Metal Hydride Hydrogen Research Articles

Proton Exchange Membrane Fuel Cell Flow Field Configuration: Modelling and Experimental Verification

With climate change crisis the research community is forced to consider other alternatives for energy production. Therefore, renewable energy sources are today considered as the main replacement for fossil fuels in the future. Proton exchange membrane (PEM) fuel cells are gaining more attention as main power sources for powering various vehicles, such as cars, forklifts, golfcarts etc. [1, 2]. European Commission (EC) recognized the importance of the fuel cell and hydrogen technology and their inevitable role in reducing greenhouse gas emission by further encouraging hydrogen fuel cell integration in various vehicles in their hydrogen strategy for a climate-neutral Europe [3]. Beside water and heat management, one of the key elements of the PEM fuel cells are reactants flow field channels. Influence of flow direction, channel length and number of channels, cross-section shape, channel depth, channel to rib width ratio etc., on PEM fuel cell performances has been analysed in the literature. Improper design of flow field channels may lead to water stagnation and flooding and as a result poor fuel cell performance (polarization curve).The objective of this work is to find optimal flow field configuration – number of channels, channel width to rib ration and channel depth. To achieve this objective numerical modelling of PEMFC was done using Ansys 17.0, in which 3D geometry (via DesignModeler) was modelled and finite volumes mesh was generated. Developed model was simulated in Fluent, using computational fluid dynamic (CFD). Based on the simulation results, graphite bipolar plate with optimal channel design was machined, integrated into single PEM fuel cell unit with commercial MEA’s and tested. With the application of different geometrical parameters like the number of channels, channel width to rib ratio, channel depth, mass fraction of oxygen and heat transfer in the fuel cell can be optimized. Numerical modelling of PEMFC was done using Ansys 17.0, in which 3D geometry (via DesignModeler) was modelled and finite volumes mesh was generated. At last, PEMFC was simulated in Fluent, using computational fluid dynamic (CFD). After calibration of the based numerical model, simulations with improved flow field designs were created and compared to the based model. Flow field design which was configurated as 4 serpentines (counterflow mode) channels with the depth of 0.45 mm, resulted in the best improvement of performance comparing to the basic model. Obtained results were confirmed experimentally.References Tolj, I.; Lototskyy, M.V.; Davids, M.W.; Pasupathi, S.; Swart, G.; Pollet B.G. Fuel cell-battery hybrid powered light electric vehicle (golf cart): Influence of fuel cell on the driving performance. J. Hydrogen Energy 2013, 38, 10630-10639.Lototskyy, M.V.; Tolj, I. et al. Performance of electric forklift with low-temperature polymer exchange membrane fuel cell power module and metal hydride hydrogen storage extension tank. Power Sources 2016, 316, 239-250.Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions: A hydrogen strategy for a climate-neutral Europe, Brussels, 08.07.2020, https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52020DC0301&from=EN

Performance analysis of LaNi5 added with expanded natural graphite for hydrogen storage system

This paper presents a comparative study of two cases of metal hydride hydrogen storage units working on (i) LaNi5 (ii) Compacts of LaNi5 incorporated with expanded natural graphite (ENG). It has been observed from the previous studies that the hydriding/dehydriding reactions eventually causes large strain changes, due to which the hydride forming metal alloys disintegrate and form a powder bed. Such reactor beds usually have a low thermal conductivity which minimizes the heat transfer phenomenon occurring during the absorption of hydrogen gas. Therefore, there is a need to implement heat augmentation methods to significantly enhance the thermal conductivity. The objective of this research is to present a 2-D numerical model using Finite Volume Method (FVM) and estimate the hydrogen storage performance of a cylindrical metal hydride bed for both the cases, i.e. powdered metal hydride bed and ENG compacts-based reactor bed at different values of inlet pressure and heat transfer fluid temperature. In this study, a detailed investigation on the absorption process reveals that reactor beds with compacted disks of LaNi5 and ENG demonstrate an enhanced effective thermal conductivity and efficient mass transfer. The simulation results show that a remarkable improvement in the heat transfer and hydrogen storage capacity with reduced absorption time can be achieved by using LaNi5 and ENG compacts. It was observed that the average reactor bed temperature dropped from 345.13 K to 337.37 K when the ENG based compacted disks was introduced into the reactor bed. Moreover, for supply pressure of 24 bar and fluid temperature of 293 K, the time taken to absorb hydrogen into the rector to achieve stabilized hydrogen storage capacity was estimated to be 446s and 232 s for the case of metal hydride and ENG compacts-based bed, respectively.

