Electrolyte Tubes Research Articles

Experimental determination of stray currents in parallel operated cells exemplified on alkaline water electrolysis

Avoiding undesired electric field-driven cell-to-cell ion conduction is a common issue in electrochemical bipolar stacks affecting many processes such as alkaline water electrolysis, chlor-alkali electrolysis, and redox flow batteries. In bipolar stack systems, they are known as ionic shunt or stray currents and flow alongside a cell stack through the electrolyte manifolds bypassing the bipolar plates. A similar phenomenon occurs if multiple single cells are operated in parallel with a common electrolyte supply, even though each individual cell is galvanically isolated. If the parallel cells are operated at different voltages, an electrochemical potential gradient is formed across the electrolyte tube manifold, causing stray currents to flow from one cell to the other. It is important to determine and reduce stray currents and its implications to ensure high system efficiency and maximum system lifetime. This work presents a new approach with which stray currents between parallel operated, galvanically isolated electrochemical cells has been determined for the first time. For this purpose, an ionic 4-point measurement was implemented into an experimental setup with two electrolyzer flow cells with a common electrolyte supply using reference electrodes. This approach was used to measure the potential differences ΔE between both electrolyzers exemplarily for alkaline water electrolysis. Combined with the measured ionic resistances of the electrolyte within the polymeric tube manifold, stray currents were accurately determined. The presented results show that the ionic 4-point measurement could be successfully implemented and validated to experimentally determine stray currents between parallelly operated cells. The method presented enabled stray current measurements with high precision in the mA range. Due to the high cell currents and high ionic tube resistance, the stray current is less than 1 % in the introduced electrochemical setup. The demonstrated systematic measurement approach can be easily transferred to other electrochemical systems or processes.

Sensor for operational control of oxygen and combustible gases concentration in waste gases of thermal units

A new sensor has been developed for continuous monitoring of oxygen and combustible gases content in the waste gases of thermal units. The target application of the sensor is its installation in shunt pipes of thermal units, directly into the waste gas flow. The sensor is characterized by one reference gas electrode and three measuring electrodes applied on the surface of a solid electrolyte tube made of a zirconia electrolyte (e.g., 8YSZ). The reference gas electrode and one of the measuring electrodes were made of silver, the second measuring electrode was made of platinum, the third measuring electrode was made of a mixture of zinc oxide (95 wt %) and lanthanum-strontium manganite (5 wt %). The oxygen content in the gas mixture was determined by the well-known potentiometric method in accordance with the Nernst equation, i.e. an Ag|8YSZ|Ag electrochemical cell was used. To determine the products of incomplete combustion of fuel, the method of mixed potential between Pt- and Zn-based electrodes was used; the obtained potential value was determined by the difference in the oxidation rate of carbon monoxide as the main component of unburned fuels, on different materials of measuring electrodes. The experimental results of the sensor for the determination of carbon monoxide, hydrogen, and methane in a gas mixture are presented.

Yttria-Stabilized Zirconia Assisted Green Electrochemical Preparation of Silicon from Solid Silica in Calcium Chloride Melt

A novel integrated cell with O2-|YSZ|Pt|O2(air) reference and counter electrodes was constructed using a short yttria-stabilized zirconia solid electrolyte (YSZ) tube. Combining with cyclic voltammetry and potentiostatic electrolysis methods, green electrochemical preparation of Si from solid SiO2 in CaCl2 melt at 1173 K was studied via an experimental apparatus containing the novel integrated cell under completely carbon-free conditions; the effect of electrolysis time on the morphology of the Si product was also investigated by scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM-EDS). The results show that the morphology of the product obtained from potentiostatic electrolysis at a low overpotential (− 1.6 V) undergoes an evolution from SiO2 raw powder with different sizes to aggregates of spherical particles and small particles with partial reduction, and then to Si nuclei, and finally to Si wires or flakes. The morphology of electrolytic products has little relation with that of SiO2 raw powder and may be controlled by applying different potentials. Furthermore, the longer the electrolysis time, the more the Si wires grow, and the higher the Si purity overall. It is feasible that the experimental apparatus without the sealed stainless steel reactor and any carbonaceous materials can be used to prepare Si from solid SiO2 in CaCl2 melt and release O2 gas at the same time.

