Thermochemical Energy Storage Material Research Articles

Optimising thermochemical energy storage: a comprehensive analysis of CaCO3 composites with CaSiO3, CaTiO3, and CaZrO3.

With the increasing amount of renewable energy produced, many governments and industries are pushing for the installation of battery energy storage system (BESS) solutions. Thermal batteries are systems that store heat made from various energy sources, and can be used to produce electricity upon demand. These systems are easily scalable and can be installed in cities, homes and remote locations. Thermochemical energy storage (TCES) uses the enthalpy of a chemical reaction to store and release heat through endothermic and exothermic processes, respectively. CaCO3 has been identified as an ideal TCES material as it is cheap and abundant, but maximising long-term cyclability is key to ensure battery longevity. This article investigates the addition of CaSiO3, CaTiO3 and CaZrO3 to CaCO3 in a 1 : 1 ratio to ascertain the reaction properties and cyclic capacity over time. Cycling longevity and thermodynamic properties were determined using simultaneous differential scanning calorimetry and thermogravimetric analysis (DSC-TGA) along with the Sieverts technique, and their reaction pathway studied by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The low cost of the CaCO3-CaSiO3 material of $1.8 USD per kW hth suggests that if a suitable particle refinement agent were to be employed to ensure cycling longevity this material would be an excellent TCES material. Despite the CO2 cycling capacity of the CaCO3-CaZrO3 system only reducing by 16 wt% over 100 cycles, the cost of ZrO2 brings the materials cost to $30.9 USD per kW hth, making this material currently unsuitable for application. The CaCO3-CaTiO3 system showed only a 17% drop in total CO2 uptake over 100 cycles, although the cost was $11.1 USD per kW hth.

A Review of Thermochemical Energy Storage Systems for District Heating in the UK

Thermochemical energy storage (TCES) presents a promising method for energy storage due to its high storage density and capacity for long-term storage. A combination of TCES and district heating networks exhibits an appealing alternative to natural gas boilers, particularly through the utilisation of industrial waste heat to achieve the UK government’s target of Net Zero by 2050. The most pivotal aspects of TCES design are the selected materials, reactor configuration, and heat transfer efficiency. Among the array of potential reactors, the fluidised bed emerges as a novel solution due to its ability to bypass traditional design limitations; the fluidised nature of these reactors provides high heat transfer coefficients, improved mixing and uniformity, and greater fluid-particle contact. This research endeavours to assess the enhancement of thermochemical fluidised bed systems through material characterisation and development techniques, alongside the optimisation of heat transfer. The analysis underscores the appeal of calcium and magnesium hydroxides for TCES, particularly when providing a buffer between medium-grade waste heat supply and district heat demand. Enhancement techniques such as doping and nanomaterial/composite coating are also explored, which are found to improve agglomeration, flowability, and operating conditions of the hydroxide systems. Furthermore, the optimisation of heat transfer prompted an evaluation of heat exchanger configurations and heat transfer fluids. Helical coil heat exchangers are predominantly favoured over alternative configurations, while various heat transfer fluids are considered advantageous depending on TCES material selection. In particular, water and synthetic liquids are compared according to their thermal efficiencies and performances at elevated operating temperatures.

Li4SiO4-Based Heat Carrier Derived from Different Silica Sources for Thermochemical Energy Storage

Thermochemical energy storage (TCES) is one of the key technologies facilitating the integration of renewable energy sources and mitigating the climate crisis. Recently, Li4SiO4 has been reported to be a promising heat carrier material for TCES applications, owing to its moderate operation temperature and stability. During the synthetic processes, the properties of the Si source used directly influence the performance of derived Li4SiO4 materials; however, the internal relations and effects are not yet clear. Hence, in this work, six kinds of SiO2 sources with different phases, morphology, particle size, and surface area were selected to synthesize a Li4SiO4-based TCES heat carrier. The physicochemical properties of the SiO2 and the corresponding derived Li4SiO4 were characterized, and the comprehensive performance (e.g., heat storage/releasing capacity, rate, and cyclic stability) of the Li4SiO4 samples was systematically tested. It was found that the silica microspheres (SPs), which possess an amorphous phase, uniform micro-scale structure, and small particle size, could generate Li4SiO4 TCES materials with a highest initial capacity of 777.7 kJ/kg at 720 °C/900 °C under pure CO2. As a result, the SP-L showed an excellent cumulative heat storage amount of 5.84 MJ/kg within 10 heat-releasing/storage cycles, which was nearly 1.5 times greater than the value of Li4SiO4 derived from commonly used silicon dioxide. Furthermore, the effects of the utilized Si source on the performance of as-prepared Li4SiO4 and corresponding mechanisms were discussed, which offers guidance for the future selection of Si sources to produce high-performance Li4SiO4-based TCES heat carriers.

