Investigation into the effect of Fe-site substitution on the performance of Sr2Fe1.5Mo0.5O6-δ anodes for SOFCs

Ni-substituted Sr₂Fe_1.5-xNi_xMo_0.5O_6-δ (SFNM) materials have been investigated as anode catalysts for intermediate temperature solid oxide fuel cells. Reduced samples (x = 0.05 and 0.1) maintained the initial perovskite structure after reduction in H₂, while metallic nickel particles were detected on the grain surface for x = 0.2 and 0.3 using transmission electron microscopy. Temperature programmed reduction results indicate that the stable temperature for SFNM samples under reduction conditions decreases with Ni content. In addition, X-ray photoelectron spectroscopy analysis suggests that the incorporation of Ni affects the conductivity of SFNM through changing the ratios of Fe³⁺/Fe²⁺ and Mo⁶⁺/Mo⁵⁺. Sr₂Fe_1.4Ni_0.1Mo_0.5O_6-δ shows the highest electrical conductivity of 20.6 S cm^-1 at 800 °C in H₂. The performance of this anode was further tested with electrolyte-supported cells, giving 380 mW cm^-2 at 750 °C in H₂, hence demonstrating that Ni doping in the B-site is beneficial for Sr₂Fe_1.5Mo_0.5O_6-δ anode performance. 

Battery modelling methods for electric vehicles - a review

Electric vehicles (EVs) and hybrid electric vehicles (HEVs) are rapidly gaining popularity as a means of de-carbonization in the transport sector in tackling sustainable energy supply and environment pollution problems. To build a proper battery model is essential in predicting battery behaviour under various operating conditions for avoiding unsafe battery operations and developing proper controlling algorithms and maintenance strategies. This paper presents a comprehensive review of battery modelling methods. In particular, the mechanism and characteristics of Li-ion batteries are presented, and different modelling methods are discussed. Considering that equivalent electric circuit models (EECMs) are the most widely used, a detailed analysis of the modelling procedure is presented.

A new battery modelling method based on simulation error minimization

A new battery modelling method is presented based on the simulation error minimization criterion rather than the conventional prediction error criterion. A new integrated optimization method to optimize the model parameters is proposed. This new method is validated on a set of Li ion battery test data, and the results confirm the advantages of the proposed method in terms of the model generalization performance and long-term prediction accuracy.

Real-time estimation of battery internal temperature based on a simplified thermoelectric model

Li-ion batteries have been widely used in the EVs, and the battery thermal management is a key but challenging part of the battery management system. For EV batteries, only the battery surface temperature can be measured in real-time. However, it is the battery internal temperature that directly affects the battery performance, and large temperature difference may exist between surface and internal temperatures, especially in high power demand applications. In this paper, an online battery internal temperature estimation method is proposed based on a novel simplified thermoelectric model. The battery thermal behaviour is first described by a simplified thermal model, and battery electrical behaviour by an electric model. Then, these two models are interrelated to capture the interactions between battery thermal and electrical behaviours, thus offer a comprehensive description of the battery behaviour that is useful for battery management. Finally, based on the developed model, the battery internal temperature is estimated using an extended Kalman filter. The experimental results confirm the efficacy of the proposed method, and it can be used for online internal temperature estimation which is a key indicator for better real-time battery thermal management.

Effect of cation structure on the oxygen solubility and diffusivity in a range of bis{(trifluoromethyl)sulfonyl}imide anion based ionic liquids for lithium-air battery electrolytes

This paper reports on the solubility and diffusivity of dissolved oxygen in a series of ionic liquids (ILs) based on the bis{(trifluoromethyl)sulfonyl}imide anion with a range of related alkyl and ether functionalised cyclic alkylammonium cations. Cyclic voltammetry has been used to observe the reduction of oxygen in ILs at a microdisk electrode and chronoamperometric measurements have then been applied to simultaneously determine both the concentration and the diffusion coefficient of oxygen in the different ILs. The viscosity of the ILs and the calculated molar volume and free volume is also reported. It is found that, within this class of ILs, the oxygen diffusivity generally increases with decreasing viscosity of the neat IL. An inverse relationship between oxygen solubility and IL free volume is reported for the two IL families implying oxygen is not simply occupying the available empty space. In addition, it is reported that the introduction of ether-group into the IL cation structure promotes the diffusivity of dissolved oxygen but reduces the solubility of the gas.

