High Power Generation Research Articles

(Invited) High Performing Fuel Cell Stack and Systems

PowerCellGroup has worked in the field of fuel cell systems and fuel cell stacks for more than 25 years. The development of both systems and stacks have gone hand in hand and have been important to reach the targets for both.The fuel cell stack currently offered to the market has been developed during the last 10 years. Starting out with focus on passenger vehicles to achieve the requirements on power density. The second step the development was tailored to meet the demands from heavy-duty usage, that requires high efficiency at high power output and longer durability as well as increased operating temperature. This second stage unlocked the usage of fuel cell in more applications like, stationary high-power generation, off-rad machinery and lately the aviation sector.The later years the implementation of hydrogen and fuel cell on the market have accelerated and more commercial usage putting larger requirement on higher power, longer durability, higher operating temperatures etc. For example, how to install several MW into marine vessels.The third phase that we are now entering is to take the fuel cell to the next level, to the sky. Improving power density towards 5-6 kW/kg, operating temperature up to 120°C, and larger stack sizes 300 kW scalable to about 1 MW this to meet the higher power demand by aircraft. PowerCell is on a good track in all these aspects to be ready for the future. In this talk will be about how we constantly improving and challenging the fuel cell system and fuel cell stacks to be used in commercial operation.

Self-powered ocean buoy using a disk-type triboelectric nanogenerator with a mechanical frequency regulator

Triboelectric nanogenerator (TENG) systems have been demonstrated to generate power with high density. However, the electrical output power obtained from wave energy harvesting using TENG systems is typically limited to several milliwatts. To address this limitation and support various ocean buoy systems, an efficient method to scale-up TENG systems is required. In this paper, we present a self-powered ocean buoy (SPOB) incorporating a disk-type, soft-contact, mechanical frequency regulator TENG (DSMFR-TENG). The mechanical frequency regulator (MFR) enables the conversion of low-frequency wave energy to high-speed mechanical rotation, facilitating high power generation with the disk-type TENG. The SPOB was tested in a wave tank, reaching a peak power output of 470 mW and an average power output of 130 mW after the MFR released the rotational energy. To further enhance the functionality of the buoy, the DSMFR-TENG and a microcontroller, temperature sensor, and acoustic transmitter were integrated with the SPOB. The acoustic transmitter successfully transmitted signals 7, 23, and 30 times over a one-minute period at wave frequencies of 0.33 Hz, 0.5 Hz, and 1 Hz, respectively, thereby demonstrating the power supply capability of the TENG system for ocean buoys.

Characterization of Ca-doped YCoO3 Perovskite-type oxide as cathode for solid oxide fuel cells

Solid oxide fuel cell (SOFC) uses solid oxide as an electrolyte and has a high-power generation efficiency. One of the major problems in the development of SOFC is the side reaction that occurs at the interface between the electrode and the electrolyte. (Y, Ca)CoO[Formula: see text] materials were evaluated as a new air electrode material to replace the conventional (La, Sr)CoO3 materials. Y[Formula: see text]Ca[Formula: see text]CoO[Formula: see text] has good compatibility with Y-stabilized ZrO2 (YSZ) electrolyte. In addition, the power generation performance was equal to or better than the conventional SOFC cells.

Semitransparent Organic Solar Cells with Homogeneous Transmission and Colorful Reflection Enabled by an ITO-Free Microcavity Architecture.

Semitransparent organic photovoltaics (ST-OPVs), owing to the merits of high power generation, thermal insulation, and aesthetic features, have become a promising candidate for intellectual building- integrated photovoltaic windows. However, the traditional optical evaluation only focuses on the transmission properties and ignores the reflection behaviors. And the lack of quantitative descriptions for array appearance hinders implementation of ST-OPV based large-area modules. To tackle with these issues, an indium tin oxide (ITO)-free optical microcavity architecture into ST-OPVs for achieving high homogeneity in transmittance with controllable reflective appearances through tunning the thickness of individual component layers is introduced. A set of parameters based on optical characteristics of sub-units to provide a quantitative description for the transmittance brightness, transmissive and reflective color purity, and versatility of optical arrays, is further proposed. The optical simulations reveal that reflection modulation from blue to red colors can be realized for devices based on various bulk-heterojunction material systems through regulating the thickness of active layers and antireflection coatings. This work offers a viable design strategy for ST-OPVs toward applications in next-generation smart photovoltaic windows.

