Low-pressure Hydrogen Storage Research Articles

Sorption properties of nanostructured ball-milled porous silicon for solid-state hydrogen storage up to 80 bar

Solid-state storage is a feasible solution to store hydrogen compared to commercially available techniques. The disadvantage of using metal and complex hydrides for storage is the elevated temperature operation (>400 °C) and slow reaction kinetics. Porous materials like carbon nanostructures, metal-organic frameworks, zeolites, and porous polymers possess high surface energy and hydrogen affinity. However, cryogenic temperature operation and low storage at ambient conditions are major limitations for practical storage applications. Modifying the material morphology and storage parameters to enhance hydrogen storage is under intense investigation. This study focuses on nanostructuring porous silicon (PS), evaluating its structural characteristics, and investigating its ability to store hydrogen at up to 80 bar. The challenges of large particle size and low-pressure hydrogen storage in the novel porous material is addressed with possible mechanisms. The discussion explored the potential of utilizing interconnected pores via nanoscale engineering and increased charging pressure to optimize hydrogen exposure. Nanostructuring the hand-grinded porous Si (HGPS) reduces crystallite size, boosts surface energy and enhances thermodynamics. At 80 bar and 120 °C, the ball-milled PS (BMPS) exhibits a hydrogen storage capacity of 10.7 wt%. The isosteric heat of adsorption is utilized to optimize storage conditions to achieve useable capacity. The hydrogen adsorption pressure is optimized between 40 and 60 bar, where the storage capacity ranges from 2 wt% and 6 wt% (meeting the hydrogen storage target set by the US Department of Energy). X-ray Photoelectron Spectroscopy investigates surface states and bonding involving silicon hydrides. The effect of nanostructuring on decomposition energy is observed by differential scanning calorimetry. The decreased crystallite size, examined through X-ray diffraction and Raman spectroscopy, exposes nanopores accessible to hydrogen. The accessibility enhances storage capacity in free and surface-affixed states, rendering BMPS for reversible storage applications. The lower temperature requirement for hydrogen adsorption and release from storage material aligns with Sustainable Development Goal 7 (SDG 7) on affordable and clean energy.

Study on the Combination of Low-Pressure Hydrogen Cylinder and Non-sintered Ceramic Wall to Solve Water Permeability

Global green energy development by many technological breakthroughs, so that the new composite materials modified and designed, so that new energy has a new look, this study to improve people’s high-pressure hydrogen storage of hydrogen energy technology hazards and hidden worries, so design and improve the local low-pressure hydrogen storage combined with secondary building wall design, and sustainable environmental thinking, The use of waste ceramic reuse technology, combined with low-pressure hydrogen bottle design to form a new composite material structure, and the best parameters to solve waterproof non-sintered ceramic clad metal material research, and OM, salt spray, perspective X-RAY observation with metal now ceramic anti-corrosion permeability, the future use of geotechnical engineering, building diversification. More so that hydrogen in non-high pressure, more in people’s life circle and local hydrogen storage and PC use. Thank partially support by the MOST 108-2221-E-343-001.

Assessing the operation and different refuelling cost scenarios of a fuel cell electric bicycle under low-pressure hydrogen storage

The transition to low- or zero-emission vehicles in the transportation sector is a challenging task toward meeting the greenhouse gas emission targets set by the majority of countries. One way of achieving this goal is to utilise hydrogen gas via fuel cell electric vehicles. This paper investigates the operation, driving range and refuelling process of a fuel cell electric bicycle. The methodology applied includes an estimation of the bike's range under different routes and riders, the riders' opinions and a financial evaluation of the hydrogen fuel cost compared to other urban vehicle alternatives. The results showed a minimum median range-to-energy consumption ratio of 20.5 km/kWh, while the maximum hydrogen cost was found to reach 0.025 €/km when refuelling the hydrogen bicycle in an autonomous hydrogen station. The outcome of this study indicates that the introduction of light-duty hydrogen vehicles in urban transportation may adequately meet the average daily driving distance of city residents.

