Solid-state Storage Research Articles

Experimental and theoretical validation of the solid-state heat storage device using the latent heat of martensitic transformation in shape memory alloy

Experimental and theoretical validation of the solid-state heat storage device using the latent heat of martensitic transformation in shape memory alloy

Constructal design of weight optimized metal hydride storage device embedded with ribbed honeycomb

Solid state storage of hydrogen offers few advantages over compressed and liquefied forms. As heat transfer being the major factor controlling charging and discharging, several thermal enhancement methods were reported in literature. However parasitic weight of thermal enhancement structures embedded to the storage bed can reduce its gravimetric storage capacity. As total weight of the device for given hydrogenation capacity and charging rate being an important factor, these structures needs to be weight optimized. The present study propose a ribbed honeycomb embedded to the multi-tubular storage device with sodium alanate as the storage alloy. The shape and size of this conform to the constructal law, analogous to bio transport systems. This ensures efficient transfer of sorption heat from the point of maximum temperature in the hydride bed to the coolant. The device designed for charging 0.01 kg of hydrogen in 10 min weighs 1.2 kg at optimum length/thickness ratio. This numerical study is conducted using COMSOL Multiphysics™ commercial code.

Titanium Dioxide for Hydrogen Economy: a Brief Review

Our research is mainly focused on solving problems related to the production of hydrogen and its storage, as well as the creation of autonomous energy systems using renewable energy sources. Technological solutions for green energy depend on the development of new materials with desired properties that are able to reversibly accumulate hydrogen under appropriate environmental conditions (temperature, pressure) and on the technological processes allowing to obtain molecular hydrogen without significant energy consumption. The creation of materials with fundamentally new characteristics is inextricably linked with the production of nanoscale systems with properties that are controlled at the atomic and molecular level. The review considers the results of studies on the possibilities of using various nanostructures of titanium dioxide known for its catalytic properties and high stability in various applications of hydrogen energy. Much attention is paid to the promising direction of solid-state storage of hydrogen using hydride pastes and high-entropy alloys.

Features of Designing a Low-Speed Generator for the Accumulation of Gravitational Energy

The article is devoted to the study of increasing the efficiency of low-speed synchronous generators with permanent magnets as part of a system with a gravitational energy storage. Features analysis of the gravitational energy storage devices use was carried out. The shortcomings of pumped-storage power plants in comparison with solid-state storage power plants are considered. Practical significance: the research results were used in the development of low-speed generators with permanent magnets for use in a system with a gravitational energy storage. They can significantly reduce the weight and size of the system as a whole.

A fully solid-state cold thermal energy storage device for car seats using shape-memory alloys

A fully solid-state cold thermal energy storage device for car seats using shape-memory alloys

Paving the Way to the Fuel of the Future-Nanostructured Complex Hydrides.

Hydrides have emerged as strong candidates for energy storage applications and their study has attracted wide interest in both the academic and industry sectors. With clear advantages due to the solid-state storage of hydrogen, hydrides and in particular complex hydrides have the ability to tackle environmental pollution by offering the alternative of a clean energy source: hydrogen. However, several drawbacks have detracted this material from going mainstream, and some of these shortcomings have been addressed by nanostructuring/nanoconfinement strategies. With the enhancement of thermodynamic and/or kinetic behavior, nanosized complex hydrides (borohydrides and alanates) have recently conquered new estate in the hydrogen storage field. The current review aims to present the most recent results, many of which illustrate the feasibility of using complex hydrides for the generation of molecular hydrogen in conditions suitable for vehicular and stationary applications. Nanostructuring strategies, either in the pristine or nanoconfined state, coupled with a proper catalyst and the choice of host material can potentially yield a robust nanocomposite to reliably produce H2 in a reversible manner. The key element to tackle for current and future research efforts remains the reproducible means to store H2, which will build up towards a viable hydrogen economy goal. The most recent trends and future prospects will be presented herein.

First-Principles Study of Adsorption of Methane on Defective Silicene

Considering the significance of natural gas, such as methane, and the difficulties in storing it, research is increasingly focusing on developing materials for solid-state methane storage. Two-dimensional materials have a large number of possible adsorption sites for gas molecules due to their high surface-to-volume ratio. However, the two-dimensional structure is chemically inactive and attracts nonpolar gases rather weakly. We investigated the methane gas adsorption capabilities of silicene by activating it with different defects. According to our density functional theory calculations, the mono-vacancy (MV) defect is advantageous in increasing the binding strength of energy-carrying gases such as methane. In MV defective silicene, methane adsorption energy is detected in the order of the internationally specified energy regime.