Highly Stretchable, Knittable, Wearable Fiberform Hydrovoltaic Generators Driven by Water Transpiration for Portable Self-Power Supply and Self-Powered Strain Sensor.

The development of excellently stretchable, highly mobile, and sustainable power supplies is of great importance for self-power wearable electronics. Transpiration-driven hydrovoltaic power generator (HPG) has been demonstrated to be a promising energy harvesting strategy with the advantages of negative heat and zero-carbon emissions. Herein, this work demonstrates a fiber-based stretchable HPG with the advantages of high output, portability, knittability, and sustainable power generation. Based on the functionalized micro-nano water diffusion channels constructed by the discarded mask straps (MSs) and oxidation-treated carbon nanomaterials, the applied water can continuously produce electricity during the spontaneous flow and diffusion. Experimentally, when a tiny 0.1mL of water encounters one end of the proposed HPG, the centimeter-length device can yield a peak voltage of 0.43V, peak current of 29.5µA, and energy density of 5.833mWhcm-3. By efficiently integrating multiple power generation units, sufficient output power can be provided to drive commercial electronic devices even in the stretched state. Furthermore, due to the reversibility of the electrical output during dynamic stretching-releasing, it can passively convert physiological activities and motion behaviors into quantifiable and processable current signals, opening up HPG's application in the field of self-powered wearable sensing.

Biomass-derived multifunctional nanoscale carbon fibers toward fire warning sensors, supercapacitors and moist-electric generators

Nowadays, great effort has been devoted to designing biomass-derived nanoscale carbon fibers with controllable fibrous morphology, high conductivity, big specific surface area and multifunctional characteristics. Herein, a green and renewable strategy is performed to prepare the biomass-based nanoscale carbon fibers for fire warning sensor, supercapacitor and moist-electric generator. This preparation strategy thoroughly gets over the dependence of petroleum-based polymeride, and effectually improves the energy storage capacity, sensing sensitivity, humidity power generation efficiency of the obtaining biomass-based carbon nanofibers. Without the introduction of any active components or pseudocapacitive materials, the specific capacitance and energy density for biomass-based nanoscale carbon fibers achieve 143.58 F/g and 19.9 Wh/kg, severally. The biomass-based fire sensor displays excellent fire resistance, stability, and flame sensitivity with a response time of 2 s. Furthermore, the biomass-based moist-electric generator shows high power generation efficiency. The output voltage and current of five series connected and parallel-connected biomass-based moist-electric generators reaches 4.30 V and 43 μA, respectively. Notably, as the number of biomass-based moist-electric generators in series or parallel increases, the overall output voltage and current of the device system have a linear relationship. This work proposes a self-powered fire prediction system based on nanoscale carbon fibers that integrates sensing, power generation, and energy storage functions.

A Compact High Gain Pulse Power Generator Employed With Magnetic Pulse Compression and Push-Pull Charger for Applications in Dielectric Barrier Discharge

A Compact High Gain Pulse Power Generator Employed With Magnetic Pulse Compression and Push-Pull Charger for Applications in Dielectric Barrier Discharge

Dynamic modeling and stability analysis of parafoil traction cable for high altitude wind power generation

In high altitude wind parafoil power generation (HAWPG), parafoil traction cable plays an important role. The cable, which is stretched by the parafoil, is prone to excite vibration even under small disturbances, which affects the stability of the entire HAWPG system. In view of this problem, this paper establishes parafoil traction cable dynamic model and analyzes the unstable regions of the cable parametrically excited vibration. The cable dynamic model, which has axial time-varying velocity and tension, is established based on Hamilton principle. Based on the cable ordinary differential equation, a second-order cable Mathieu–Hill differential equation can be obtained. Then, solve the vibration instability regions caused by changing parameters, the boundaries of different regions on the parameter plane can be directly determined by constructing the periodic solution. Finally, numerical examples and phase portraits are provided to verify the proposed method. The parameters, which includes the cable material properties, length and axial velocity, determined the boundedness of cable vibration. Therefore, the parafoil traction force on the cable should be set appropriately when determining the cable material properties to avoid the unstable vibration.