High capacity, low pressure hydrogen storage based on magnesium hydride and thermochemical heat storage: Experimental proof of concept

With hydrogen becoming more and more important as energy carrier, there is a need for high capacity storage technologies preferably operating at low pressures. Chemical storage in metal hydrides is promising for that purpose, but they require thermal management for hydrogen release and storage, respectively. To overcome this challenge, it is beneficial to store the heat needed for hydrogen release during hydrogen storage in the storage system keeping the additional effort to provide that heat low. In this work, the experimental proof of concept of an adiabatic storage reactor is presented. Magnesium hydride and magnesium hydroxide have been used for hydrogen storage and thermochemical heat storage, respectively. A prototype reactor has been developed and experimentally investigated. It was found that the operating temperature of the materials can be adjusted with the gas pressure in a way to establish a temperature gradient from the MgH2 to the Mg(OH)2 and vice versa. Hydrogen storage and release is enhanced by the thermochemical heating/cooling. A pressure of 9 bar is sufficient to store hydrogen with a capacity of 20.8 gH2 L-1 based on the two materials only, without the steel vessel or insulation. In the heat storage compartment, 300 °C have been reached at 9.75 bar during heat release which is high enough to drive the MgH2 dehydrogenation.

Beyond Idealized Models of Nanoscale Metal Hydrides for Hydrogen Storage

Metal hydrides are attractive for compact, low-pressure hydrogen storage, yet a foundational understanding of factors governing their thermodynamics and kinetics is still lacking. Predictive modeli...

Silica rich MIL-101(Cr) for enhanced hydrogen uptake

Hybrid composite of MIL-101 with silica rich rice husk ash (RHA) was fabricated to explore such materials for improved low pressure hydrogen storage applications, compared to the well explored carbon based composites of MIL-101. RHA–MIL-101 was prepared by in situ incorporation of RHA in MIL-101 during the synthesis, under hydrothermal conditions. The incorporation of RHA in MIL-101 was confirmed by P-XRD, FTIR, TGA, SEM, EDS, and N2 adsorption and desorption isotherms studies. The as-synthesized RHA–MIL-101 composite displayed enhanced BET surface area (8.6% compared to bare MIL-101), whereas AC–MIL-101 showed an enhancement of 12.7% in BET surface area compared to bare MIL-101. Hydrogen uptake properties of these materials were evaluated at 77 K and 1 bar. Despite that RHA–MIL-101 exhibited lower surface area as compared to AC–MIL-101, the hydrogen uptake capacities of RHA–MIL-101 reached an enhanced value of 1.54 wt%, which is obviously higher than the bare MIL-101 (1.40 wt%) and AC–MIL-101 (1.48 wt%) by 9.1% and 5.7%, respectively, as well as comparable to most of the reported carbon incorporated MOFs. It has been observed that improved hydrogen uptake properties was due to the bifunctional properties of the synthesized RHA–MIL-101, abundance of silanol bonds of RHA (which shows high affinity towards H2 molecules), and tuned porous properties of RHA–MIL-101. Moreover, hydrogen adsorption isotherms data of these materials were best fitted with three parameter non-linear adsorption equilibrium isotherm equations.

Developing Hybrid–Power Fuel Cells with a Low–Pressure Hydrogen–Storage System used in an Electric Forklifts

Developing Hybrid–Power Fuel Cells with a Low–Pressure Hydrogen–Storage System used in an Electric Forklifts

Integration of low-pressure hydrogen storage cylinder and automatic controller for carbon deposit removal in car engine

This study has completed the preliminary test of the “automotive hydrogen gas release controller with low pressure hydrogen storage module” in the carbon removal of cars engine, this product has integrated (1) a low pressure hydrogen storage cylinder (metal hydride) and (2) a solenoid valve controller with flow meter. Under normal temperature and pressure settings, this system is able to transfer hydrogen gas to the vehicle's intake air system and mixing with the air, entering the engine chamber. The solenoid valve controller and flow meter can control the optimized hydrogen gas output flow rate, activating the carbon deposit removal. The results of this study show that in the example for a 1,600 cc vehicle, 1690 USD may be saved for gasoline in a year with reducing 164.8 ton of CO2 emission (The enhancing of fuel utilization 11.6%). For a 2,000 cc vehicle, 3070 USD may be saved for gasoline in a year with reducing 291 ton of CO2 emission (The enhancing of fuel utilization 20.6%). A set of low pressure hydrogen storage system has been developed in this research, it is safe and convenient for consumers, the Solenoid Valve Controller and Flow meter allows for optimized use of hydrogen gas, reducing the waste of excess hydrogen gas.

Fuel Cell Hybrid Electric Scooter

In this article, the structure and control of a fuel cell hybrid electric scooter for mass production are presented. The development of a zero-emission scooter can improve air quality and protect the environment, especially in Asia and Europe, where more than 25 million scooters are produced annually. The generic advantages of low-pressure hydrogen storage of the fuel-cell-powered scooter are explained, and the control strategies of the hybrid scooter are presented. Additionally, experimental verifications and discussions are presented based on a prototype system controller.