Anodes for protonic ceramic fuel cells (PCFCs)

One of the more promising possibilities for future “green” electrical energy generation is the protonic ceramic fuel cell (PCFC). PCFCs offer a low-pollution technology to generate electricity electrochemically with high efficiency. Reducing the operating temperature of solid oxide fuel cells (SOFCs) to the 500-700°C range is desirable to reduce fabrication costs and improve overall longevity. This aim can be achieved by using protonic ceramic fuel cells (PCFCs) due to their higher electrolyte conductivity at these temperatures than traditional ceramic oxide-ion conducting membranes. This thesis deals with the state of the art Ni-BaZr0.85Y0.15O3-δ cermet anodes for PCFCs. The study of PCFCs is in its initial stage and currently only a few methods have been developed to prepare suitable anodes via solid state mechanical mixing of the relevant oxides or by combustion routes using nitrate precursors. This thesis aims to highlight the disadvantages of these traditional methods of anode preparation and to, instead, offer a novel, efficient and low cost nitrate free combustion route to prepare Ni-BaZr0.85Y0.15O3-δ cermet anodes for PCFCs. A wide range of techniques mainly X-ray diffraction (XRD), scanning electron microscopy (SEM), environmental scanning electron microscopy, (ESEM) and electrochemical impedance spectroscopy (EIS) were employed in the cermet anode study. The work also offers a fundamental examination of the effect of porosity, redox cycling behaviour, involvement of proton conducting oxide phase in PCFC cermet anodes and finally progresses to study the electrochemical performance of a state of the art anode supported PCFC. The polarisation behaviour of anodes has been assessed as a function of temperature (T), water vapour (pH2O), hydrogen partial pressures (pH2) and phase purity for electrodes of comparable microstructure. The impedance spectra generally show two arcs at high frequency R2 and low frequency R3 at 600 °C, which correspond to the electrode polarisation resistance. Work shows that the R2 and R3 terms correspond to proton transport and dissociative H2 adsorption on electrode surface, respectively. The polarization resistance of the cermet anode (Rp) was shown to be significantly affected by porosity, with the PCFC cermet anode with the lowest porosity exhibiting the lowest Rp under standard operating conditions. This result highlights that porogens are not required for peak performance in PCFC anodes, a result contrary to that of their oxide-ion conducting anode counterparts. In-situ redox cycling studies demonstrate that polarisation behaviour was drastically impaired by redox cycling. In-situ measurements using an environmental scanning electron microscopy (ESEM) reveal that degradation proceeds due to volume expansion of the Ni-phase during the re-oxidation stage of redox cycling.The anode supported thin BCZY44 based protonic ceramic fuel cell, formed using a peak performing Ni-BaZr0.85Y0.15O3-δ cermet anode with no porogen, shows promising results in fuel cell testing conditions at intermediate temperatures with good durability and an overall performance that exceeds current literature data.

School of the Battery Commander, November 1917

A book from the School of Battery Commander which is an instruction manual for field artillery. The chapters are titled: Chapter 1 - Definitions, Chapter 2 - The Trajectory, Chapter 3 - Dispersion, Chapter 4 - Use of the "Plan Directeur" or the Map for the Preparation of Fire,

Certificate for One Hundred Preference Shares in the Tait Storage Battery Company, Limited

Certificate for 100 preference shares in The Tait Storage Battery Company, Limited to the estate of Hamilton K. Woodruff, March 2, 1934.