Review on thermal properties and reaction kinetics of Ca(OH)2/CaO thermochemical energy storage materials

AbstractThermochemical energy storage technology is one of the most promising thermal storage technologies, which exhibits high energy storage capacity and long‐term energy storage potentials. The low‐cost, safe, and reliable calcium oxide/calcium hydroxide (CaO/Ca(OH)2) system has become the preferred thermochemical energy storage material system to solve the problem of renewable energy consumption. This study reviews the structural, thermodynamic, and kinetic properties influencing the absorption and desorption reactions of calcium oxide (CaO) and calcium hydroxide (Ca(OH)2) in thermal energy storage applications. It is found that the transformation of crystal structure from cubic to hexagonal upon hydration is attributed to volume expansion and crack formation facilitating diffusion. The specific heat capacities of CaO and Ca(OH)2, as well as reaction enthalpies, are studied across temperature ranges. Most studies on reaction kinetics are focused on the effect of factors such as temperature, particle size, and material content. Strategies to mitigate issues such as particle agglomeration and enhance reaction efficiency are discussed, including the incorporation of enhancing materials such as γ‐Al2O3. This study underscores the importance of the core reaction material content and the enhancing materials that are used to optimise energy density in thermal chemical water‐absorption and ‐desorption reactions.

Experimental study of the new composite materials for thermochemical energy storage

Thermochemical energy storage (TCES) is a promising technology to support the world's initiatives to reduce CO2 emissions and limit global warming. In this paper, we have synthesized and characterized a new three-component composite materials consisting of a mixture of calcium chloride and iron powder confined inside the expanded vermiculite. The new approaches of studying composite sorbents of ammonia using a gas flow-through microcalorimetry proposed in this work. The energetics of adsorption as a function of ammonia uptake was measured at room temperature (RT), 106 and 150 °C. The enthalpy of NH3 sorption in eight cycles tested ranged from 12.2 to 39.1 kJ mol−1. The strength of ammonia sorption on composite surface was characterized by TPD (Temperature Programmed Desorption). Based on the NH3-TPD profiles of composites it was found that the high-temperature desorption peaks of vermiculite sample shifted to lower temperature after the deposition of salt. The characterization of the composites was complemented by the laboratory analyses using XRD, WD-XRF, FTIR, TG/DTG, SEM-EDS and nitrogen sorption isotherms at −196 °C (BET method). The composite impregnated with 37 wt% of salt has the highest enthalpy and sorption capacity, thus seems to be the most promising candidates for the heat storage systems.

Oxygen Vacancy‐Rich Defects Porous Cu2MgO3/Mg0.78Cu0.22O Composite with Sinter‐Resistant and Highly Reactive for Long‐Duration High‐Temperature Thermochemical Energy Storage

AbstractHigh‐temperature thermochemical energy storage based on metal oxides is the key technology to reducing the levelized costs of electricity of the next‐generation concentrated solar power plants. CuO/Cu2O has wide availability and high energy density, but severe sintering leads to low reactivity. In this study, an innovative approach to modulate the oxygen vacancy content to change the surface properties and crystal structure to enhance the sintering resistance and redox reversibility is proposed. The re‐oxidation degree is increased from 46% to 99%, and the energy release rate is increased by 3.5 times. It remains 99.9% reduction and 97.1% oxidation activity after 3000 cycles, which is very valuable for engineering applications. Cu2MgO3 and Mg0.78Cu0.22O are prone to form oxygen vacancies, which promotes the formation of porous structures. Mg0.78Cu0.22O helps Cu2MgO3/CuO/Cu2O deliver more O through the surface. Mg0.78Cu0.22O is firmly and uniformly dispersed on the CuO/Cu2O surface after long cycling. They have a large binding energy, more charge transfer and enhanced bond energy at the interface. The mechanism of composite in increasing the sintering temperature and long‐term reaction stability is revealed from experimental and theoretical calculations, which provides a new idea for the rational design of thermochemical energy storage materials.