The Renaissance of Liquid Metal Batteries

Next-generation batteries with long life, high-energy capacity, and high round-trip energy efficiency are essential for future smart grid operation. Recently, Cui et al. demonstrated a battery design meeting all these requirements—a solid electrolyte-based liquid lithium-brass/zinc chloride (SELL-brass/ZnCl2) battery. Such a battery design overcomes some inherent problems of conventional ZEBRA batteries and lithium ion batteries.

Molten Lithium-Brass/Zinc Chloride System as High-Performance and Low-Cost Battery

Summary Batteries with high safety, low cost, and reasonable energy density are essential for grid-scale energy storage and still remain elusive. Here, we report a solid electrolyte-based liquid lithium-brass/zinc chloride (SELL-brass/ZnCl2) battery using garnet-type lithium-ion solid electrolyte, lithium anode, and brass/ZnCl2 cathode. The chemistry of the cell reaction and the ability of being assembled in discharged state ensures a high safety. The use of low-cost ZnCl2 cathode can realize a low cell material cost of $16 kWh−1. The adoption of lithium anode guarantees a high theoretical energy density of 750 Wh kg−1 and 2,250 Wh L−1. Moreover, by using brass powder as a Zn source in the cathode, the Zn particle growth issue is successfully solved, and a good cycling stability of the battery can be obtained. As full cell performance and scalability are also verified, our SELL-brass/ZnCl2 battery shows a high potential for practical use in grid energy storage.

LaScO3-based electrolyte for protonic ceramic fuel cells: Influence of sintering additives on the transport properties and electrochemical performance

In this work, the effect of the content of CuO, ZnO, Al2O3, NiO, Fe2O3, Co3O4 and MoO3 additives on the sinterability, microstructure, and electrical properties of La0.9Sr0.1ScO3-α proton-conducting oxide in a form of tubes produced by slip casting is studied. It is shown that the relative density of La0.9Sr0.1ScO3-α tubes without sintering aids is ~86%. The introduction of 1.0 wt % ZnO, Al2O3, NiO or 0.5 ÷ 1.0 wt % Co3O4 leads to a relative density of ceramics higher than 95%. Among dense ceramic tubes, LSS +0.5 wt % Co3O4 has the highest electrical conductivity. The introduction of 1 wt % Fe2O3 additive does not affect the sinterability of the LSS, and 1 wt % CuO and MoO3 inhibits LSS sintering. Single protonic ceramic fuel cells based on LSS +0.5 wt % Co3O4 and LSS +1.0 wt % NiO supporting electrolyte tubes with a thickness of 300 μm are studied. The maximum power density of about 30 mW/cm2 at 800 °C was obtained for a cell based on LSS +0.5 wt % Co3O4 using wet hydrogen as fuel and air as an oxidizing gas.

An intermediate temperature garnet-type solid electrolyte-based molten lithium battery for grid energy storage

Batteries are an attractive grid energy storage technology, but a reliable battery system with the functionalities required for a grid such as high power capability, high safety and low cost remains elusive. Here, we report a solid electrolyte-based molten lithium battery constructed with a molten lithium anode, a molten Sn–Pb or Bi–Pb alloy cathode and a garnet-type Li6.4La3Zr1.4Ta0.6O12 (LLZTO) solid electrolyte tube. We show that the assembled Li||LLZTO||Sn–Pb and Li||LLZTO||Bi–Pb cells can stably cycle at an intermediate temperature of 240 °C for about one month at current densities of 50 mA cm−2 and 100 mA cm−2 respectively, with almost no capacity decay and an average Coulombic efficiency of 99.98%. Furthermore, the cells demonstrate high power capability with current densities up to 300 mA cm−2 (90 mW cm−2) for Li||LLZTO||Sn–Pb and 500 mA cm−2 (175 mW cm−2) for Li||LLZTO||Bi–Pb. Our design offers prospects for grid energy storage with intermediate temperature operations, high safety margin and low capital and maintenance costs.