A suitable design of metal hydride cartridge for a fuel cell assisted bicycle in consideration of heat transfer performance

Metal hydrides (MHs) can store hydrogen produced from biomass at low pressure and high volumetric energy density. However, the endothermic reaction that occurs during hydrogen discharge decreases the hydrogen flow rate, which prevents the generation of sufficient power for fuel cell (FC) devices. Because a previous study reported that the hydrogen capacity of MHs would drop by approximately 20% due to the hydrogen sulfide contained in hydrogen from biomass, the utilizable amount of hydrogen in MHs should be enhanced. In this study, MH utilization for an FC-assisted bicycle in consideration of waste heat recovery from MH to FC was investigated. The results show that the MH-based hydrogen storage system can weigh 8 kg or lower for the FC bicycle to travel twice the distance of a lithium-ion-battery-derived bicycle. Using the mathematical model of hydrogen discharge from the MH, the heat transfer of a small MH cartridge for the FC bicycle was investigated. The center of the cartridge cooled by approximately 20 K from the initial temperature, indicating the necessity of heat injection into the MH cartridge even if the initial and boundary temperatures were high. It was also concluded that 83% of the hydrogen charged in the MH could be utilized to maintain the hydrogen flow rate to run a 220 W FC.

Performance improvement of metal hydride hydrogen storage tanks by using phase change materials

In metal hydride based hydrogen storage tanks, heat transfer fluid (HTF) has been extensively used to continuously transfer the reaction heat for promoting the reaction via heat exchangers. In this study, the phase change material (PCM) is integrated with the tank to enhance heat transfer and recycle the reaction heat. A novel storage tank with a simple concentric straight-tube heat exchanger surrounded by PCM is put forward to improve the hydrogen storage performance. A numerical model is built to track the transfer and reaction process. By comparison, the new tank shows better heat transfer and storage performance, and the hydrogen absorption time is shortened by 60.2% than that of the tank without PCM. For the new tank, the optimal amount of PCM is obtained, based on which the increased absorption pressure could effectively accelerate the heat discharge and reaction rate during the absorption process. However, the increased inlet velocity of HTF has a limited improvement effect on heat transfer and reaction performance. Furthermore, on the PCM side of the tank, the addition of fins and increasing the thermal conductivity of PCM had little effect on the performance of the tank.

Thermodynamic and exergy analysis of a novel PEMFC-ORC-MH combined integrated energy system

Nowadays, Proton Exchange Membrane Fuel Cell (PEMFC) generates a large amount of heat in operation, resulting in energy waste. To improve energy utilization through waste heat recovery, a novel integrated energy system coupling with PEMFC, Organic Rankine Cycle (ORC) system and Metal Hydride (MH) hydrogen storage system was unprecedentedly presented and investigated. The ORC system utilizes the heat generated by the stack and further generates electric energy, while the MH system absorbs the heat in the exhaust steam of the ORC working medium and then desorbs hydrogen. Based on the above design, this study established the mathematical model of the system, and then analyzed the variation trends of system performance versus the stack current variation. Following that, this study investigated the effect of crucial parameters, including the inlet temperature for the stack cooling water, the superheat temperature, the saturation pressure, the condensation temperature, the pressure in MH tank and the hydrogen weight fraction, on the system performance. Results demonstrated that, when compared with that of the single PEMFC, the overall performance of the system significantly improves, and at the maximum power point of the system, the output power, electrical efficiency, energy efficiency and exergy efficiency rise by 15.0%, 4.3%, 14.1% and 4.9%, respectively. Besides, the simultaneous increase of the superheat temperature and saturation pressure can improve the electrical efficiency of the system without reducing the hydrogen desorption rate. Moreover, the higher hydrogen weight fraction and lower pressure in MH tank could improve the hydrogen desorption rate. Additionally, the system’s electrical efficiency and the hydrogen desorption rate are highly sensitive to the condensation temperature, and it is recommended that the condensation temperature be controlled within a reasonable range of 300 K–310 K. Present works perform a theoretical basis for the construction and performance optimization of this proposed system.