Screening of organic lithium precursors for producing high-performance Li4SiO4-based thermochemical energy storage materials: Experimental and kinetic investigations

Thermochemical energy storage by using Li4SiO4 TCES materials has been considered a promising technology for efficient heat storage from high temperature sources (700–900 °C). It has been proven the utilization of organic lithium precursors could effectively improve the heat storage performance of derived Li4SiO4. Hence, in this work, 7 kinds of unreported organic lithium precursors were screened for producing high-performance Li4SiO4 TCES materials. The physicochemical properties, CO2 ad-desorption capacities and the heat storage/releasing performance of as-prepared Li4SiO4 were systematically evaluated by a series of experimental and kinetic investigations, and a dual modification effects of organic lithium precursor were revealed. As a consequence, 3 potential candidates including lithium benzoate, lithium oxalate and lithium citrate were screened out. Li4SiO4 adsorbents derived from these precursors show great heat storage amount promotions of over 50 % in comparison with the average capacity of traditional Li4SiO4 (~ 350 kJ/kg/cycle). Especially, the lithium citrate derived Li4SiO4 exhibits the greatest CO2 adsorption capacity, reaction rate and cyclic stability, leading to a cumulative storage amount of 5.9 MJ/kg within 10 cyclic heat storage/releasing processes. Above findings could provide guidance for the future development of high-performance Li4SiO4 materials and Li4SiO4-CO2 TCES systems.

Redox and melting characteristics of Mn-based ores for high-temperature thermochemical energy storage

Redox and melting characteristics of Mn-based ores were investigated to test their potential use in thermochemical energy storage (TCES). Two Mn-based materials (FJ and LY) were natural ores with the Mn content higher than 35 wt%, and one Mn-based material was prepared by adding an MgO–kaolin inert support into LY ores to increase its melting temperature. Cyclic reduction and oxidation reactivity of these Mn-based materials was studied via thermogravimetric analysis (TGA), and the melting behaviors of these materials were investigated by using a melting test setup with an optical camera–image system. It was found that the oxygen capacity of the FJ Mn ore can approach ∼1.50 wt%, while the LY Mn ore had only 0.42 wt%–0.69 wt% oxygen capacity The deformation temperature of the FJ Mn ore is higher than that of the LY Mn ore, and the melting temperatures of the LY Mn ore can be significantly improved with the addition of an MgO–kaolin inert support, while the reactivity is decreased due to the addition of the MgO–kaolin inert material. This study proves that manganese ores with high oxygen capacity and deformation temperature have potential as TCES materials. For some manganese ores with low deformation temperatures, it is necessary to improve their melting temperatures and ensure oxygen capacity for high-temperature TCES applications.

Enhancing cyclic durability in CaO-based thermochemical energy storage by Zr–Y co-doping: Mechanistic insights

The CaCO3/CaO materials are promising materials for thermochemical energy storage. However, they suffer from rapidly decreasing energy storage density over multiple calcination/carbonation cycles. This paper aims to select suitable inert supports with cyclic stability enhancement for the calcium looping (CaL) process at high carbonation reaction temperatures (＞800 °C). Firstly, four metallic elements (Zr, Mn, Y and Ce) were selected, and a single-doping strategy was used to screen out single-doping inert supports. By comparison, the 20Ca–Zr had the best energy storage performance, with an energy storage density (Eg,N=30) of 1744.72 kJ/kg after 30 cycles. Subsequently, the co-doping method was applied to further screen out co-doped combinations with long-term cyclic stability potential. The Zr was co-doped with Mn, Y and Ce, respectively. Among them, the 20Ca-0.5Zr-0.5Y displayed the best cyclic stability with an average energy storage density (Eg,av) of 1950.69 kJ/kg in 30 cycles. Based on the chosen Zr–Y co-doped CaO-based composite, the doping concentration optimization and multiple cycles tests were carried out. The effective conversion (Xeff) of 10Ca-0.5Zr-0.5Y decreased by only 4.9 % after 60 cycles. Therefore, the Zr–Y co-doped CaO-based composite, possessing robust sintering resistance effects, is promising for long-term TCES technology.