Thermal behavior of heat-pipe-assisted alkali-metal thermoelectric converters

The alkali-metal thermal-to-electric converter (AMTEC) changes thermal energy directly into electrical energy using alkali metals, such as sodium and potassium, as the working fluid. The AMTEC system primarily consists of beta-alumina solid electrolyte (BASE) tubes, low and high-pressure chambers, an evaporator, and a condenser and work through continuous sodium circulation, similar to conventional heat pipes. When the sodium ions pass through the BASE tubes with ion conductivity, this ion transfer generates electricity. The efficiency of the AMTEC directly depends on the temperature difference between the top and bottom of the system. The optimum design of components of the AMTEC, including the condenser, evaporator, BASE tubes, and artery wick, can improve power output and efficiency. Here, a radiation shield was installed in the low-pressure chamber of the AMTEC and was investigated experimentally and numerically to determine an optimum design for preventing radiation heat loss through the condenser and the wall of AMTEC container. A computational fluid dynamics (CFD) simulation was carried out to decide the optimum size of the low-pressure chamber. The most suitable height and diameter of the chamber were 270 mm and 180 mm, respectively, with eight BASE tubes, which were 150 mm high, 25 mm in diameter, and 105 mm in concentric diameter. Increasing the temperature ratio (T Cond /T B ) led to high power output. The minimum dimensionless value (0.4611) for temperature (T Cond /T B ) appeared when the radiation shield was made of 500-mesh nickel. Simulation results for the best position and shape for the radiation shield, revealed that maximum power was generated when a stainless steel shield was installed in between the BASE tubes and condenser.

Magnesia-stabilised zirconia solid electrolyte assisted electrochemical investigation of iron ions in a SiO2-CaO-MgO-Al2O3 molten slag at 1723 K.

Production of metallic iron through molten oxide electrolysis using inert electrodes is an alternative route for fast ironmaking without CO2 emissions. The fact that many inorganic oxides melt at ultrahigh temperatures (>1500 K) challenges conventional electro-analytical techniques used in aqueous, organic and molten salt electrolytes. However, in order to design a feasible and effective electrolytic process, it is necessary to best understand the electrochemical properties of iron ions in molten oxide electrolytes. In this work, a magnesia-stabilised zirconia (MSZ) tube with a closed end was used to construct an integrated three-electrode cell with a "MSZ|Pt|O2 (air)" assembly functioning as the solid electrolyte, the reference electrode and also the counter electrode. Electrochemical reduction of iron ions was systematically investigated on an iridium (Ir) wire working electrode in a SiO2-CaO-MgO-Al2O3 molten slag at 1723 K by cyclic voltammetry (CV), square wave voltammetry (SWV), chronopotentiometry (CP) and potentiostatic electrolysis (PE). The results show that the electroreduction of the Fe2+ ion to Fe on the Ir electrode in the molten slag follows a single two-electron transfer step, and the rate of the process is diffusion controlled. The peak current on the obtained CVs is proportional to the concentration of the Fe2+ ion in the molten slag and the square root of scan rate. The diffusion coefficient of Fe2+ ions in the molten slag containing 5 wt% FeO at 1723 K was derived to be (3.43 ± 0.06) × 10-6 cm2 s-1 from CP analysis. However, a couple of subsequent processes, i.e. alloy formation on the Ir electrode surface and interdiffusion, were found to affect the kinetics of iron deposition. An ECC mechanism is proposed to account for the CV observations. The findings from this work confirm that zirconia-based solid electrolytes can play an important role in electrochemical fundamental research in high temperature molten slag electrolytes.

Preparation of an electrochemical sensor for measuring the silicon content in molten iron

A silicon sensor for measuring the silicon content in molten iron that included a new membrane electrode was synthesized by coating a slurry of CaF2, SiO2 and 5% Polyvinyl alcohol (PVA) onto the surface of a ZrO2 (MgO) solid electrolyte tube, followed by sintering in a high purity Ar atmosphere. The influences of the preparation conditions, such as the chemical composition, solid (CaF2+SiO2 powder) to liquid (5% PVA solution) ratio and sintering temperature, on the coating layer adhesive properties, active ingredients and detection performance of the formed auxiliary electrode layer were systematically investigated. It is indicated that the synthesized coating layer showed strong adhesive properties and the main active ingredients were SiO2 (ZrSiO4) solid particles-CaO·MgO·2SiO2 solid solution under the optimum preparation conditions. The as-prepared silicon sensor, which was used to detect the silicon content in molten iron at 1450°C, exhibited superior performance. When the silicon content ranged from 0.5 to 1.5% in liquid iron, the testing result from the silicon sensor with a response time of 15s and steady time greater than 30s agreed well with the values from the chemical analysis method.