Certificate for Twenty Shares of Capital Stock in The Tait Storage Battery Company, Limited

Certificate for 20 shares of capital stock in The Tait Storage Battery Company Limited to the estate of Hamilton K Woodruff, March 2, 1934.

Lithium Containing Complex Metal Oxides and Metal phosphates:Investigations on their synthesis and various characterizations for rechargeable lithium battery applications

The work presented in the thesis is centered around two important types of cathode materials, the spinel structured LixMn204 (x =0.8to1.2) and the phospho -oIivine structured LiMP04 (M=Fe and Ni). The spinel system LixMn204, especially LiMn204 corresponding to x= 1 has been extensively investigated to understand its structural electrical and electrochemical properties and to analyse its suitability as a cathode material in rechargeable lithium batteries. However there is no reported work on the thermal and optical properties of this important cathode material. Thermal diffusivity is an important parameter as far as the operation of a rechargeable battery is concerned. In LixMn204, the electronic structure and phenomenon of Jahn-Teller distortion have already been established theoretically and experimentally. Part of the present work is an attempt to use the non-destructive technique (NDT) of photoacoustic spectroscopy to investigate the nature of the various electronic transitions and to unravel the mechanisms leading to the phenomenon of J.T distortion in LixMn204.The phospho-olivines LiMP04 (M=Fe, Ni, Mn, Co etc) are the newly identified, prospective cathode materials offering extremely high stability, quite high theoretical specific capacity, very good cycIability and long life. Inspite of all these advantages, most of the phospho - olivines especially LiFeP04 and LiNiP04 show poor electronic conductivity compared to LixMn204, leading to low rate capacity and energy density. In the present work attempts have been made to improve the electronic conductivity of LiFeP04 and LiNiP04 by adding different weight percentage MWNT .It is expected that the addition of MWNT will enhance the electronic conductivity of LiFeP04 and LiNiP04 with out causing any significant structural distortions, which is important in the working of the lithium ion battery.

Structural, electrical and electrochemical characterization of high frequency magnetron sputtered spinel oxide cathode films for lithium ion battery applications

The main challenges in the deposition of cathode materials in thin film form are the reproduction of stoichiometry close to the bulk material and attaining higher rates of deposition and excellent crystallinity at comparatively lower annealing temperatures. There are several methods available to develop stoichiometric thin film cathode materials including pulsed laser deposition; plasma enhanced chemical vapor deposition, electron beam evaporation, electrostatic spray deposition and RF magnetron sputtering. Among them the most versatile method is the sputtering technique, owing to its suitability for micro-fabricating the thin film batteries directly on chips in any shape or size, and on flexible substrates, with good capacity and cycle life. The main drawback of the conventional sputtering technique using RF frequency of 13.56MHz is its lower rate of deposition, compared to other deposition techniques A typical cathode layer for a thin film battery requires a thickness around one micron. To deposit such thick layers using convention RF sputtering, longer time of deposition is required, since the deposition rate is very low, which is typically 10-20 Å/min. This makes the conventional RF sputtering technique a less viable option for mass production in an economical way. There exists a host of theoretical and experimental evidences and results that higher excitation frequency can be efficiently used to deposit good quality films at higher deposition rates with glow discharge plasma. The effect of frequencies higher than the conventional one (13.56MHz) on the RF magnetron sputtering process has not been subjected to detailed investigations. Attempts have been made in the present work, to sputter deposit spinel oxide cathode films, using high frequency RF excitation source. Most importantly, the major challenge faced by the thin film battery based on the LiMn2O4 cathode material is the poor capacity retention during charge discharge cycling. The major causes for the capacity fading reported in LiMn2O4cathode materials are due to, Jahn-Teller distortion, Mn2+ dissolution into the electrolyte and oxygen loss in cathode material during cycling. The work discussed in this thesis is an attempt on overcoming the above said challenges and developing a high capacity thin film cathode material.