A high-power and high-efficiency mini generator for scavenging energy from human foot movement

A high-power and high-efficiency mini generator for scavenging energy from human foot movement

Editorial

The editorial of Thermal Engineering of this issue continues the discussion on scientific research needs in vital areas in which thermal engineering has important participation. The main goal is to motivate the readers, within their specialties, to identify possible subjects for their future research. The naval sector dominates global commerce totalizing more than 80% of volumes transported]. Heavy fuel oil and marine gas oil are the most utilized fuels and make up 2 to 3% of the human produced CO2 dumped in the atmosphere. Until the year 2050, the International Maritime Organization (IMO) is committed to a 50% reduction of ship greenhouse gases (GHG) emissions with predicted full elimination by 2100. However, military ships are expected to require ten times more electric power than current navy vessels. As a result, the all-electric military ship initiative depends heavily on scientific research and development of environmentally benign high density power generation systems. In that scenario, fuel cells bring a possible path to problem solution. The low-temperature Polymer Electrolyte Membrane Fuel Cell (PEMFC) is recognized to be the most popular FC. Although PEMFC has been used in transportation (e.g., vehicular, ships), PEMFC general use still brings several concerns, due to some shortcomings (e.g., water management, platinum content, Nafion membrane high cost, free energy demanding H2 availability). In parallel, there has been a demand to develop innovative and environmentally correct technologies for alternative energy sources to replace traditional fossil and nuclear sources, including the naval sector, for quite a while, and this need is current, and the main hurdles to overcome are the generation and storage of renewable energy in a technically and economically viable way. The mission of Thermal Engineering is to document the scientific progress in areas related to thermal engineering (e.g., energy, oil and renewable fuels). We are confident that we will continue to receive articles’ submissions that contribute to the progress of science.

Core nuclear design and heat transfer analysis of a megawatt-level SiC coated particle based vehicular micro reactor

As a versatile and diversified source of new energy, transportable micro reactors can offer high flexibility and the ability to provide power services even in remote areas. When utilizing coated fuel particles and supercritical carbon dioxide (S-CO2) coolant, the transportable micro reactor core achieves exceptional inherent safety and high power generation efficiency, rendering it incredibly competitive within the nuclear market. The Vehicular Micro Reactor (VMR) previously investigated is an integrated micro-reactor cooled by S-CO2, which employs TRistructural ISOtropic (TRISO) fuel particles dispersed in a conventional graphite matrix to generate 5 MW of power output. However, its drawback lies in the low fuel loading capacity. In recent year, the application of high-strength SiC materials in the field of nuclear energy has been developing continuously. In this paper, a new type of double-layered SiC coated fuel particle is designed, based on which a SiC-based Vehicular Micro Reactor (SVMR) is proposed and explored. It represents an improved design of VMR, with the main difference being its utilization of SiC as a matrix and filling by the two-layered SiC-coated fuel particle to achieve higher fuel loading than the VMR. In this paper, both the neutronic and heat transfer characteristics of the SVMR are discussed. The neutronic simulation is conducted using SCALE code based on Monte Carlo method, the module KENO IV was used to analyze the effective neutron multiplication factor (keff), and SCALE/TRITON (Transport Rigor Implemented with Time-Dependent Operation for Neutronic Depletion) coupled by 2-D radiation transport code NEWT and ORIGEN for burn-up calculation. By optimizing the assembly size and SiC-coated fuel particle size, the SVMR core achieves high fuel loading capacity and superior fuel utilization efficiency. The results of the heat transfer analysis also demonstrate that the SVMR core, which is entirely SiC-based, exhibits exceptional heat transfer capability. The excellent neutron economy and inherent safety make SVMR a more competitive micro reactor concept.