Dehydration performance of a novel solid solution library of mixed Tutton salts as thermochemical heat storage materials

To improve energy efficiency and reduce greenhouse gas emissions, energy storage technologies are of paramount importance. Thermochemical energy storage (TCES) materials offer high energy storage densities, and systems based on the dehydration of common salt hydrates like MgSO4·7H2O have been extensively investigated, though frequent problems such as agglomeration and unfavorable kinetics highlight the need for further material development. We consulted our VIENNA TCES-database and became aware of the Tutton salts, A2M(XO4)2·6H2O, (X = S or Se) which have also been previously investigated as TCES materials, although the effects of cation substitution on reactivity had remained poorly characterized. Herein, we report the synthesis and characterization of 41 mixed Tutton salts with the composition K2Zn1-xMx (SO4)2·6H2O (M = Mg, Co, Ni, Cu). Two trends were readily apparent: increasing the amount of nickel leads to a predictable increase in the dehydration onset temperature while preserving the simple form of the single dehydration step observed, while the use of copper leads to a predictable decrease in dehydration onset.

Remarkable low-temperature dehydration kinetics of rare-earth-ion-doped Ca(OH)2 for thermochemical energy storage

Thermochemical energy storage based on dehydration-hydration of Ca(OH)2/CaO reversible reaction is considered a promising strategy to address the intermittency of solar thermal energy due to its extremely high storage density, possibility of seasonal heat storage, and low cost. However, conventionally-used Ca(OH)2 particles suffer from instabilities and poor multi-cycle performance at high temperature, which limits their applications. Here, we propose rare-earth-ion-doped Ca(OH)2 materials for thermochemical energy storage at reduced dehydration temperature through extensive DFT computational screening. Rare-earth elements, Sc, Y, La, Gd and Lu, -doped Ca(OH)2 exhibit lower decomposition barrier in comparison to the Ca(OH)2 without doping. The Sc-doped Ca(OH)2 shows the significantly reduced onset temperature of ∼326 °C, which is 50 °C lower than that of the pure Ca(OH)2. Importantly, more than 3-fold increase in the dehydration rate and excellent stability during multi-cycles of the compositions at 320 °C is reached by the doping of Sc or Y into Ca(OH)2. The working performance makes this material a practical alternative to realize stable high-density solar thermal energy storage.

Thermal energy storage with flexible discharge performance based on molten-salt thermocline and thermochemical energy storage

Thermocline sensible thermal energy storage has prospects in cost-effective thermal energy storage. In this study, we combined a molten-salt thermocline with thermochemical energy storage to improve the flexibility of thermal discharge performance. For the thermochemical energy storage material, a composite was synthesized using calcium hydroxide and silicon-impregnated silicon carbide foams with an energy capacity of 1.8 MJ (0.50 kWh) and volumetric energy density of 0.79 MJ L-material−1. The composite was loaded onto an indirect fixed-bed reactor that used molten salt as the heat transfer fluid. The temperature of the composite reached 637 °C at a hydration pressure of 812 kPa. The thermochemical energy storage reactor exhibited a variable maximum outlet temperature of the heat transfer fluid in the range 524–583 °C and maximum discharge power of up to 0.6 kW (discharge power density up to 0.25 kW L-material−1) on changing the hydration pressure and flow rate of the heat transfer fluid. The results confirm the significance of thermochemical energy storage to the system in boosting the temperature of the thermocline and variable discharge performance. The novel hybrid system has a superior discharge performance compared with that of the conventional thermocline thermal energy storage, and it is a promising option for flexible large-scale energy storage and power generation driven by renewable energy.

Optimization of the Coating Process of a Ca(OH)2‐Based Thermochemical Energy Storage Material

AbstractA promising candidate for a thermochemical storage system implemented into district heating is a previously developed core‐shell material based on CaO/Ca(OH)2. Proceeding from the preliminary manufacturing process, this work aims to optimize relevant material properties as mechanical stability and shell uniformity, by varying defined parameters during a reproduceable coating procedure, ready for commercial upscaling.

Characterization of Ca-Dicarboxylate Salt Hydrates as Thermochemical Energy Storage Materials

Salt hydrates are highly promising materials for thermochemical energy storage applications to store waste heat below 200 °C. Although highly researched and theoretically promising, in practical applications salt hydrates often cannot fulfill expectations. Based on the promising results of the Ca-oxalate monohydrate/Ca-oxalate system, other Ca-dicarboxylate salt hydrates were investigated to determine whether potential materials for heat storage can be found amongst them. A simultaneous thermal analysis showed that all candidates are applicable in the temperature range of 100–200 °C, and thermally stable up to 220 °C. Calcium malonate dihydrate (637 J/g), calcium terephthalate trihydrate (695 J/g), and tetrafluoro calcium terephthalate tetrahydrate (657 J/g) have shown higher enthalpies of dehydration than Ca-oxalate monohydrate. Due to the investigation of derivatives of Ca-terephthalate, it is possible to report the crystal structure of 2-fluoro calcium terephthalate. In single crystals, it forms a trihydrate and crystallizes in the Pmna space group (Z = 4, Z’ = ½) forming infinite chains of Ca atoms. De- and rehydration reactions of the most promising candidates were studied in situ with powder X-ray diffraction showing the structural changes between the hydrate and anhydrate states.

