Sigma-Aldrich and Ilika Technologies collaborate to scale-up and commercialize boron hydride hydrogen-storage materials
Aldrich Materials Science, a strategic technology initiative of Sigma-Aldrich Corporation, has signed an agreement to collaborate on the scale-up and commercialization of next-generation boron hydride hydrogen-storage materials with Ilika plc, an advanced cleantech materials discovery company.
To be economically viable, the target weight percentage of hydrogen stored in such a material has been set at 6% by the US Department of Energy. Current commercially available hydride materials can achieve up to 2.3 weight% of hydrogen; the hydride materials being verified and scaled-up by Aldrich Materials Science can potentially store up to 10 weight% of hydrogen, reversibly, the company says.
The main criteria for hydrogen storage for transport purposes, as outlined by the US Freedom Car Initiative, are to supply enough hydrogen to enable a driving range of approximately 500 km (311 miles); to charge and recharge at near room temperature; and to provide hydrogen at rates fast enough for vehicular operation—from cars to trains.
Current prototype applications use very high pressure compressed hydrogen or cryogenically cooled liquid hydrogen. These methods consume a significant percentage of the energy content in their compression and conversion and both raise safety concerns. Ilika’s storage solution is a solid metal hydride, which exists as a powder stored in a cylinder at moderate pressure and stable at room temperature. When warmed to moderate temperatures, hydrogen is released for use as fuel.
Boron-based hydrogen storage. Boron belongs to a class of elements that can bind significant amounts of hydrogen and release it under mild experimental conditions. Boron-based materials, specifically boron hydrides, can store up to 19% hydrogen by weight and release it at the temperatures ranging from 100 °C to 400 °C or upon chemical treatment. The most recent generation of boron hydrides evaluated as high-capacity hydrogen storage media are largely based on reversible magnesium and calcium borohydrides or lithium ammonia borane, notes Sigma-Aldrich.
Other materials of interest for hydrogen storage are ammonia borane, which releases ~ 13% of hydrogen in two steps at temperatures exceeding 100° C; and lithium and sodium borohydrides, which are capable of an irreversible hydrogen release in aqueous solutions in the presence of metal catalysts.