Renewable and hydrogen energy integrated house

The residential sector accounts for about a third of the total world energy consumption. Energy efficiency, Renewable Energy Sources and Hydrogen can play an important role in reducing the consumptions and the emissions and improving the energy security if integrated (Efficiency, Res, Hydrogen) systems are developed and experimented. The paper analyzes a real residential 100 square meters house, where energy efficiency measures and RES technologies have been applied, sizing a hydrogen system (electrolyzer, metal hydrides and fuel cell) for power backup, taking into consideration its dynamic behavior, experimentally determined. The technologies used are already available in the market and, except hydrogen technologies, sufficiently mature. Through energy efficiency technologies (insulation, absorbers, etc), the maximum electrical and thermal power needed decreases from 4.4 kW e to 1.7 kW e (annual consumption from 5000 kWh to 1200 kWh) and from 5.2 kW t to 1.6 kW t (annual consumption from 14,600 kWh to 4500 kWh) respectively. With these reduced values it has been possible to supply the consumptions entirely by small photovoltaic and solar thermal plants (less than 10 m 2 each). The hydrogen backup even if remains the most expensive (versus traditional batteries and gasoline generator), satisfying all the electric needs for one day, increases the security and allows net metering. Moreover the low-pressure hydrogen storage system through metal hydrides guarantees system safety too. Finally the system modularity can also satisfy higher energy production.

Design of Power System Control in Hybrid Electric Vehicle

This paper proposes a design of power system control in the hybrid electric vehicle. It adopts the isolated DC/DC power converter as the front-end fuel cell and Lithium-ion battery to supply constant voltage. By micro-controller to detect the hybrid power output, and the low-pressure hydrogen storage temperature, and the adjustment of the power output ratio to provide the energy for loading balance. The results can obtain the overall performance of electric vehicle. It is important to avoid the excessive usage of hydrogen fuel which causes the phenomenon of storage tank freezing and fuel cell or Lithium-ion batteries abnormal situation. Display the working data of hybrid power system can achieve the capability of instant surveillance. For the loading under consideration, the fuel cell and Lithium-ion battery can supply stable voltage output. Copyright Form of EVS25.

A Technological Solution for an Everywhere Energy Supply With Sun, Hydrogen, and Fuel Cells

The hydrogen economy is still at the beginning, but society, innovation, and the market push inexorably toward hydrogen, inspiring the idea to build an energy-integrated system that can satisfy, in an independent way, the energy needs of small-sized consumers. The technologies used for the system design are already available in the market and, at least for the standard solutions, sufficiently mature. The innovation consists of an integration, optimization, and industrialization of this modular system, which is an electric zero-emissions generator, giving 3.5kWp as an output power. This is the only system able to produce its own fuel, guaranteeing renewable and clean energy, available where and when you want. This system is constituted by a polymer membrane electrolyzer, a metal hydrides tank (which absorbs and desorbs hydrogen), and a polymer fuel cell (PEM). The system modularity can also satisfy higher energy requirements, and the low-pressure hydrogen storage system through metal hydrides guarantees the system safety.

Enhancing low pressure hydrogen storage in sodium alanates

We investigated the dehydrogenation of NaAlH4 and the reversible low-pressure rehydrogenation from NaH to Na3AlH6. Highly purified NaAlH4 requires relatively high temperatures to decompose to NaH and long durations to rehydride to the Na3AlH6 phase in hydrogen gas. However, any degradation of the purity of this material, whether through ball milling with diamond powder or ball milling with diamond plus Al powders, mixing the purified material with Pt powder, or doping with a Ti organometallic compound, lowers the decomposition temperature and facilitates rehydriding the product NaH+Al to Na3AlH6. Diamond ball milling of NaAlH4 seems to be the best of these procedures; it substantially decreases the decomposition temperatures, with significant dehydrogenation starting at 180°C rather than 250°C for the purified material, and with formation of NaH substantially complete at 235°C rather than 290°C. Rather surprisingly, it also facilitates rehydrogenation from NaH+Al to Na3AlH6. Similarly, NaAlH4 doped with Ti according to the recipe of Bogdanović lowers the decomposition temperatures and improves the hydrogenation kinetics for the low pressure transition from NaH+Al to Na3AlH6. Pressure–composition isotherms show that the rehydrogenation of the resulting NaH+Al decomposition phases into the Na3AlH6 intermediate phase at pressures below 3.6 MPa is similar for the diamond ball milled and Ti-doped material. Diamond ball milling NaAlH4 with excess Al did not improve the rehydrogenation kinetics.