High-Power, High-Purity HG0n Hermite–Gaussian Laser Beam Generation in Cascaded Large Aspect Ratio Slabs

High-power, high-purity, nanosecond (ns) one-dimensional HG0n laser beams are proposed and demonstrated by using Nd:YAG cascaded slabs with a large aspect ratio. The HG0n laser beams are generated by adjusting the pump distribution, the intracavity apertures, and the tilt angle of the output coupler (OC). By controlling the gain and loss of HG0n modes of different orders, the high-purity, one-dimensional, high-order HG0n laser beams with orders 1 to 9 (HG01 to HG09) are produced, and their beam quality factors M2 align well with the theoretical predictions. Meanwhile, the large aspect ratio slab provides an ideal amplifier for the strip-shaped HG0n laser beams, and further power scaling is achieved by seeding the generated HG0n laser beams into an amplifier with an identical slab module. For the HG09 mode, the average power is amplified from 289 mW to 4.73 W with 294 ns pulse width, corresponding to a peak power of 32 kW. Moreover, above 5 W average power is achieved for all HG01 to HG08 modes. Hopefully, this scheme provides a solution for high-power and high-purity HG0n laser beam generation based on the slab-shaped configuration.

Direct CH4–CO2 solid oxide fuel cells combined with Li-doped perovskite dry reforming catalysts for high efficiency power generation

Direct CH4–CO2 solid oxide fuel cells (SOFC) have attracted considerable attention due to their potential for high-efficiency power generation with low environmental impact. However, carbon deposition on Ni-based cermet anodes remains a critical challenge, leading to performance degradation. In this study, we propose a novel approach to address this issue by using a Li-doped perovskite, (La0.75Sr0.25)0.95Li0.1Cr0.5Fe0.4Ni0.1O3-δ (LSLCFN), as an exsolution system and a dry reforming catalyst for SOFCs. The LSLCFN catalyst exhibits enhanced carbon dioxide adsorption capacity, effectively reducing carbon deposition on the anode surface. In addition, the incorporation of Ni–Fe alloy nanoparticles facilitates dissolution in a reducing atmosphere and exhibits remarkable stability in the presence of carbon dioxide. Anode-supported single cells incorporating a LSLCFN-Ce0.9Gd0.1O2–δ(LSLCFN-GDC) composite as the anode active reforming layer exhibit excellent electrochemical performance when operated with both H2 and CH4–CO2 fuels. The peak power densities reach 904.86 and 825.37 mW cm−2 at 800 °C, respectively. Furthermore, the LSLCFN-GDC reforming layer maintains stable performance during the dry reforming of a 50%CH4–50%CO2 fuel mixture for 100 h at 700 °C, with negligible carbon deposition. These results highlight the effectiveness of employing a dry reforming catalyst to enhance CH4–CO2 reforming and optimize electrochemical performance for efficient energy conversion in SOFCs.

Achieving Solar-Thermal-Electro Integration Evaporator Nine-Grid Array with Asymmetric Strategy for Simultaneous Harvesting Clean Water and Electricity.

Water evaporation is a ubiquitous and spontaneous phase transition process. The utilization of solar-driven interface water evaporation that simultaneously obtains clean water and power generation can effectively alleviate people's concerns about fresh water and energy shortages. However, it remains a great challenge to efficiently integrate the required functions into the same device to reduce the complexity of the system and alleviate its dependence on solar energy to achieve full-time operation. In this work, a multifunctional device based on reduced graphene oxide (RGO)/Mn3 O4 /Al2 O3 composite nanomaterials is realized by an asymmetric strategy for effective solar-thermal-electro integration that can induce power generation by water evaporation in the presence/absence of light. Under one sun irradiation, the solar-driven evaporation rate and output voltage are 1.74kgm-2 h-1 and 0.778V, respectively. More strikingly, the nine-grid evaporation/power generation array integrated with multiple devices in series has the advantages of small volume, large evaporation area, and high power generation, and can light up light-emitting diodes (LEDs), providing the possibility for large-scale production and application. Based on the high photothermal conversion efficiency and power production capacity of the RGO/Mn3 O4 /Al2 O3 composite evaporation/generator, it will be a promising energy conversion device for future sustainable energy development and applications.