A New Joint Strategy for Multi-Criteria Decision-Making: A Case Study for Prioritizing Solid-State Drive

Solid-state data storage is becoming a widely accepted technology and is looking for new ways to provide cost-effective solutions across various information systems. Solid-state drives (SSDs), existing in different types and models, have several sustainable features: storage, dimensions, volume, etc. Due to the wide range of attributes, designing a robust method can easily select from the purchaser/retailer/wholesaler point of view. This work offers a joint multi-criteria decision-making (MCDM) to rank SSD alternatives, and a newly developed approach, namely Measurement Alternatives and Ranking according to the Compromise Solution (MARCOS) technique, is utilised, and a comparative investigation has also been achieved with other MCDM methods. Data of separate SSDs have been collected from the Indian market with twenty-six different models of eleven brands. The Bonferroni operator (BFO) allocates and compiles the objective weights using the Entropy weights technique (EWT), the Criteria Importance through Inter criteria Correlation (CRITIC) and the Method based on the Removal Effects of Criteria (MEREC). The sensitivity analysis using objective weights considering 18 scenarios was performed, and analysis with the Standard deviation shows that the joint MCDM possesses high accuracy and robustness. The results achieved have been tested with Spearman’s rank and Wojciech-Salabun (WS) coefficient, and the first rank goes to SSD-7. The presented results benefit the manufacturers to understand the market requirement better and for the consumer to make a wise decision while purchasing SSD. It also offers future scope for applying the proposed methodology in similar areas, social sciences and engineering, to make complex decisions.

Limits of a rechargeable spin battery

We discuss how the ideal rechargeable energy accumulator can be made and what the limits for solid-state energy storage are. We show that in theory, spin batteries based on heavy fermions can surpass chemical ones in terms of energy capacitance. The absence of chemical reactions in spin batteries makes them more stable, and also they do not need to be heated in cold conditions. We study how carrier statistics and the density of states affect the energy capacity of the battery. Also, we discuss hypothetical spin batteries based on neutron stars.

Synthesis Method of Unsolvated Organic Derivatives of Metal Borohydrides

A new, scalable, wet-chemistry single-pot method of synthesising pure unsolvated organic derivatives of metal borohydrides is presented. The metathetic reaction in a weakly coordinating solvent is exemplified by the synthesis of [(n-C4H9)4N][Y(BH4)4] and [Ph4P][Y(BH4)4] systems. For the latter compound, the crystal structure was solved and described. Organic borohydride salts obtained by the new method can find various applications, e.g., can be used as precursors in synthesis of hydrogen-rich mixed-metal borohydrides-promising materials for solid-state chemical storage of hydrogen.

Latent heat thermal storage of solid-state phase transition in thermally stabilized hexagonal FeS

Large amounts of heat are required in areas such as food processing and textile industries to maintain equipment in the medium-temperature zone 393–573 K. However, thermal storage materials that work at this temperature are rare. Hexagonal iron sulfide FeS exhibits a solid-state phase transition at 420 K, accompanied by a high entropy change. The quenched FeS is unstable when subjected to a thermal cycling test, and the related entropy change declines. A secondary hexagonal phase with Fe deficiency was confirmed by neutron powder diffractions. Annealing FeS at temperatures slightly higher than Tt can accelerate the formation of the secondary phase. Once the sample is stabilized, the entropy change is no longer changeable. The thermally stabilized FeS sample exhibits a relatively high thermal storage density up to 136 J/cm3. This work suggests a new solid candidate for the application of solid-state phase transition latent heat energy storage in the medium-temperature region.

MAID-Q: Minimizing Tail Latency in Embedded Flash With SMR Disk via -Learning Model

As the mainstream solid-state storage technology, NAND flash has the advantages of tiny size, cost-effective, and high performance, which make it a promising candidate to be embedded into the shingled magnetic recording (SMR) disk to build a faster, denser, and cheaper storage system. However, such an embedded flash with SMR (EF-SMR) disk system suffers from lengthy tail-latency due to “reclamation issues” in both the NAND flash and the SMR disk. Our preliminary observations reveal that tremendous idle time intervals exist in real-world scenarios, and few prior works have focused on addressing the tail-latency issue in the EF-SMR disk. In this article, we propose a novel method termed MAID-Q to fully exploit the idle time intervals to minimize the lengthy tail-latency of the EF-SMR disk based on a lightweight reinforcement learning model (i.e., the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Q$ </tex-math></inline-formula> -learning model). In addition, fine-grained block-level space management and a parallel reclamation strategy are proposed to improve the reclamation efficiency and hide the reclamation overheads. The effectiveness of our proposed design was evaluated with realistic I/O traces, and the results show that the proposed design can remedy the tail-latency by 88.31% and improve the overall performance by 79.03%.