Evaluation of the Performance Degradation of a Metal Hydride Tank in a Real Fuel Cell Electric Vehicle

In a fuel cell electric vehicle (FCEV) powered by a metal hydride tank, the performance of the tank is an indicator of the overall health status, which is used to predict its behaviour and make appropriate energy management decisions. The aim of this paper is to investigate how to evaluate the effects of charge/discharge cycles on the performance of a commercial automotive metal hydride hydrogen storage system applied to a real FCEV. For this purpose, a mathematical model is proposed based on uncertain physical parameters that are identified using the stochastic particle swarm optimisation (PSO) algorithm combined with experimental measurements. The variation of these parameters allows an assessment of the degradation level of the tank’s performance on both the quantitative and qualitative aspects. Simulated results derived from the proposed model and experimental measurements were in good agreement, with a maximum relative error of less than 2%. The validated model was used to establish the correlations between the observed degradations in a hydride tank recovered from a real FCEV. The results obtained show that it is possible to predict tank degradations by developing laws of variation of these parameters as a function of the real conditions of the use of the FCEV (number of charging/discharging cycles, pressures, mass flow rates, temperatures).

A Triple Photoredox/Cobalt/Brønsted Acid Catalysis Enabling Markovnikov Hydroalkoxylation of Unactivated Alkenes.

We demonstrate Markovnikov hydroalkoxylation of unactivated alkenes using alcohols through a triple catalysis consisting of photoredox, cobalt, and Brønsted acid catalysts under visible light irradiation. The triple catalysis realizes three key elementary steps in a single catalytic cycle: (1) Co(III) hydride generation by photochemical reduction of Co(II) followed by protonation, (2) metal hydride hydrogen atom transfer (MHAT) of alkenes by Co(III) hydride, and (3) oxidation of the alkyl Co(III) complex to alkyl Co(IV). The precise control of protons and electrons by the three catalysts allows the elimination of strong acids and external reductants/oxidants that are required in the conventional methods.

Parametric and sensitivity analysis of metal hydride hydrogen storage systems for development of novel design charts

AbstractHydrogen storage is the biggest challenge towards the widespread utilization of hydrogen as an energy carrier. One of the methods is solid‐state storage of hydrogen in the metal hydride, which is safe, volumetrically efficient, and involves an optimal set of operating conditions. However, designing reactors for metal hydride storage involves much thermal management since the absorption and desorption are exothermic and endothermic reactions, respectively. Many optimization and simulations are involved before arriving at a suitable metal hydride reactor design for a particular application. This study focuses on developing easy‐to‐use design charts to evaluate reaction fractions inside the metal hydride bed for various combinations of parameters. First, the parameters affecting the reaction fraction are selected, and the range for each of these parameters is defined. The dependence of each parameter on the reaction fraction is analysed, maintaining the mean value of the remaining parameters. The LaNi5 is used as a metal hydride for this study. A two‐dimensional (2‐D) mathematical model is developed to evaluate the effect of these parameters on reaction fraction. Further, based on this detailed parametric study, a sensitivity analysis has been carried out to determine the most significant parameters. It was observed from this parametric and sensitivity analysis that among the considered parameters, the volume of the reactor (amount of hydrogen to be stored) and length to diameter ratio have a more dominant effect on the reaction fraction followed by supply pressure and thermal conductivity of metal hydride. However, the external temperature of heat transfer fluid (ie, the ambient temperature) does not significantly affect the reaction fraction. Hence, this parameter is assumed to be constant in developing design charts. Also, based on this analysis, the range of parameters is redefined for design charts. Further, this 2‐D mathematical model and parametric and sensitivity analysis are used to develop the design charts. These design charts use the most sensitive parameters and demonstrate the effect of all the other parameters on the reaction fraction. Finally, the method of using these design charts and their accuracy is explained for reaction fraction evaluation for a particular set of parameters. These charts are easy‐to‐use and accurate for the quick preliminary reaction fraction estimation for metal hydride hydrogen storage system.

Breaking the continuous hydride network in hydrogen-charged pure titanium to repair hydride–induced performance degradation by applying a pulsed electric current

Titanium readily reacts with hydrogen to form hydrides, which greatly deteriorates their mechanical properties. In particular, the continuous hydride network provides a path for crack initiation and propagation. In this study, the hydrogen–charged pure titanium with continuous hydride network were treated by electropulsing treatment and traditional heat treatment. It was found that the elongation of the hydrogen–charged pure titanium were effectively repaired after the electropulsing treatment, while the heat treatment failed. The recovery of elongation of the hydrogen–charged pure titanium can be attributed to the disintegration of the continuous hydride network and the decrease of hydrogen content after the electropulsing treatment. Due to the different electrical properties of the hydrides and the Ti-matrix, the current in hydrogen-charged pure titanium is not uniformly distributed, resulting in the decomposition of the continuous hydride network at lower than conventional tempering temperatures. This particular method can not only be used for the repair of hydride–induced embrittlement, but also can be extended to the optimization of thermo–hydrogen treatment of titanium alloys and the rapid hydrogen release of metal–hydride hydrogen storage materials.

