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Due to its high hydrogen storage capacity (up to 16% by weight for the release of 2.5 molar equivalents of hydrogen gas) and its stability under typical ambient conditions, ammonia borane (AB) is a promising material for chemical hydrogen storage for fuel cell applications in transportation sector. Several systems models for chemical hydride materials such as solid AB, solvated AB and alane were developed and evaluated at Pacific Northwest National Laboratory (PNNL) to determine an optimal configuration that would meet the 2010 and future DOE targets for hydrogen storage. This paper presents an overview of those systems models and discusses the simulation results for various transient drive cycle scenarios.

Portable life support systems must be capable of performing thermal management in a wide variety of environments. A microchannel-based LiBr-H2O absorption cooler may make radiator cooling more attractive than water sublimation in high temperature environments by increasing the temperature and in turn reducing the required surface area of the radiator. This study showed that such a heat pump can lift the radiator temperature from 15°C to 60°C with a coefficient of performance of 0.65 and reduce the radiator area by up to 60%. Proof-of-concept testing using microchannel technology has been demonstrated. This technology should enable the LiBr-H2O absorption cooler by reducing its overall mass and improving heat and mass transfer rates in the absorber.