Exploring synergistic sintering factors and nanopore regeneration of calcium-based thermochemical energy storage materials

Calcium-based thermochemical energy storage is essential for high-temperature solar energy utilization. However, performance decay is inevitable in repeated calcination/carbonation cycles, even for modified materials. In this study, the effects of synergistic sintering factors on performance decay are investigated, including chemical reaction, temperature and CO2 atmosphere. More importantly, rather than complicating the initial preparation process of the anti-sintering composites to achieve higher stability, a regeneration method is proposed to repair the nanopores of sintered composites and recover their performances. After using citric acid to dissolve materials with heavily sintered morphologies and reconstruct their porous structures, the energy storage densities of both the co-doped and benchmark materials increase by 2–4 times. The regenerated Al/Mg co-doped composite also shows high cyclic stability in subsequent long-term cycles. Furthermore, DFT calculations illustrate the strong atomic interaction between CaO and dopants. The economic analysis reveals that the regeneration costs of the co-doped composites are approximately one-half of their synthesis costs, making them a cost-efficient choice for long-term industrial application. This work expands the limited perspectives of current modification research on improving cyclic stability. It can guide the actual industrial applications of thermochemical energy storage, thus enhancing material reutilization and realizing costs reduction.

Efficient SrO-based thermochemical energy storage using a closed-loop pressure swing

The SrCO3/SrO system has recently attracted interest for thermochemical energy storage due to the high energy densities potentially attainable. However, the high temperatures needed to promote calcination involve a sintering-induced deactivation of SrO to carbonation. In this work, SrO-based samples have been tested using a closed-loop pressure swing approach involving calcinations and carbonations at absolute pressures of 0.01 bar and 1 bar CO2, respectively. Using low CO2 absolute pressure for calcination decreases the reaction temperature to 900 °C, thus reducing the deactivation of SrO. Moreover, the use of additives further improves the reactivity of the samples. The addition of ZrO2 and MgO by mechanical mixing and acetic acid treatment, respectively, results in samples with very high multicycle performance, yielding material energy storage densities after twenty cycles above 5.0 GJ/m3. These results significantly improve those obtained for similar samples in which calcinations and carbonations were carried out at an absolute pressure of 1 bar CO2. Regarding the integration of the thermochemical energy storage into concentrating solar power plants, calcining SrO-based materials at low pressure increases the net thermal-to-electric efficiencies by up to 6 % points compared to CaO-based materials calcined at the same conditions. The importance of experimental conditions and precursors in the multicycle behaviour of SrO-based materials for thermochemical energy storage is emphasized.

Fluidisation of Thermochemical Energy Storage Materials: Degradation Assessment

ABSTRACT Composite zeolites impregnated with anhydrous salt particles are promising materials for use in domestic thermochemical energy storage (TCES), however they have limited power output. Fluidization has the potential to increase the mass and heat transfer of TCES systems. In this study, a composite TCES material of LiX zeolite impregnated with MgCl2 salt is produced. This material and a LiX zeolite batch are then fluidized at different gas velocities to study whether degradation of these particles occurs when fluidizing. Images of the particles after fluidizing are analyzed using a validated method utilizing microscope images and specialized software used to study whether fragmentation or abrasion have been induced by fluidization. Composite particles were found to have increased average diameter by 7%−8%, which could be due to imperfect dehydration of these particles after the impregnation process, but also due to observed salt conglomerates present on the surface of some particles. Overall, excess degradation was not found due to fluidization at any gas velocity. No mass loss was measured in any sample after fluidization, and no appreciable fragmentation was observed. The LiX zeolite and composite particles measured 0.6192 mm and 0.6799 mm prior to fluidization and measured 0.6405 mm and 0.7088 mm after fluidization. However, this change is not statistically significant, and it is shown that a change in diameter is unlikely. Despite this, some fines have been produced which were found to have an average diameter of 3.60 μm (σ = 1, ±2.34 μm), and as such present a hazard if inhaled.