Innovative battery thermal management system based on hydrogen storage in metal hydrides for fuel cell hybrid electric vehicles

This study proposes a new approach for dealing with the thermal management of batteries in fuel cell hybrid electric vehicles, by introducing a new concept of on-board energy storage system which integrates the battery pack with a metal hydride tank. The rationale behind this solution is to use the exothermic absorption and endothermic desorption processes of hydrogen in metal hydrides for heating and cooling the battery pack, respectively, thus ensuring an optimal thermal management control. An experimental investigation is carried out on a prototype in order to proof the concept and preliminary assess its feasibility for actual implementations. The results show that the system is capable to effectively control the temperature variations within the battery pack: for 1C and 1.5C constant-current discharge tests, a desorption of 30%–40% of hydrogen, over the total amount stored into the metal hydride tank of the system, allows the final average temperature of the battery pack to be around 15 °C lower than the one reached without thermal management. Moreover, it is found that the system is potentially capable of providing a suitable thermal management for more than four hours under realistic driving conditions. The proposed energy storage system also achieves inherently high gravimetric and volumetric energy densities, with theoretical values equal to 182 Wh/kg and 530 Wh/L, respectively. These estimates represent reference values for further design improvements.

Numerical investigation of heat and mass transfer during hydrogen desorption in a large-scale metal hydride reactor coupled to a phase change material with nano-oxide additives

For the object of reducing heat consumption in hydrogen metal hydride (MH) storage units during the discharging cycle, the nano-PCM (i.e. phase change material containing nano-oxides) strategy is adopted herein for accelerating the release of the latent heat (LH) stocked in the PCM to the MH. The process was assessed in a large-scale horizontal cylindrical reactor equipped with 4 PCM tubes distributed homogenously in the MH-bed. Mass and heat transfer were computationally analyzed in the diverse regions of the MH-nano-PCM system using a 2D numerical model developed with Fluent 15.0 CFD-software. Temporal temperature profiles (average and contours), MH-dehydrogenation efficiency, velocity contours and PCMs solidification rate were established in the presence (5% v/v) and absence of four types of nano-oxides (Al2O3, MgO, SnO2 and SiO2). Remarkable results were obtained. The nano-PCM system participated in the MH-discharging by providing latent heat (LH) and changing its physical phase. The MH was completely discharged within 700 s. Nano-oxides additions improved the solidification rate of the PCM (i.e. accelerating the release of the LH) by more 50%, with a strong dependency on the PCM-tubes position. The PCM-tube above the H2-charging pipe solidifies more quickly than the other tubes, probably to the gravitational effect. The outcomes of this research provide insight into the use of nano-PCMs as a thermal supplier in MH storage systems during the discharging cycle.

Pilot-scale hydrogen energy utilization system demonstration: A commercial building case study on on-site green hydrogen production and use

A demonstration of the Hydro Q-BiC®, i.e., a pilot-scale green hydrogen energy utilization system consisting of 64.75-kW photovoltaic (PV) panels, a 5-Nm3/h water electrolyzer, 40 Nm3 of metal hydride hydrogen storage, 14-kW fuel cells, and 20-kW/20-kWh Li-ion batteries, is discussed here. We set up our hydrogen system in front of a market administration building with demands that differ from those of a typical business building. The purpose of this study is to demonstrate the practicability of the green hydrogen system. The demonstration tests include 24-h experiments with various weather conditions: clear, cloudy, and clear to rainy; the CO2 reduction capability evaluation is based on the results. In all cases, the CO2 reduction capability is shown to be better than that of the PV-only system. However, the utilization of grid power for hydrogen production is proven to be of concern in the event of drastic and unexpected changes in weather conditions. Simulating annual CO2 emissions indicates that the Hydro Q-BiC® can reduce emissions by more than 50%. We believe our findings can develop the practical application of hydrogen energy systems for buildings.