Formation free energy of sodium stannate measured using β-β″-Al2O3 ceramic electrolyte

β-β″-Al2O3 precursor powder was successfully prepared by a solid-phase sintering method with Li2CO3, Na2CO3 (as the sources of Li2O and Na2O, respectively) and α-Al2O3 powder as the raw materials. The precursor was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results indicate that the amount of Na2O in the raw materials has a great effect on the formation of β″-Al2O3 in the β-β″-Al2O3 precursor. When Na2O content is 10 wt%, the content of β″-Al2O3 phase reaches the maximum value of 86.24 wt% in the precursor. The β-β″-Al2O3 ceramic was prepared from β-β″-Al2O3 precursor powder by isostatic pressing and burying sintering process. The conductive property of the β-β″-Al2O3 ceramic was examined by electrochemical impedance spectroscopy (EIS) method, and the density was measured by the Archimedes method. The results reveal that when 10 wt% Na2O was added, the sample exhibits the best performance with the lowest resistivity of 4.51 Ω·cm and the highest density of 3.25 g·cm−3. A solid electrolyte battery of Pt|SnO2, Na2SnO3|β-β″-Al2O3|NaCrO2, Cr2O3|Pt was assembled by the β-β″-Al2O3 electrolyte tube to measure the open potential of the resulting battery, and the formation free energy of sodium stannate was calculated. In the temperature range of 1273–773 K, the relationship between formation free energy of sodium stannate and temperature was generated as follows: \(\Delta G_{{{\text{Na}}_{ 2} {\text{SnO}}_{ 3} }}^{0 } = - 1040.83 + 0.2221T \pm 7.54\).

Calcination temperature dependence of synthesis process and hydrogen sensing properties of In-doped CaZrO3

The CaZr0.9In0.1O3-δ can be used as solid electrolyte material for high temperature hydrogen sensors. In this paper, thermogravimetric–differential thermal analysis and X-ray diffractometer analysis were employed to investigate the calcination temperature dependence of fabricating this material. The results show that CaZrO3 matrix phase can be synthesized directly by CaO and ZrO2 at 1000 °C or stepwise by intermediate oxide CaZr4O9 at higher temperatures between 1000 °C and 1200 °C during solid-state reaction process. Doping of indium into CaZrO3 occurs in the temperature range of 1200 °C–1400 °C. With calcination temperature exceeding 1400 °C, no obvious improvement of doping occurs. Even a sharp deterioration of doping effect happens with a temperature of 1550 °C. The CaZr0.9In0.1O3-δ electrolyte powders with a main phase purity of 98.75% were synthesized at 1400 °C for 10 h. The electrolyte tubes with a relative density of 96.8% and a homogeneous crystal size between 2 μm and 3 μm are fabricated out. Hydrogen sensor assembled with the electrolyte tube exhibits good hydrogen sensing performance obeying the Nernst law at 700 °C–800 °C.

Determination of Hydrogen Content and Dehydrogenation in Molten Aluminum by Concentration Cell Method

The CaZr0.9In0.1O3-α proton conductor was prepared by solid reaction method with high purity and small particle size. Two types hydrogen sensors and pump based on the proton conductor were fabricated for monitoring the hydrogen content and dehydrogenation in molten aluminum at 760 . The °C electromotive force (EMF) and time of hydrogen sensor with the inverted-U electrolyte tube followed a smooth curve in which the EMF tended to be stable after about 13 min whose sensing performance was superior to that with the upright-U electrolyte tube. The sensor EMF increased with the pressure or flow rate of referent gas according to Nernst equation. The equilibrium time of EMF increased and the transferring resistance between the Pt electrode and proton conductor’s transfer resistance decreased with the flow rate of reference gas. Therefore, inverted-U type tube and flow rate value of reference gas were very important to acquire the sensitive and accurate hydrogen content values in molten aluminum. In addition, hydrogen pump based on concentration cell had feasibility and actual using value for the dehydrogenation of molten aluminum.

