A Review of Heat Transfer Issues in Hydrogen Storage Technologies

Significant heat transfer issues associated with four alternative hydrogen storage methods are identified and discussed, with particular emphasis on technologies for vehicle applications. For compressed hydrogen storage, efficient heat transfer during compression and intercooling decreases compression work. In addition, enhanced heat transfer inside the tank during the fueling process can minimize additional compression work. For liquid hydrogen storage, improved thermal insulation of cryogenic tanks can significantly reduce energy loss caused by liquid boil-off. For storage systems using metal hydrides, enhanced heat transfer is essential because of the low effective thermal conductivity of particle beds. Enhanced heat transfer is also necessary to ensure that both hydriding and dehydriding processes achieve completion and to prevent hydride bed meltdown. For hydrogen storage in the form of chemical hydrides, innovative vehicle cooling design will be needed to enable their acceptance.

Download Full-text

On-Board and Off-Board Technologies for Hydrogen Storage

Hydrogen Fuel Cell Technology for Stationary Applications - Advances in Computer and Electrical Engineering ◽

10.4018/978-1-7998-4945-2.ch006 ◽

2021 ◽

pp. 139-165

Author(s):

Madhavi Konni ◽

Saratchandra Babu Mukkamala ◽

Manoj Kumar Karnena

Keyword(s):

Hydrogen Storage ◽

Alternative Fuels ◽

Hybrid Methods ◽

Renewable Energy Resources ◽

Promising Alternative ◽

Physical Methods ◽

Significant Challenge ◽

Storage Methods ◽

Storage Technologies ◽

Physical And Chemical

Future energy systems will be determined by the increasing relevance of renewable energy resources due to global warming, energy crisis, and pollution. Hydrogen is considered one of the promising alternative fuels to replace oil, but its storage remains a significant challenge. The main hydrogen storage technologies can be broadly classified as physical, chemical, and hybrid methods. The physical methods rely on compression and liquefaction of hydrogen, and currently, compressed hydrogen storage is the most mature technology that is commercially available. The chemical methods utilize materials to store hydrogen, and hydrogen can be extracted by on-board regenerable or off-board regenerable chemical reactions depending on the type of material. Hybrid methods take advantage of both physical and chemical storage methods. The most prominent hybrid method is the cryo-adsorption hydrogen storage which utilizes physisorption-based porous materials. The chapter describes these technologies and discusses alternative/novel hydrogen storage material technologies.

Download Full-text

Computational Study of Hydrogen Storage Performance in Metal Hydride Reactors

ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 1 ◽

10.1115/esda2010-24059 ◽

2010 ◽

Author(s):

Chih-Ang Chung ◽

Ci-Siang Lin ◽

Ci-Jyun Ho

Keyword(s):

Heat Transfer ◽

Hydrogen Storage ◽

Gas Flow ◽

Computational Study ◽

Metal Hydrides ◽

Reaction Rates ◽

High Energy ◽

Hydrogen Gas ◽

High Energy Density ◽

Equilibrium Pressure

Hydrogen as the most abundant element on Earth is viewed to be a promising energy carrier. For transmission, hydrogen stored as metal hydrides is a potent candidate for its advantages in safe and reliability and being able to offer high energy density compared to the conventional ways such as high pressure gas and liquefaction. Metal hydriding is basically an exothermic process. The heat released will cause an increase in temperature and raise the absorption equilibrium pressure as high as that of the supplied hydrogen gas, which may in turn stop the hydriding process. On the other hand, metal dehydriding is an endothermic process. A temperature decrease can retard desorption and even bring down the dissociation equilibrium pressure as low as the back pressure to stop dehydriding. Therefore, reducing thermal resistance of the storage vessels and enhancing heat transfer of the storage system have become a critical issue for the success of hydrogen storage using metal hydrides. This work models the metal hydriding/dehydriding process in order to assess the vessel design on heat transfer enhancement to improve the performance of hydrogen storage with metal hydrides. First of all, the thermal-fluid behavior of hydrogen storage was modeled including gas flow and energy equations. The vessel is considered to be equipped with an air pipe at the centre line with internal fins. Detailed theoretical models that describe force convection of the heat exchange pipe and natural convection at the lateral wall are constructed. Results from the simulation show that the addition of a concentric heat exchanger pipe with fins can enhance the reaction rates. The work demonstrates how computer aided engineering can be applied to evaluate the performance of hydrogen storage designs, and help reduce experimental efforts in developing the hydrogen storage systems.

Download Full-text