Transient simulation studies on a metal hydride based hydrogen storage reactor with longitudinal fins

In this study, a 50 kg LaNi5 based shell and tube type metal hydride hydrogen storage reactor is investigated. The design process for the reactor is presented and its performance analysis is carried out numerically. The metal hydride is filled in the tubes while the shell side houses the heat transfer fluid. Each of the metal hydride tubes is equipped with fins connected to a longitudinal array of concentric cylinders for support and for ensuring uniform distribution of alloy powder, which is a challenge in case of large reactors. The number of tubes MH tubes which is seven in the present case was selected on the basis of highest heat transfer capacity per unit system weight. The reactor performance was simulated under varying operating conditions. It was observed that reactor performance was quiet promising at a moderate supply pressure of 35 bar and a heat transfer fluid flow rate of as low as 30 lpm. Any increase in flow rate does not alter the reactor performance significantly. Initial bed temperature did not have any significant effect on the system performance. Thermal resistance network analysis established that heat transfer was primarily limited by conduction.

Capturing multiphysics effects in hydride moderated microreactors using MARM

High temperature hydrides are being considered as neutron moderators for LEU microreactor systems due to their ability for creating a compact core with minimum loading of a fissile material. Under the influence of a temperature gradient, hydrogen in metal hydrides is prone to diffusion. This migration of hydrogen during the reactor operation results in local changes in moderator material properties; such as changes in neutron cross sections leading to changes in power and temperature distributions. High fidelity multiphysics modeling is required to properly understand the reactor dynamics during its operation. MCNP, a Monte-Carlo based particle transport code, and Abaqus, a finite-element engineering simulation software, are used to develop a multiphysics framework named MARM for high temperature reactor analysis. MARM is short for MCNP and Abaqus based Reactor Multiphysics software package being developed at the Los Alamos National Laboratory. This suite of codes is aimed to enable multiphysics analysis for full core applications by incorporating neutronics, heat transfer, and mass diffusion solutions. This paper demonstrates the significance of capturing multiphysics effects in a hydride-moderated reactor system. This paper also provides an outline of MARM multiphysics development and its future plans.

Multi-field coupled modeling of metal hydride hydrogen storage: A resistance atlas for H2 absorption reaction and heat-mass transport

Metal hydride hydrogen storage (MHHS) is an efficient technology to raise the hydrogen storage level. Currently, insight into the interaction between reaction and heat-mass transfer to achieve excellent storage performance is still a pressing issue. Therefore, in a specific example of LaNi5, this work adopted a transient multi-field coupling model for the hydrogen storage reactor to investigate the reaction-transport resistance characteristics, as well as the reaction heat management and enhancement strategy. According to the investigation, the operating parameters (such as temperature, pressure and porosity) have significant influences on the absorption reaction evolution. When the temperature increases from 55 °C to 65 °C, the saturated hydrogen absorption capacity decreases from 5.28 to 1.76. When the pressure decreases from 1.6 MPa to 0.4 MPa, the reaction evolution time will increase from 42.8 min to 121.6 min, the growth rate was 64.8%. Large porosity also contributes to reaction rate and reduces the average temperature of the reaction bed (RB). With external cooling measures, the absorption evolution can be significantly boosted. In addition, a general resistance atlas capable of clarifying the reaction and heat-mass transport characteristic is drawn. According to the characters of reaction resistance Rr, heat resistance Rh (including conduction R(lλ) and convection R(1h)) and flow resistance (Rf), the hydrogen absorption evolution is distinctly divided into four zones, among which the Rh dominating zones is the most remarkable that means the heat management and heat transfer enhancement still retain lots of margin for raising the H2 absorption evolution. The performance tuning limit is also presented in the atlas. Currently, focusing on internal-conduction and external-convection enhancement for the reactor design is quite effective and efficient in improving MHHS performance.

Development of a plug-in fuel cell electric scooter with thermally integrated storage system based on hydrogen in metal hydrides and battery pack

The thermal management of lithium-ion batteries in hybrid electric vehicles is a key issue, since operating temperatures can greatly affect their performance and life. A hybrid energy storage system, composed by the integration of a battery pack with a metal hydride-based hydrogen storage system, might be a promising solution, since it allows to efficiently exploit the endothermic desorption process of hydrogen in metal hydrides to perform the thermal management of the battery pack. In this work, starting from a battery electric scooter, a new fuel cell/battery hybrid powertrain is designed, based on the simulation results of a vehicle dynamic model that evaluates power and energy requirements on a standard driving cycle. Thus, the design of an original hybrid energy storage system for a plug-in fuel cell electric scooter is proposed, and its prototype development is presented. To this aim, the battery pack thermal power profile is retrieved from vehicle simulation, and the integrated metal hydride tank is sized in such a way to ensure a suitable thermal management. The conceived storage solution replaces the conventional battery pack of the vehicle. This leads to a significant enhancement of the on-board gravimetric and volumetric energy densities, with clear advantages on the achievable driving range. The working principle of the novel storage system and its integration within the powertrain of the vehicle are also discussed.