Effect of Basicity on Electroreduction with Controlled Oxygen Flow of Molten Slag Containing FeO

This paper reports on electroreduction with controlled oxygen flow (COF) for extraction of iron along with oxygen by-product from molten slags containing iron oxide at 1723 K. An electrolytic cell with COF was constructed by an iridium wire cathode and a porous platinum anode sintered on a one-end-closed magnesia-stabilized zirconia-based solid electrolyte tube. Effect of basicity of SiO2–CaO–Al2O3–MgO–FeO slag on electroreduction behavior of FeO was investigated by means of the linear sweep and the potentiostatic electrolysis. The possibility of the zirconia membrane as conductive noncorrosive anode material was also discussed. The results indicate that both cathode alloying and increasing slag basicity are helpful to the FeO electrolytic reduction in the molten slag. With the iridium wire as a cathode and an applied voltage at 2.5 V, higher slag basicity results in higher electrolysis rate and higher reduction ratio of the FeO; however, silicon is also precipitated during electrolysis. The applied voltage can cause the increased porosity in the zirconia membrane. The corrosion of the molten slag to the zirconia membrane during electrolysis is evidently aggravated when the slag basicity reaches 0.8. In order to minimize the corrosion of the molten slag to the zirconia membrane during electrolysis, the slag basicity of 0.6 is relatively advisable for extraction of iron under conditions of experimentation.

ELECTROCHEMICAL BEHAVIOR OF Ni2+ IN SiO2-CaO-MgO-Al2O3 MOLTEN SLAG AT 1673 K

The modern iron and steel industry produces large emissions of CO2 annually. Electrolytic reduction of molten slag containing iron oxide at high temperature using an inert oxygen evolving anode is an alternative process to reduce or eliminate the formation of CO2. In order to establish reasonable process parameters of electrolytic method for steel containing Ni, it is necessary to master the electrochemical behavior of Ni + in molten slag. However, investigations on the electrochemical behavior of Ni in molten slag at higher temperatures were very limited, which can probably be attributed to the experimental difficulties associated with the operation of high-temperature electrochemical cells. An electrolytic cell with a controlled oxygen flow and Pt, O2(air)|ZrO2 used as reference electrode was constructed integrally through a one-end-closed magnesia partially stabilized ZrO2 solid electrolyte tube. Electrochemical behavior of Ni + on Ir electrode was investigated in SiO2-CaO-MgO-Al2O3 molten slag at 1673 K by means of electrochemical techniques such as cyclic voltammetry (CV), square wave voltammetry (SWV), chronopotentiometry (CP) and potentiostatic electrolysis. The results show that both diffusion in the molten slag and electromigration in the ZrO2 solid electrolyte for the O are not rate-determining steps of electrochemi*国家自然科学基金项目51174148和武汉科技大学大学生科技创新基金研究项目14ZRA004资助 收到初稿日期: 2015-01-22,收到修改稿日期: 2015-04-27 作者简介:洪川,男, 1990年生,硕士生 DOI: 10.11900/0412.1961.2015.00065 第1001-1009页 pp.1001-1009

Study on the Characteristics of an Alkali-Metal Thermoelectric Power Generation System

In the present study, a numerical simulation and experimental studies of an alkali-metal thermoelectric energy converter (AMTEC) system were carried out. The present, unique AMTEC model consists of an evaporator, a β-alumina solid electrolyte (BASE) tube, a condenser, and an artery cable wick. The key points for operation of the present AMTEC were 1100 K in the evaporator and 600 K in the condenser. A numerical model based on sodium-saturated porous wicks was developed and shown to be able to simulate the AMTEC system. The simulation results show that the AMTEC system can generate up to 100 W with a given design. The AMTEC system developed in the present work and used in the practical investigations could generate an electromotive force of 7 V. Artery wick and evaporator wick structures were simulated for the optimum design. Both sodium-saturated wicks were affected by numerous variables, such as the input heat power, cooling temperature, sodium mass flow rate, and capillary-driven fluid flow. Based on an effective thermal conductivity model, the presented simulation could successfully predict the system performance. Based on the numerical simulation, the AMTEC system operates with efficiency near 10% to 15%. In the case of an improved BASE design, the system could reach efficiency of over 30%. The system was designed for 0.6 V power, 25 A current, and 100 W power input. In addition, in this study, the temperature effects in each part of the AMTEC system were analyzed using a heat transfer model in porous media to apply to the computational fluid dynamics at a predetermined temperature condition for the design of a 100-W AMTEC prototype. It was found that a current density of 0.5 A/cm2 to 0.9 A/cm2 for the BASE is suitable when the temperatures of the evaporator section and condenser section are 1100 K and 600 K, respectively.

