[en] Highlights: • A composite anode with endogenous Fe-Ni alloy nanoparticles has been prepared. • The redox reversibility of the anode has been confirmed by XRD. • The E_a of H_2 oxidation at the anode is much smaller than that at Ni-YSZ anode. • A ScSZ supported cell achieves MPD of 0.71 Wcm"−"2 and R_p of 0.16 Ω cm"2 at 800 °C. • The single cell shows stable output during 105 h testing at 800 °C 0.7 V in wet H_2". - Abstract: A redox reversible composite anode with Fe-Ni alloy nanoparticles in situ growth on SrLaFeO_4-type and LaFeO_3-type oxide substrates has been prepared for intermediate temperature solid oxide fuel cell (IT-SOFC) by reducing perovskite precursor La_0_._4Sr_0_._6Fe_0_._7_5Ni_0_._1Nb_0_._1_5O_3_-_δ (LSFNNb) in wet H_2 at 900 °C for 1 h. The anode has shown an excellent electrochemical catalytic activity for oxidation of hydrogen with much smaller E_a (25.1 ∼ 68.9 kJ mol"−"1) than the value (>160 kJ mol"−"1) at Ni-YSZ anode. A scandium stabilized zirconia (ScSZ) electrolyte supported SOFC with the anode achieves maximum power densities of 0.71, 0.52, 0.35, and 0.21 W cm"−"2 at 800, 750, 700 and 650 °C, respectively in wet H_2 (3% H_2O), and the corresponding R_p of 0.16, 0.21, 0.35, and 0.60 Ω cm"2 under OCV. Moreover, the single cell shows stable power output during ∼105 h operation at 800 °C under 0.7 V in wet H_2 after a initial degradation, indicating that R-LSFNNb is an excellent candidate as anode of IT-SOFC.

[en] Although the lithium-ion batteries (LIBs) have been increasingly applied in consumer electronics, electric vehicles, and smart grid, they still face great challenges from the continuously improving requirements of energy density, power density, service life, and safety. To solve these issues, various studies have been conducted surrounding the battery design and management methods in recent decades. In the hope of providing some inspirations to the research in this field, the state of the art of design and management methods for LIBs are reviewed here from the perspective of process systems engineering. First, different types of battery models are summarized extensively, including electrical model and multi-physics coupled model, and the parameter identification methods are introduced correspondingly. Next, the model based battery design methods are reviewed briefly on three different scales, namely, electrode scale, cell scale, and pack scale. Then, the battery model based battery management methods, especially the state estimation methods with different model types are thoroughly compared. The key science and technology challenges for the development of battery systems engineering are clarified finally. (topical review)

[en] Battery materials research is of crucial importance to the development of next-generation batteries. However, the transition from lab-scale studies, typically in gram quantities, to industrially relevant ones (i.e., kilogram scale) has been holding back by challenges in scale-up synthesis and a lack of reliable approaches to verify the electrochemical performance of the lab-made materials. Here the design and assembly procedures of sub-Ah-scale pouch cells that provide validations of several lab-made Li-ion and Na-ion cathode materials available in a limited quantity (<5 g) are reported. These lab-made pouch cells show superior cycle stability and consistency over the widely used coin cells, exemplified by multiple Ni-rich layered oxide-graphite full batteries retaining 84.29 ± 0.16% of the initial capacities over 1000 cycles. A four-electrode pouch cell with a reparable reference electrode is further designed to monitor impedance growth and Li plating during long-term electrochemical tests. It can be further integrated with in situ ultrasonic imaging to enable multi-modal studies. This work provides a powerful platform to evaluate and boost the technology readiness levels of laboratory-discovered battery materials. (© 2024 Wiley‐VCH GmbH)

