Membranes and Materials for Energy Efficiency – Metal Hydride Materials for Compression Metal hydride material development for high efficiency and low cost hydrogen compressors

To make the hydrogen economy realistic at a large scale, one of main technical issues to be overcome is relative to the high pressure hydrogen delivery. Traditional hydrogen compressors suffer from high operating and maintenance costs and high capital investment. Metal hydride based compressors represent a realistic alternative that can potentially overcome all of the technical hurdles of the traditional mechanical systems. However, to date, the metal hydrides, available for this type of application (e.g. rare earth based materials), are generally based on expensive compounds and elements. This proposed project aims to establish a materials-genome based high throughput technique to define and develop a new class of materials for hydrogen compression. Specific material properties, required to meet the techno-economic targets for hydrogen compression systems, will be identified. After validation of the high throughput methodology by comparing the results with the available material data, the technique will be applied to identify new material formulations that meet the targets. The new material will be fully characterized in terms of thermodynamic, physical, kinetics properties and cycling performance. A new compression system will also be designed based on the new material, coupled with an effective heat transfer system. The compressor will be built at a laboratory scale, scaled up and commercialized during the further phases of the project. During Phase 1, the project will focus on the development and validation of the high throughput technique to define the new material formulation. The first step of the project will focus on identifying the material properties required to meet the techno-economic targets of hydrogen compression systems. This will guide the material development, through the high throughput analysis. The methodology, developed during Phase 1, defines the techniques for material hydrogenation, material characterization (in terms of thermodynamic and kinetics properties) and post cycling material evaluation. In addition, during Phase 1 of the project a new class of materials, having the potential to meet the targets, will be preliminarily identified, using computational thermodynamic programs. The new compression system will be instrumental in the development of a hydrogen economy on a large scale. The introduction of a metal hydride based compression system will eliminate the need for electric power to compress hydrogen, requiring only low temperature heat. This results in reduction of the system operating costs as well as in the possibility of coupling the system with many plants and facilities, reusing their waste heat and water. Moreover, the maintenance efforts required for this type of system, which has no moving parts, are considerably lower than those required for traditional mechanical compressor. The system will be introduced first in small scale industrial environments (e.g. to deliver high pressure hydrogen for forklifts), with subsequent penetration in medium to large scale applications (e.g. to reuse wasting heat available from agricultural facilities or, directly, from hydrogen production and chemical plants).