Three‐Dimensional Printing of High‐Performance Moisture Power Generators

AbstractWater‐enabled electricity generation technologies that are highly accessible and fundamentally clean are promising for next‐generation green energy. However, the challenge of scalability in both material processing and device fabrication greatly limits their practical applications. A high‐performance polyelectrolyte moist‐electric generator (MEG), which can be directly 3D printed for massive production and efficient integration, is reported. The printed MEG (p‐MEG) generates a high open‐circuit voltage of 0.8 V and a short‐circuit‐current density of 0.12 mA cm−2 by actively harvesting moisture from humid conditions. The synergistic effects of moisture gradient, ionic concentration gradient, and ion diffusion gradient, which remarkably enhance the driving force to separate ion pairs and notably facilitate the directional ion transport, are responsible for the high power generation performance of p‐MEG, as further backed up by in situ ion dynamics investigations and molecular simulations. When connected in serial and parallel, hundreds of p‐MEGs can deliver a high voltage of more than 180 V and a current of more than 1 mA. A constructed “moisture‐powered cup lamp” that lights up for hours further demonstrates the practicability of p‐MEG. This work provides a feasible and scalable 3D printing approach for the next‐generation environment‐adaptive self‐powered system.

Grain refinement and polarization enhancement synergistically triggered NBT-based piezoceramics enabling sustainable high power generation

Lead-free piezoelectric energy harvesters (PEHs) with long-term stable power generation capability is an important solution for realizing reliable self-power supply of microelectronic devices such as wireless sensors. As the core of PEHs, piezoceramics with practical value require not only high figure of merit (FOM) to achieve high power generation, but also strong fracture toughness (KIC) to prevent the fracture failure caused by long-term cyclic vibration, which poses a challenge to the material design. To address these concerns, K0.5Bi0.5TiO3 was rationally introduced into Na0.5Bi0.5TiO3 matrix, and the synergistic effect of grain refinement and polarization enhancement was realized through composition design and grain size regulation to obtain excellent performance with KIC of 1.57 MPa·m1/2 and FOM of 1.94 × 10−12 m2/N. The cantilever beam-type PEH with the optimal sample achieved a high output power density of 395.5 μw/cm3, in particular, under different acceleration conditions (1g-3g), after 106 cycles, the PEH can still maintain a stable power generation output, showing a super-strong service capability. This work not only provides a class of NBT-based piezoceramics with excellent electromechanical properties, but more importantly, the design strategy associated with double synergy effect is expected to be extended to the construction of more high-quality lead-free piezoelectric devices.

Thermodynamic analysis and comparison of four type CBC-ORC energy systems with regenerator using improved lunar regolith for heat storage applied to lunar base

Closed Brayton cycle (CBC)-organic Rankine cycle (ORC) system is an important option for lunar base energy system. In order to deeply explore the potential of CBC-ORC applications at lunar base, the impact of different system constructions on system performance needs to be evaluated. This paper establishes four types CBC-ORC mathematical model with different position of regenerator, and evaluates the daytime and nighttime operation characteristics of the regenerators, including thermal efficiency, thermal efficiency and power generation. The results show that the CBC regenerator can significantly improve the thermal efficiency of the system during the lunar daytime, with an increase of 15 %. However, ORC regenerator has limited improvement on system performance (only 4.28 %). In addition, the CBC regenerator can reduce the heat exchange area of solar trough collector and radiator by 60.3 % and 57.94 %, respectively. The CBC regenerator can balance the exergy destruction of each equipment, especially the evaporator. Compared with the energy system without CBC regenerator, its exergy destruction is reduced by 58 %. In summary, different demands correspond to different energy systems. Type 4 should be selected when the system is affected by limited space, high energy conversion efficiency is accomplished in limited space. If it is only to achieve high power generation, Type 3 is the best choice for the lunar base.