An in-depth oxidation kinetic study of CuCrxMn1-xO2 (x = 0, 0.1, 0.3) for thermochemical energy storage at medium-high temperature

In this study, we investigated the effect of Cr doping on CuMn2O4/CuMnO2 and established an oxidation (heat release) kinetic model for CuCrxMn1-xO2 (x = 0, 0.1, 0.3) as an extension of our previous research on developing medium-high temperature (500–1000 °C) redox-type thermochemical energy storage materials. Our objective is to develop a reliable model for predicting the heat release power at constant temperature conditions. The as-prepared samples were characterized using XRD Rietveld refinement, SEM-EDS, and XPS analysis to obtain a more precise crystal structure and elemental states. The oxidation kinetic model was established using an isothermal oxidation method which differs from the method (non-isothermal) used in the previous study. Additionally, the pressure term was also taken into consideration. The reaction models and kinetic parameters of CuMnO2, CuCr0.1Mn0.9O2 and CuCr0.3Mn0.7O2 were determined using master plots and Arrhenius plots. Among all sample, CuCr0.1Mn0.9O2 exhibited the smallest oxidation activation energy of 29.932 kJ/mol, which was significantly lower than the previous value obtained using the non-isothermal method. Combining the reaction rate and heat release, CuCr0.1Mn0.9O2 showed the highest instantaneous power output of 4.69 kW/kg at the oxygen partial pressure of 0.5.

Al- and Cr-doped Co3O4/CoO redox materials for thermochemical energy storage in concentrated solar power plants

The redox system of Co3O4/CoO is very promising for the thermochemical energy storage systems coupled to concentrated solar power plants because of its high energy storage density and reversibility. Nevertheless, the practical application of Co3O4/CoO system is limited by thermal hysteresis of the redox reaction and material sintering. Here, we synthesized Co-based metal oxides doped with Al and Cr, and studied the influence of the doping of these two metal elements on the thermochemical properties and sintering resistance of the pure Co3O4/CoO system. Both Al and Cr doping narrows the thermal hysteresis of the Co3O4/CoO system. In particular, when the molar doping rate of Al is 10%, the thermal hysteresis of Co–Al oxides is only 4.02 °C, which is much narrower than that of pure Co3O4, and the increase of its oxidation temperature also means that a higher level of thermal energy can be released during oxidation. In the redox cycle, the addition of Al inhibits material sintering and the formation of a loose porous structure facilitates the oxidation, ensuring the reversibility of the redox reaction. The 10% Al–Co honeycomb shows stable conversion behavior with an average conversion of 77.75% in 15 redox cycles. Co–Al oxides exhibit excellent oxidative exothermic characteristics and long-term cycle stability, making them suitable for efficient thermochemical energy-storage processes.

Directional oxygen diffusion in Cu1.5Mn1.5O4 crystals for long reversible thermochemistry

Redox activity of metal oxides are the key to the development of high-temperature thermochemical energy storage. However, few studies have reported that the reactivity of metal oxides as thermochemical energy storage is significantly affected by the changes of crystal structure and morphology during redox, caused by ion diffusion and vacancy formation and migration. In this study, we find a previously unreported high-performance thermochemical energy storage material Cu1.5Mn1.5O4 with special structure. Cu1.5Mn1.5O4 shows high energy densities during reduction and oxidation (−219.852 and 207.618 kJ/kg), and keeps 97.06% and 92.98% reactivity after 600 cycles. Voids on specific surfaces are observed after cycling, but not in the fresh sample. We find the voids provide abundant Cu2+, Mn4+ species and lattice oxygen to promote its reaction performance. Cu ions migrate obviously after oxidation and molecular dynamics simulations reveal that DCu (7.4 × 10−14 cm2 s−1) is higher than DMn (5.1 × 10−14 cm2 s−1) and DO (1.7 × 10−14 cm2 s−1). Cu1.5Mn1.5O4 exhibits voids during oxidation due to ion transport described by the Kirkendall effect. In addition, DFT calculations verify that O2− is more easily to adsorb and diffuse on (111) surface, revealing the optimal transport path and directional diffusion mechanism of O2−. These mechanisms can provide ideas for the reasonable design of materials to improve thermochemical reaction performance.