[en] In this study, impact of pyrolyzing atmosphere on the catalytic activity and structure of non-precious metal Co-based catalysts for oxygen reduction reaction in acid and alkaline medium are investigated. These non-precious metal Co-based catalysts are prepared from pyrolyzing carbon-supported cobalt diethylenetriamine chelate (CoDETA/C) in Ar, N₂ and CO₂ atmosphere, respectively. X-ray diffraction indicates that metallic Co nanoparticles with different size are present on each catalyst. X-ray photoelectron spectroscopy shows that the Nat.% is CoDETA/C-Ar (1.54) > CoDETA/C-N₂ (1.39) > CoDETA/C-CO₂ (0.42), pyridinic-N and amino-N in CoDETA/C-N₂ is the highest among these three catalysts, while pyrrolic-N, graphitic-N and oxidized-N in CoDETA/C-Ar is higher than that in the other two catalysts. Electrochemical activity demonstrated by cyclic voltammograms and rotating ring disk electrode in O₂-saturated acid and alkaline electrolyte shows that pyrolyzing atmosphere has an important effect on the catalytic activity and a maximum catalytic activity is obtained in N₂ atmosphere, followed by in Ar then CO₂ atmosphere, in terms of onset and half-wave potentials, ORR peak potential and current, limiting current, number of electrons transferred and H₂O selectivity. The increase in catalytic activity may mainly attribute to the enhanced contents of pyridinic-N and amino-N

[en] The lithium-ion battery was first commercially introduced by Sony Corporation in 1991 using LiCoO₂ as the cathode material and mesocarbon microbeads (MCMBs) as the anode material. After continuous research and development for 25 years, lithium-ion batteries have been the dominant energy storage device for modern portable electronics, as well as for emerging applications for electric vehicles and smart grids. It is clear that the success of lithium-ion technologies is rooted to the existence of a solid electrolyte interphase (SEI) that kinetically suppresses parasitic reactions between the lithiated graphitic anodes and the carbonate-based non-aqueous electrolytes. Recently, major attention has been paid to the importance of a similar passivation/protection layer on the surface of cathode materials, aiming for a rational design of high-energy-density lithium-ion batteries with extended cycle/calendar life. In this article, the physical model of the SEI, as well as recent research efforts to understand the nature and role of the SEI are summarized, and future perspectives on this important research field will also be presented. (topical review)

[en] In this work we report a novel scalable strategy to prepare a lithium-air battery electrode from 3D N-doped pierced graphene microparticles (N-PGM) with highly active performance. This approach has combined the merits of spray drying technology and the hard template method. The pierced structured graphene microparticles were characterized physically and electrochemically. An x-ray photoelectron spectrometer and Raman spectra have revealed that the novel structure possesses a higher N-doping level than conventional graphene without the pierced structure. A much higher BET surface area was also achieved for the N-PGM than the conventional N-doped graphene microparticles (N-GM). Cyclic voltammetry indicated that the lithium-air battery with the N-PGM electrode has a better utilization for the graphene mass and a higher void volume for Li_2O_2 formation than that of the N-GM electrode. N-PGM also exhibits improved decomposition kinetics for Li oxide species yielded in the cathodic reaction. Charge and discharge measurements showed that the N-PGM lithium-air battery achieved an improved specific capacity and an enhanced cycle performance than when an N-GM electrode is used. (paper)

[en] Highlights: • An RBF network based hybrid model is proposed to predict PV cell temperature. • A parameter identification method with regularization strategy is developed. • The model prediction performance is evaluated by laboratory and commercial plants. Accurate and reliable prediction of photovoltaic (PV) cell operating temperature is vital for performing accurate output power prediction. Although numerous mathematical models have been developed to capture the effect of environmental variables on PV cell temperature, the prediction accuracy needs to be further improved and a relatively general modeling framework needs to be developed to enhance adaptability for different PV cell types. In this study, a novel radial basis function (RBF) neural network assisted hybrid modeling strategy is proposed to predict the PV cell temperature. The hybrid model is designed as an explicit mathematical formulation combined with an RBF neural network assisted correcting factor. The known function formulation is induced from prior knowledge and the unknown correcting factor is modeled by the RBF neural network. The hybrid cell temperature model is combined with the equivalent circuit model and the effectiveness of cell temperature and output power prediction is evaluated. The results illustrate that the proposed method can perform accurately cell temperature and output power prediction for both laboratory and commercial plants. It is thus indicated that the proposed hybrid modeling strategy could provide a potential general solution framework of cell temperature and output power prediction for different PV cells.

