small handful will make it to the United States, where – unlike central Europe and parts of Asia – hydrogen infrastructure is virtually non-existent outside of California. Production involves shipping an X5 from its Spartanburg, South Carolina, birthplace to the BMW Research and Innovation Center in Munich. There, they fit a new floor to accommodate the iX5’s two cylindrical carbon fiber hydrogen tanks located in its center tunnel and under the rear seat. Fuel capacity amounts to about 16 pounds of gaseous hydrogen pressurized to 10,150 psi, which is good for about 310 miles of estimated range according to Europe’s optimistic WTLP methodology (which equates to about 260 miles of range in the US, according to the EPA’s cycles). Unlike with a BEV, refilling the iX5 at one of the hydrogen stations around Antwerp only takes a few minutes and will be familiar to anyone who has ever pumped their own gas.
Underneath the iX5’s boot is a rear-drive axle and upstream synchronous motor from a BMW iX. On top of that sits a 400-volt lithium-ion battery with about 2.0 kWh of usable capacity, which acts as a power buffer for the fuel cell to help with acceleration and also to recover energy under braking. The fuel cell stack itself is under the iX5’s hood and contains core cell elements from BMW’s long-time FCV partner, Toyota. BMW developed the rest of the assembly, including the stack’s cooler and humidifier that optimize the system’s air quality, plus a powerful compressor to quickly push oxygen into the cells’ membranes, where the main chemical reaction takes place. According to BMW, these improvements result in quick response to throttle input and the fuel cell’s ability to continuously operate at maximum power. As with all FCVs, electricity and water vapor are the only byproducts, with total system output a respectable 395 horsepower.
You’ll be able to spot the iX5 by its very blue accents and the decals that run across its hood and along its flanks. From behind the wheel, the experience is completely uneventful, which is the point. This vehicle drives exactly as you would expect an electric X5 to—smooth, quiet, and refined. Its steering is pleasantly direct, and its air springs and adjustable dampers return nicely balanced body movements. Ride comfort on our sample car’s 20-inch run-flat winter tires was good, although the standard 22-inch Pirelli P Zeros are bound to break it down a bit. Various drive modes vary the iX5’s sportiness accordingly, while paddles on its steering wheel adjust the regenerative braking from a little to quite a lot. Hit the right pedal, and the Bimmer accelerates briskly with the low-end punch of a BEV, thanks in part to the fuel cells’ ability to simultaneously contribute energy to the traction motor and help maintain a high state of charge for the battery. Traffic jams during our drive gave us no opportunity for fun, but BMW’s claims of acceleration to 62 mph in about six seconds and a 115 mph top speed are entirely credible.
Along with being easier to refuel, the iX5 highlights additional advantages of FCVs over comparable BEVs. For one, fuel cell vehicles tend to be lighter, mostly because they require only a modestly sized battery; BMW says the iX5’s curb weight is similar to that of the X5 plug-in hybrid, the latter of which weighed 5627 pounds. Of course, the similarly sized electric iX, with its huge 105.2 kWh pack, is barely heavier, but its structure uses more lightweight materials than the X5’s worth of several hundred pounds of weight reduction. Another advantage for FCVs is that their smaller battery means they require significantly fewer elements that are now in high demand to produce, such as lithium, cobalt and nickel, although small amounts of platinum are required for the fuel cell itself. The performance of fuel cells is also more stable in extreme temperatures, especially in the cold. While freezing water releases inside a fuel cell can indeed be a problem, BMW says the iX5 overcomes this by using compressed air to blow residual water out of its cells and into drainage circuits. As for those wondering what happened to BMW’s previous work on hydrogen internal combustion engines, technical issues and the inherent similarities between FCVs and BEVs killed that business case.
Proponents of FCVs argue that because of their strengths, particularly their reduced mass and reduced need for exotic materials, fuel cells scale well in larger applications, such as heavy trucks and ships with enough space to house substantial storage tanks. Major industries such as steel processing are also starting to use hydrogen, and BMW is betting that such applications will be key to the future development of FCVs. Indeed, the company’s strategy relies on hydrogen becoming more practical (and affordable) for transportation use as its popularity increases in other sectors. “It’s all about timing,” said Oliver Zipse, chairman of BMW’s management board, comparing an upcoming trigger point of hydrogen’s expected wider adoption to what lithium-ion batteries have done for BEVs.
But don’t expect to see an iX5 in your driveway anytime soon. BMW views this FCV pilot program as similar to its initial limited deployment of BEVs, which included the first Mini E in 2009 and the BMW ActiveE in 2012. But even as the company develops versatile vehicle architectures to support fuel cell propulsion systems, FCVs will primarily be a complementary — and likely subsidized — technology in markets willing to tackle the complicated economics of getting hydrogen to consumers. Persistent supply disruptions in Europe, for example, have raised the cost of hydrogen significantly above that of gasoline and diesel on a per-mile basis. Of course, none of this helps with long-term sustainability unless hydrogen is produced using clean energy sources such as wind, solar and nuclear, among others. In short, as compelling as BMW’s hydrogen technology may be, it is only a small piece in the future energy puzzle.
Technical editor
Mike Sutton is an editor, writer, test driver and general car geek who has contributed to Car and Driver‘s reverent and irreverent passion for the car since 2008. A native Michigander from suburban Detroit, enjoys the outdoors and complains about the weather, has a love of off-road vehicles, and believes in federal protection for naturally aspirated engines.