Tubular Organization of SnO₂ Nanocrystallites for Improved Lithium Ion Battery Anode Performance

Porous tin oxide nanotubes were obtained by vacuum infiltration of tin oxide nanoparticles into porous aluminum oxide membranes, followed by calcination. The porous tin oxide nanotube arrays so prepared were characterized by FE-SEM, TEM, HRTEM, and XRD. The nanotubes are open-ended, highly ordered with uniform cross-sections, diameters and wall thickness. The tin oxide nanotubes were evaluated as a substitute anode material for the lithium ion batteries. The tin oxide nanotube anode could be charged and discharged repeatedly, retaining a specific capacity of 525 mAh/g after 80 cycles. This capacity is significantly higher than the theoretical capacity of commercial graphite anode (372 mAh/g) and the cyclability is outstanding for a tin based electrode. The cyclability and capacities of the tin oxide nanotubes were also higher than their building blocks of solid tin oxide nanoparticles. A few factors accounting for the good cycling performance and high capacity of tin oxide nanotubes are suggested.

El juego y la resolución de conflictos a través del Macarthur Story Stem Battery : estudio comparativo entre niños normales y con dificultades en el desarrollo de 4 a 6 años.

Conocer cómo resuelven los conflictos niños normales y niños con dificultades en el desarrollo de entre 4 a 6 años y qué características presentan los niños que tienen dificultades en el desarrollo. La muestra consta de 99 niños de entre 4 y 6 años,68 pertenecientes a escuelas de Cerdanyola y Ripollet y 31 niños que recibían asistencia psicológica en los centros de atención precoz (Dapsi) de Cerdanyola del Vallès y de Sant Cugat. Primero se presenta una recopilación de los principales autores clásicos sobre el tema del juego, partiendo desde el psicoanálisis, la teoría cognitiva, la escuela rusa y la terapia de juego no directiva, y posteriormente se presentan los instrumentos en los que el juego se ha utilizado como diagnóstico. Finalmente se exponen algunas de las bases para el análisis del lenguaje narrativo del niño. En la segunda parte, que corresponde a la investigación empírica, los niños fueron filmados durante la aplicación del MSSB y después se codificó cada respuesta entre dos tipos: las respuestas prosociales y las no sociales. También se registraron las consecuencias que mencionaban los niños cuando no respondían de una forma social. Finalmente se registró el tipo de juego y el nivel de ansiedad durante la aplicación del instrumento. MacArthur Story Stem Battery. Este instrumento utiliza los muñecos de la familia para la comprensión de las historias planteadas a los niños, quienes a través del lenguaje y de su narración completan y resuelven la historia planteada. Por lo tanto se analiza tanto el lenguaje del niño como su capacidad de juego. Los resultados muestran que los niños normales respondían de una forma prosocial más veces que los niños con retraso en el desarrollo. Cuando los niños respondían de una forma no social, la consecuencia más común era el castigo en igual porcentaje en ambos grupos. El personaje más frecuente fue la madre y su representación fue de tipo positivo en los dos grupos. El tipo de juego predominante fue el juego simple (juego en el que el niño representa acciones) seguido por el juego simbólico, y el juego de tipo exploratorio sólo se presentó en el grupo de niños con retraso en el desarrollo y se observó que estaba asociado a los niños que padecían déficit de atención. Finalmente el nivel de ansiedad fue mínimo en los niños normales, mientras que en el grupo de niños con retraso en el desarrollo se observaron varios casos de tensión e inhibición. La conclusión general es que los niños entre 4 y 6 años muestran distintas formas de afrontar y resolver los conflictos planteados dependiendo del grupo de estudio y de la presencia de uno o varios trastornos psicológicos. Los niños del grupo control muestran un mejor desarrollo de la moral y mejores relaciones familiares que los niños del grupo clínico.

The use of the bi-factor model to test the uni-dimensionality of a battery of reasoning tests

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Partial scalar invariance and observed differences across gender in a reasoning test battery

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