Application study of the power control system for air-cooled proton exchange membrane fuel cell based on fuzzy adaptive with heuristic adaptive period strategy

As a zero-emission, non-polluting power generation device, hydrogen fuel cells are of great interest to the global industry with the advantages of high-power generation efficiency, wide source, and wide application scenarios. Influenced by various factors, it leads to a complex fuel cell control system and unstable output characteristics, which is one of the difficulties in the current technology development. In this section, an embedded power control system according to an STM32 microcontroller is developed to improve the steady-state characteristics of cathode open air-cooled fuel cell (PEMFC), and a fuzzy adaptive PID control algorithm according to the heuristic adaptive strategy of time interval is proposed. The control system achieves real-time detection of operating status. It maintains the stable output of cathode open air-cooled PEMFC by predicting vehicle speed in real-time to precisely control the hydrogen supply and external additional fans to control the operating temperature by the control strategy.

Numerical Simulation of Paper-Based Flow Cells during Dynamic Infiltration Phase

Microfluidic electrochemical cells are increasingly being used as power sources for energizing portable electronic devices [1]. Of particular interest is the capillary-driven flow cells because they do not need any type of micropump to establish the flow. In a recent work [2], we developed a general, robust mathematical/numerical model for designing capillary-driven, paper-based, microfluidic flow cells. The model was validated against experimental data available for a novel single-use microfluidic flow cell of this nature called PowerPAD [3]. This flow cell is activated by a drop of water when poured on its sample pad. After dissolving the solid electrolytes stored below the sample pad, the liquid electrolytes produced this way infiltrate the porous electrodes before entering the cellulosic absorbent pad situated below the porous electrodes. Soon after entering the pad, they start flowing in the lateral direction until they are brought into direct contact with each other (at some point in time) so that the electrochemical reactions can take place at the electrodes. The two liquids then continue flowing co-laminarly until the pad becomes fully-saturated and the flow rate drops to zero. The experimental data reported by the inventors of the PowerPAD actually correspond to the fully-saturated case [3]. (Under these conditions the cell works like an ordinary battery when connected to an external load.) They demonstrated that, dependent on the thickness of the absorbent pad, the cell can generate electricity for roughly an hour. In [2], we showed that, for a given electrode, by modifying the microstructure of its absorbent pad (e.g., its porosity or pore-size) and/or its flow structure the runtime of the cell can be extended to roughly three hours so that it can be used for energizing certain portable electronic devices. However, there are other prospective applications in which the power might be needed for merely a few seconds [4]. Remote sensors used for measuring/reporting the pH of acid rains belong to this category. PowerPAD can be used for such short-lived applications, but the mathematical model presented in [2] has to be refined to simulate power generation during the dynamic infiltration process, which is the objective of the present work. As the first step, Darcy’s equation is solved numerically to find the bulk velocity from which the Reynolds number is obtained and used to calculate the mass-transfer coefficient. More importantly, the Richards equations is solved numerically to find the time-dependent saturation field, S(t), which is needed for calculating the mass-transfer coefficient during the infiltration process. Here, the empirical correlation proposed by Barton and Brushett [5] for the Sherwood number (Sh) is modified to incorporate a diffusion-limited term which varies linearly with the saturation field, S(x,y,t); that is: where Re is the Reynolds number and Sc is the Schmidt number. Figure 1a shows the two-dimensional model of PowerPAD used for the simulations, which were performed using the finite-element software package COMSOL; see [2] for the details. According to the imbibition results obtained for the 4h-PAD system [3], the cell is predicted to start generating electricity after t = 0.33 s; see Fig. 1b. The system, however, needs roughly t = 20 s to become fully-saturated. Figure 1c shows the polarization curves for the 4h-PAD system at discrete times, whereas Fig. 1d shows variation of the maximum power as a function of time, up to the fully-saturated time. In these figures the discrete times (5.2, 8, 12, and 20 s) correspond, respectively, to the flow rates 11, 4.5, 0.4, and 0.01 mm3/s. According to Fig. 1d, during the transient phase the maximum power is roughly 50% larger than that for the fully-saturated case. The higher power generation during this initial infiltration process is attributed to the bulk fluid flow through the porous electrodes implying that the mass-transfer coefficients are improved through Re and Sc.