Fluoride Based Solid Electrolyte Tubes for Electrochemical Sensing

Under reducing conditions fluoride based solid electrolyte sensors with sulphur-sensitive auxiliary electrodes are able to measure the sulphur content in liquid metals and gases at elevated temperatures. In this work CaF2 doped with YF3 and SrF2 doped with LaF3 were selected as solid electrolyte material, because of their high ionic conductivity. Solid electrolyte tubes were prepared from these materials by slip casting to apply them as electrochemical sensors e.g. in the float glass industry.

Electrochemical Behavior of Ni Ion in SiO2-CaO-MgO-Al2O3 Molten Slag

A novel electrolytic cell with Pt,O2(air)|ZrO2 used as reference electrode was constructed integrally by using a one-end-closed magnesia partially stabilized zirconia solid electrolyte tube. Various electrochemical measurement techniques such as cyclic voltammetry (CV), chronopotentiometry (CP) and chronoamperometry (CA) were applied, and thermodynamic software Factsage was combined to study the effects of NiO concentration and temperature on electrochemical behavior of Ni ion in SiO2-CaO-MgO-Al2O3 molten slag at temperatures not less than 1673 K. The results indicate that Ni in molten slag is in stable form of Ni2+ instead of Ni3+; reduction of Ni2+ in molten slag is a diffusion control reaction process with a single step; smaller concentration of NiO and higher temperature lead to better reversibility of Ni2+ reduction reaction; with CV, CP and CA electrochemical measurement techniques, diffusion coefficients of Ni2+ at 1723 K are derived, respectively. Further, diffusion activation energy of Ni2+ from data corresponding to CV and CA techniques is derived from Arrhenius equation factored in diffusion coefficient and temperature.

Comparison Between Anode‐Supported and Electrolyte‐Supported Ni‐CGO‐LSCF Micro‐tubular Solid Oxide Fuel Cells

AbstractTwo types of micro‐tubular hollow fiber SOFCs (MT‐HF‐SOFCs) were prepared using phase inversion and sintering; electrolyte‐supported, based on highly asymmetric Ce0.9Gd0.1O1.95(CGO) HFs and anode‐supported based on co‐extruded NiO‐CGO(CGO)/CGO HFs. Electroless plating was used to deposit Ni onto the inner surfaces of the electrolyte‐supported MT‐HF‐SOFCs to form Ni‐CGO anodes. LSCF‐CGO cathodes were deposited on the outer surface of both these MT‐HF‐SOFCs before their electrochemical performances were compared at similar operating conditions. The performance of the anode‐supported MT‐HF‐SOFCs which delivered ca. 480 mW cm–2 at 600 °C was superior to the electrolyte‐supported MT‐HF‐SOFCs which delivered ca. six times lower power. The contribution of ohmic and electrode polarization losses of both FCs was investigated using electrochemical impedance spectroscopy. The electrolyte‐supported MT‐HF‐SOFCs had significantly higher ohmic and electrode polarization ASR values; this has been attributed to the thicker electrolyte and the difficulties associated with forming quality anodes inside the small (<1 mm) lumen of the electrolyte tubes. Further development on co‐extruded anode‐supported MT‐HF‐SOFCs led to the fabrication of a thinner electrolyte layer and improved electrode microstructures which delivered a world leading 2,400 mW cm–2. The newly made cell was investigated at different H2 flow rates and the effect of fuel utilization on current densities was analyzed.

An electrochemical device with a multifunctional sensor for gas diffusivity measurement in fuel cells

Mass transport is of paramount importance to the electrochemical performance of fuel cells. The high performance of fuel cells requires a large diffusion coefficient, i.e. the diffusivity, of the gas transport in electrodes and efficient gas diffusion can lead to large limiting currents and controlled concentration polarization. Recently-designed electrochemical devices allow for the direct evaluation of gas diffusivity in fuel cells. To realize these devices, a gas pump and an oxygen sensor are typically attached to two different spots of the inside wall of an electrolyte tube, which inevitably induces the uncertainty in measurement temperature. To eliminate temperature uncertainty in the diffusivity measurement, an electrochemical device with a multifunctional sensor is designed in this report. Quantitative analysis shows that temperature uncertainty can indeed induce substantial evaluation errors of gas diffusivity, limiting current density and concentration polarization, which in turn verifies the necessity of the multifunctional sensor device for the accurate diffusivity measurement in fuel cells.