Systems Modeling of Chemical Hydride Hydrogen Storage Materials for Fuel Cell Applications

2011 ◽  
Vol 8 (6) ◽  
Author(s):  
Kriston Brooks ◽  
Maruthi Devarakonda ◽  
Scot Rassat ◽  
Jamie Holladay
Keyword(s):  
Fuel Cell ◽  
Hydrogen Storage ◽  
Storage System ◽  
Fixed Bed ◽  
Hydrogen Gas ◽  
Fixed Bed Reactor ◽  
Ambient Conditions ◽  
High Hydrogen ◽  
Pressure Drops ◽  
Reactor Models

A fixed bed reactor was designed, modeled and simulated for hydrogen storage on-board the vehicle for PEM fuel cell applications. Ammonia borane was selected by DOE’s Hydrogen Storage Engineering Center of Excellence as the initial chemical hydride of study because of 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. The design evaluated consisted of a tank with eight thermally isolated sections in which H2 flows freely between sections to provide ballast. Heating elements are used to initiate reactions in each section when pressure drops below a specified level in the tank. Reactor models in Excel and COMSOL were developed to demonstrate the proof-of-concept, which was then used to develop systems models in Matlab/Simulink. Experiments and drive cycle simulations showed that the storage system meets thirteen 2010 DOE targets in entirety and the remaining four at greater than 60% of the target.

Systems Modeling of Ammonia Borane Bead Reactor for Off-Board Regenerable Hydrogen Storage in PEM Fuel Cell Applications

2010 ◽  
Author(s):  
Kriston Brooks ◽  
Maruthi Devarakonda ◽  
Scot Rassat ◽  
Dale King ◽  
Darrell Herling
Keyword(s):  
Fuel Cell ◽  
Hydrogen Storage ◽  
Pem Fuel Cell ◽  
Ammonia Borane ◽  
Hydrogen Gas ◽  
Reactor System ◽  
Automotive Application ◽  
State Variables ◽  
High Hydrogen ◽  
System Pressure

Research on ammonia borane (AB, NH3BH3) has shown it to be a promising material for chemical hydrogen storage in PEM fuel cell applications. AB was selected by DOE’s Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to 19.6% by weight for the release of three molar equivalents of hydrogen gas) and its stability under typical ambient conditions. A model of a bead reactor system was developed to study AB system performance in an automotive application and estimate the energy, mass, and volume requirements for this off-board regenerable hydrogen storage material. The system includes feed and product tanks, hot and cold augers, a ballast tank/reactor, a H2 burner and a radiator. One-dimensional models based on conservation of species and energy were used to predict important state variables such as reactant and product concentrations, temperatures of various components, flow rates, and pressure in the reactor system. The flow rate of AB into the process and the system pressure were governed by a control system which is modeled as an independent subsystem. Each subsystem in the model was coded as a C language S-function and implemented in the Matlab/Simulink environment. Preliminary system simulation results for a start-up case and for a transient drive cycle indicate appropriate trends in the reactor system dynamics.

The PEM Fuel Cell System for Autonomous Underwater Vehicles

2005 ◽  
Vol 39 (3) ◽  
pp. 56-64 ◽  
Author(s):  
Satoshi Tsukioka ◽  
Taro Aoki ◽  
Ikuo Yamamoto ◽  
Hiroshi Yoshida ◽  
Tadahiro Hyakudome ◽  
...  
Keyword(s):  
Fuel Cell ◽  
Metal Hydride ◽  
Autonomous Underwater Vehicle ◽  
Earth Science ◽  
Autonomous Underwater Vehicles ◽  
Storage System ◽  
Cell System ◽  
Hydrogen Gas ◽  
Fuel Cell System ◽  
Control Electronics

An ocean-going autonomous underwater vehicle powered by a polymer electrode membrane fuel cell system was completed by The Japan Agency for Marine-Earth Science and Technology. The fuel cell system generates 4kW of electric power for the control electronics and propulsion system. Hydrogen gas is stored under low pressure in the metal hydride. Heat generated by the fuel cell is used to discharge hydrogen gas into the metal hydride. This paper presents the test results of the fuel cell, storage system and the 317km sea test.

scholarly journals Hydrogen Storage in Propane-Hydrate: Theoretical and Experimental Study

2020 ◽  
Vol 10 (24) ◽  
pp. 8962
Author(s):  
Mohammad Reza Ghaani ◽  
Satoshi Takeya ◽  
Niall J. English
Keyword(s):  
Hydrogen Storage ◽  
Storage Capacity ◽  
Fixed Bed ◽  
Hydrogen Uptake ◽  
Hydrogen Release ◽  
Fixed Bed Reactor ◽  
Gas Dispersion ◽  
Fixed Bed Reactors ◽  
Non Equilibrium Molecular Dynamics ◽  
Kinetics Of

There have been studies on gas-phase promoter facilitation of H2-containing clathrates. In the present study, non-equilibrium molecular dynamics (NEMD) simulations were conducted to analyse hydrogen release and uptake from/into propane planar clathrate surfaces at 180–273 K. The kinetics of the formation of propane hydrate as the host for hydrogen as well as hydrogen uptake into this framework was investigated experimentally using a fixed-bed reactor. The experimental hydrogen storage capacity propane hydrate was found to be around 1.04 wt% in compare with the theoretical expected 1.13 wt% storage capacity of propane hydrate. As a result, we advocate some limitation of gas-dispersion (fixed-bed) reactors such as the possibility of having un-reacted water as well as limited diffusion of hydrogen in the bulk hydrate.

scholarly journals Metastable Metal Hydrides for Hydrogen Storage

2012 ◽  
Vol 2012 ◽  
pp. 1-18 ◽  
Author(s):  
Jason Graetz
Keyword(s):  
New Media ◽  
Hydrogen Storage ◽  
High Capacity ◽  
Metal Hydrides ◽  
Decomposition Reaction ◽  
Hydrogen Gas ◽  
Production Costs ◽  
Ambient Conditions ◽  
New Methods ◽  
Decomposition Enthalpy

The possibility of using hydrogen as a reliable energy carrier for both stationary and mobile applications has gained renewed interest in recent years due to improvements in high temperature fuel cells and a reduction in hydrogen production costs. However, a number of challenges remain and new media are needed that are capable of safely storing hydrogen with high gravimetric and volumetric densities. Metal hydrides and complex metal hydrides offer some hope of overcoming these challenges; however, many of the high capacity “reversible” hydrides exhibit a large endothermic decomposition enthalpy making it difficult to release the hydrogen at low temperatures. On the other hand, the metastable hydrides are characterized by a low reaction enthalpy and a decomposition reaction that is thermodynamically favorable under ambient conditions. The rapid, low temperature hydrogen evolution rates that can be achieved with these materials offer much promise for mobile PEM fuel cell applications. However, a critical challenge exists to develop new methods to regenerate these hydrides directly from the reactants and hydrogen gas. This spotlight paper presents an overview of some of the metastable metal hydrides for hydrogen storage and a few new approaches being investigated to address the key challenges associated with these materials.

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