Oxygen Ion Conduction Property of Solid Oxide Membrane Based on Multi-scale Analysis

In recent years, various environmental problems such as rising temperature, droughts, and extreme weather events have become more serious in many parts of the world because of global warming. One of the causes of the global warming is an increase in emissions of greenhouse gases such as CO2, CH4, and N2O, those are emitted during a combustion of fossil fuels such as coal, oil, and natural gas in thermal power generation. As energy consumption accelerates year by year, the depletion of fossil fuels is also becoming an issue. Therefore, hydrogen energy is attracting attention. Hydrogen is known as a clean energy because it reacts with oxygen to produce only water and chemical energy.Fuel cells are attracting attention as a new power generation device that produces electricity from hydrogen energy. Fuel cells generate electricity directly through chemical reactions, resulting in minimal power generation loss from energy conversion. Solid oxide fuel cells (SOFC), in which solid oxide electrolyte membrane (SOEM) is used as the electrolyte membrane, have particularly high-power generation efficiency. On the other hand, the operating temperature of SOFCs is extremely high (over 1000 K), which accelerates degradation of SOEM. Therefore, it is necessary to lower the operating temperature from high to medium (about 700 K) while maintaining high power generation efficiency.To solve this problem, we focus on dual-phasing and nano-structuring of SOEMs. Previous studies of SOEM have shown that dual-phase membranes have better ion transport performance than a single-phase membrane. For example, a dual-phase SOEM is composed of SSC (SrSc0.1Co0.9O3-d) with perovskite structure and SDC (Sm0.2Ce0.8O2-d) with fluorite structure. One the other hand, nano-structuring are nano-thin film and nano-crystalline. Nano-thin film is a method of forming an electrolyte film of several μm by layering nano-films of several nm in size. Nano-crystalline is a method to reduce a crystal size to several tens of nanometers. By these nano structures, the resistance of ion conduction is reduced, and ion conductivity is improved.However, the number of interfaces in dual-phase SOEM and nano structured membrane is expected to increase. Previous studies have reported a decrease in ion conductivity near the interface between different structures of membrane. This decrease in ion conductivity at the interface is caused by an increase in the energy barrier as the conduction path passes through the interface. The correlation between the reduction of ion conductivity and nano structures in membrane has not been clarified clearly.In this study, we analyze the mechanism of oxygen ion conductivity reduction near the interface by numerical simulations. Molecular simulations are performed to build up information by multi-scale analysis. Specifically, density functional theory (DFT), molecular dynamics (MD), and kinetic Monte Carlo (kMC) are performed in a bottom-up manner. First, MD simulations were performed using a potential model constructed from the energy states in the atomic arrangement at the interface obtained by DFT. We analyzed the ion conductivity at the interface and its crystal size dependence. We also create a hopping model of oxygen ions moving from site to site for kMC simulations. Next, kMC simulations are performed to analyze the oxygen ion conductivity in the dual-phase SOEM including interface, on a time and spatial scale similar to that of a real SOEMs.In this presentation, we report on the results of MD simulation. A dual-phase SOEM model consisting of SSC and SDC was used as the simulation model (Fig.1(a)). The diffusion coefficient of oxygen ions was obtained as an indicator of ionic conductivity. Because the ionic conductivity is determined by the balance between the energy barrier of the conduction path and the kinetic energy of the ions involved in ionic conduction. In this study, the activation energy for the diffusion was calculated as the energy barrier. The activation energy was estimated from Arrhenius relation of diffusion coefficient. The number of unit cells in the dual-phase SOEM model was varied to change the crystal size. As a result, both the diffusion coefficient and activation energy increase as the crystal size of SSC increases. On the other hand, as the crystal size of SDC increases, although the diffusion coefficient decreases, the activation energy increases (Fig.1(b)). These results show the dependence of the diffusion coefficient and activation energy on the crystal size in a dual-phase SOEM. Figure 1