BMW’s patented flat storage system uses CFRP tanks for iX5 hydrogen

Source | BMW Group

The iX5 Hydrogen is part of the BMW Group’s (Munich, Germany) next-generation X5 lineup, featuring a highly flexible architecture available with five different powertrain options including gasoline, diesel, plug-in hybrid and battery-electric in addition to hydrogen (H2) fuel cell.

The BMW Hydrogen Flat Storage system enables fitting roughly ≈7 kilograms of H2 in the same available installation space while being fully compatible with the Gen6 high-voltage battery without compromising interior space. The system comprises seven 700-bar Type 4 pressure vessels made using a plastic liner overwrapped with carbon fiber-reinforced epoxy composite.

Instead of individual pressure vessels, they are connected in parallel to form an enclosed unit controlled by a central main valve and integrated into a robust metal frame. This optimized storage concept increases the range of the BMW iX5 Hydrogen — up to 750 kilometers while maintaining refueling in less than 5 minutes — and has resulted in several patent applications being filed by the BMW Group.

The new flat tank arrangement means fuel cell models can be built on the same production line as other models while the H2 tanks additionally benefit from the mechanical protection provided by the vehicle structure, increasing already proven safety even further. These models are equipped with latest Gen3 fuel cell technology, reportedly co-developed with Toyota, resulting in a system 25% more compact, as well as more powerful and efficient.

The iX5 Hydrogen will be rolled out across the BMW Group’s production network in 2028, starting with production of the fuel cell at BMW Group Plant Steyr, which draws on decades of development and production expertise covering all drive system types.

The BMW Group notes that a technology-open approach and diverse product portfolio remain key success factors. By integrating fuel cell technology into the new BMW X5, the company is strategically expanding its production lineup and making the benefits of H2 mobility available to customers. H2 offers electric driving with a long range and fast refueling, while diversifying energy sources and reducing dependence on a single infrastructure or raw material supply chain.