Multi-Objective Optimization of Metal Hydride Hydrogen Storage Tank with Phase Change Material

Multi-Objective Optimization of Metal Hydride Hydrogen Storage Tank with Phase Change Material

Design of a hydrogen-powered bicycle for sustainable mobility

Hydrogen-powered vehicles are emerging as a key source for a clean and sustainable mobility scenario. In particular, hydrogen technologies have a great potential for light mobility in urban areas, where traffic congestion may cause very high levels of local pollution. In this context, hybrid fuel cell/battery vehicles represent a promising solution, since they allow for extended driving range and short recharge time, which are two of the major concerns related to electric propulsion, in general. In this work, a new plug-in fuel cell electric bicycle concept is presented, where the on-board energy storage is realized by means of an innovative system integrating a battery pack with a metal hydride hydrogen tank. This solution allows to achieve very high performance in terms of riding range, which are unattainable with traditional battery electric bicycles. In particular, the hybrid energy storage system is conceived to provide an optimal thermal management of the two integrated components. The proposed design is developed on the basis of typical duty cycles acquired during on-road measurements. A prototype of the bicycle is then realized and bench-tested in order to assess design consistency and to evaluate its performances. The results show that the riding range of the new hydrogen-fuelled bicycle is about three times higher than the one for a similar electric bicycle.

Pilot autonomous hybrid hydrogen refueling station utilizing a metal hydride compressor covering local transportation needs

The need for decreasing carbon emissions in the transportation sector in order to meet the targets of the European Union by 2030, inevitably leads to the large scale adoption of cleaner alternatives. Hydrogen fueled vehicles could possibly provide one such alternative, if we could assume that the necessary infrastructure would be widely available throughout Europe. Already, the European Union has committed to the construction of a significant number of Hydrogen Refueling Stations (HRS) by year 2025 and in view of that, there is a need of developing suitable configurations for the production, compression, storage and dispensing of green hydrogen to hydrogen fueled vehicles. This work presents an autonomous hybrid system which produces green hydrogen by PV- powered water electrolysis (PEM), which is subsequently compressed by a novel metal hydride hydrogen compressor to pressures up to 200 bar. This pilot HRS will meet the daily demand of 2 scooters and a golf cart which have been transformed, in order for their electric motor to be powered by a hydrogen fuel cell instead of a battery. An important element of the work which is presented, revolves around the integration of the metal hydride compressor with the rest of the system, and how this integration won’t hinder its functionality. The complete system design and layout is presented, while the results from the system operation could give a good idea regarding the optimal system sizing for similar large scale applications.

Parametric optimization of coupled fin-metal foam metal hydride bed towards enhanced hydrogen absorption performance of metal hydride hydrogen storage device

The optimal arrangement form of a certain amount of high thermal conductivity materials for getting the best heat transfer rate and uniformity in metal hydride reactor needs to be investigated. In this work, the coupled fin-metal foam metal hydride reactor was proposed and investigated using a 3D multi-physical model. Thermal resistance analysis showed that the thermal resistance of fin-metal foam reactor was below 0.0099K/W, which was lower than that of metal foam reactor of 0.01035K/W and fin reactor of 0.0235K/W. Furthermore, Genetic Algorithm was used to optimize the proportions of fin and metal foam in fin-metal foam reactors under a certain amount of high thermal conductivity materials. The comparison results showed that the charging time for 90% saturation of optimized fin-metal foam reactor was decreased by 6.9% and 38% compared with metal foam reactor and fin reactor, respectively. It was indicated that the optimal fin volume ratios of optimized fin-metal foam reactors maintained around 0.4 under different volumetric fractions of high thermal conductivity materials. Besides, considering the trade-off between hydrogen storage rate and hydrogen storage capacity, the optimal volumetric fraction of high thermal conductivity materials for obtaining the best comprehensive hydrogen absorption performance of optimized fin-metal foam reactor approximately equaled 0.08.