[en] In this study, a series of Fe-based non-noble metal and non-macrocycle catalysts, FeTETA/C, for oxygen reduction reaction (ORR) have been synthesized by pyrolyzing carbon-supported iron triethylenetetramine chelate at various temperatures in an inert atmosphere. Electrochemical characterization revealed that heat treatment temperature plays an essential role on improving the catalytic property of the obtained catalysts for ORR, and the optimal could be achieved at 800 °C with an ORR peak potential of 0.751 V and an electron-transfer number of 3.85. Furthermore, the obtained optimal catalyst has excellent methanol-tolerance and acceptable acid-resistance. The effects of heat treatment temperature on microstructure of the catalysts as well as the elemental state on the optimal catalyst surface have been investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS).

[en] Highlights: • A robust artificial SEI layer with abundant covalent bonds on Si anode is rationally designed. • An ultrathin SEI layer of 10 nm is obtained owing to the tremendously decreased interfacial side reaction upon cycling. • High initial Coulombic efficiency of 91.4% and robust cycling stability over 1000 cycles are achieved. Nanostructured silicon-based materials are the promising anodes for next-generation lithium-ion batteries. However, as the result of the weak adhesion of solid-electrolyte interphase (SEI) to Si, the fracture, exfoliation and subsequent regrowth of SEI layer on the expanded Si remains unsolved, leading to low initial Coulombic efficiency (ICE) (50–80%). Herein, the Ti‒Si covalent bond between nano-Si and MXene-derived artificial SEI layer is elaborately introduced, to effectively strengthen the interfacial stability and suppress the excessive interfacial side reaction. Upon the three-times expansion during first cycling, the as-obtained anodes with the ultrathin SEI still deliver a high ICE of 91.4%. Due to the stable interfacial ionic conduction, remarkable capacity retention of 90.7% after 1000 cycles at 5 A g⁻¹ with an average Coulombic efficiency of 99.8% could be maintained. This strategy provides new insight into designing durable alloy anodes from the point of the interfacial adhesion strength.

[en] Sodium metal batteries (SMBs) using gel polymer electrolytes (GPEs) with high theoretical capacity and low production cost are regarded as a promising candidate for high energy-density batteries. However, the inherent flammability of GPEs and uncontrolled Na dendrite caused by inferior mechanical properties and interfacial stability hinder their practical applications. Herein, an anion-trapping fireproof composite gel electrolyte (AT-FCGE) is designed through a chemical grafting-coupling strategy, where functionalized boron nitride nanosheets (M-BNNs) used as both nanosized crosslinker and anion capturer are coupled with poly(ethylene glycol)diacrylate in poly(vinylidene fluoride-co-hexafluoropropylene) matrix, to expedite Na${}^{+}$ transport and suppress dendrite growth. Experimental and calculation studies suggest that the anion-trapping effect of M-BNNs with abundant Lewis-acid sites can promote the dissociation of salts, thus remarkably improving the ionic conductivity and Na${}^{+}$ transference number. Meanwhile, the formation of highly crosslinked semi-interpenetrating network can effectively in situ encapsulate non-flammable phosphate without sacrificing the mechanical properties. Consequently, the resulting AT-FCGE shows significantly enhanced Na${}^{+}$ conductivity, mechanical properties, and excellent interfacial stability. The AT-FCGE enables a long-cycle stability dendrite-free Na/Na symmetric cell, and prominent electrochemical performance is demonstrated in solid-state SMBs. The approach provides a broader promise for the great potential of fire-retardant gel electrolytes in high-performance SMBs and the beyond. (© 2023 Wiley‐VCH GmbH)