In the race to bring hydrogen-fueled cars to market, virtually every manufacturer has settled on the compressed gaseous form with one notable exception. BMW has been the lone holdout for the use of liquid hydrogen. BMW's rationale is that liquid hydrogen is more dense than hydrogen gas, even when compressed to 10,000psi. Unfortunately getting hydrogen into liquid form, requires chilling it down to -282.57C -252.87C. Keeping it at that temperature requires a lot of insulation and hence a very bulky storage tank. Nonetheless, insulation is not perfect and the liquid hydrogen still warms up over time and boils. The vapor hydrogen then has to be vented to atmosphere. A BMW Hydrogen 7 left sitting for a week will end up with an empty hydrogen tank.
BMW has been working with a consortium of 34 automakers, aerospace, fuel companies, and universities for the past four and a half years to develop a new storage system for liquid hydrogen. The current cylindrical steel tanks are both heavy and challenging to package in a car and end up absorbing most of the trunk space. BMW's research and development arm Forschung und Technik, along with the consortium, has developed a new composite modular design that can be formed into different shapes allowing greater packaging flexibility. The new tank is claimed to be one third of the weight of the current tank design. It's not known if the new tank does anything to address the issue of fluid boiling. BMW will display the new tank at the StorHy conference in Poissy, France this week.
[Source: BMW]
| Munich. BMW Group Forschung und Technik, the company's research and technology arm, has been working with other car manufacturers to achieve an important step forward in hydrogen storage. Teaming up with partners, including some from the European aerospace industry, the engineers have developed a novel type of tank made of composite material for storing liquid hydrogen.
Thanks to its innovative concept, the weight of the entire tank system can be reduced to a third compared with conventional cylindrical steel tanks. Its adaptable form lends it a high degree of flexibility, allowing for significant energy savings. The subsidiary systems, moreover, are integrated inside the tank's casing, which means the tank takes up less room in the car and maintenance is also made much easier. The inner tank is designed on a modular basis, simplifying the production process in comparison with existing hydrogen tanks. Prof. Dr.-Ing. Raymond Freymann, Director of BMW Group Forschung und Technik: “The demonstration model of the new free-form tank being presented marks an important step forward into the hydrogen future. Filled with ten kilograms of hydrogen, it could allow a range well in excess of 500 kilometres in a future vehicle.” BMW Group Forschung und Technik is presenting the prototype of this innovative liquid hydrogen storage tank at the final event of the “StorHy” EU project in Poissy near Paris on 3 and 4 June 2008. In the past four and a half years BMW Group Forschung und Technik, along with 34 partners from the European aerospace industry, the automotive and supply industry, and leading universities and research institutes, has been investigating ways of advancing current hydrogen storage technologies (high-pressure, liquid and solid storage). The cost of the project was 18.7 million euros, with EU funding to the sum of 10.7 million euros. BMW Forschung und Technik GmbH is a 100% subsidiary of BMW AG and has been responsible for research within the BMW Group since 2003. Its subject areas cover VehicleTechnology, CleanEnergy (hydrogen technology), EfficientDynamics (intelligent energy management/alternative drive systems), ConnectedDrive (driver assistance/active safety) and ITDrive (IT and communications technology). Its legal independence as a limited company guarantees creative freedom and maximum flexibility. Global access to new trends and technologies is ensured by an internationally established network with branches in the USA (Palo Alto, CA and Clemson, SC), Japan (Tokyo) as well as liaison offices in France with Eurécom (Sophia Antipolis) and in Germany (Saarbrücken) with the German Research Centre for Artificial Intelligence (DFKI GmbH). The StorHy consortium: |
https://www.autoblog.com/2008/06/02/bmw-develops-lighter-smaller-liquid-hydrogen-tank/
2008-06-02T17:22:00+00:00