Mechanisms of Lithium-Ion Transport in Solid-State Electrolyte and Cathode Materials Prepared By PVD

Conventional liquid-state lithium-ion batteries are currently limited in their energy density, lifetime, thermal stability, and safety. The design of viable solid-state batteries shows promise to improve upon the shortcomings of liquid cells. Removal of organic electrolytes increases the lifetime while making these batteries more environmentally friendly and safe. Solid-state batteries also have the potential to demonstrate higher energy density and provide ultrafast charging. However, these desirable properties require significant efforts to uncover and utilize the chemical, morphological, and electrochemical properties of solid-state electrolytes and cathode nanocomposites. This study addresses physical vapor deposition (PVD) technology for design of solid-state material architectures with the properties needed to create high-performance electrochemical cells. The PVD process allows cathodes and electrolytes to be deposited as dense films, thereby increasing their energy density and electrochemical performance. Furthermore, this process results in excellent adhesion between dissimilar materials allowing for increased electrical and ionic conductivity. This work uses lithium oxyhalide electrolytes and eco-friendly lithium iron phosphate cathodes, which were both deposited in vacuum using radio frequency power and magnetron sputtering sources. A co-deposition technique was used to successfully deposit thin film layers of cathode, electrolyte, cathode/electrolyte mixture, and carbon thin films in a single process. Electrochemical cells with different functional layers deposited by PVD (~7 mm) were compared to the cells with commercial LFP cathodes (~32 mm thick). The electrochemical cells created by PVD showed lower charge transfer resistances and high electrochemical stability at ultra-high (10C) charging rates. Significant improvements in performance are expected to continue as the process is improved in terms of ionic and electronic transport at cathode-electrolyte interfaces. The authors acknowledge financial support from the DOD Navy SBIR Phase II project (N68335-18-C-0021), the NSF IUCRC program for supporting the “Center for solid-state electric power storage” (#2052631), and the South Dakota “Governor’s Research Center for electrochemical energy storage”. Figure 1

The direct modification of metal Cu interface for high-performing solid-state anode via KCu7S4/Cu7S4 interconversion mechanism

It is worthwhile and promising to explore the direct activation of metal Cu for aqueous solid-state batteries. Herein, a simple strategy of in situ electrochemical interface modification is proposed to produce KCu7S4 film on a Cu foam substrate. The as-fabricated KCu7S4 products possess a desirable physical hierarchical structure, satisfactory wire array homogeneity as well as high mass loading (∼45 mg cm−2). The KCu7S4 electrode as an anode for solid-state energy storage has an areal capacity of 11.98 mAh cm−2 (at 10 mA cm−2), which is far superior to the previous best result (<5 mAh cm−2). As revealed by the durability test, the electrode retains a high coulombic efficiency of 86.8 % after cycling. The well-assembled KCu7S4//NiO single solid-state battery displays an improved energy density of 87.5–66 Wh m−2 under the power range of 73–730 W m−2. Besides, the working mechanism based on KCu7S4/Cu7S4 interconversion, and the reaction kinetics of electrode are deeply analyzed via a series of in situ techniques. This work contributes a promising solution to the fabrication of Cu-based film anodes which may lead to significant progress in large-scale energy storage technology.

Excellent energy storage and mechanical performance in hetero-structure BaTiO3-based relaxors

BaTiO3-based lead-free ceramics are mainstays of electrical functional materials in industry with mature technology and relatively low cost. However, the huge challenge of low recoverable energy storage density (Wrec) has long restricted their development in solid-state energy storage capacitors. Here, an ultrahigh Wrec of ∼9.04 J cm−3 and a large efficiency (η) of ∼87.2% are realized in BaTiO3-based relaxor ceramics via designing heterostructure formed by coexisting rhombohedral-tetragonal multiphase ergodic polar nanoregions. Encouragingly, outstanding mechanical properties (Vickers hardness ∼9.7 Gpa, compressive strength ∼500 MPa) are also achieved and the structural correlation between the energy storage and mechanical properties has been established, which are linked to the synergistic mechanisms of solid solution strengthening, denseness strengthening, grain boundary strengthening, and twin boundary strengthening. It is particular significance that this work provides an effective strategy to design new high-performance dielectric materials, accelerating the development of BaTiO3-based lead-free capacitors used in advanced energy-storage devices.

Optimal Selection of Materials for Hydrogen Solid-State Storage

Optimal Selection of Materials for Hydrogen Solid-State Storage

Mechanical and Structural Evaluation of LiSrH3 Perovskite Hydride for Solid State Hydrogen Storage Purposes

Increasing catastrophic climate events, energy needs, human population lead to look for clean, cheap and environmentally friendly energy production methods and sources. International agreements have been made to lower carbon emissions and support carbon free way of energy productions. Hydrogen technology is suggested one excellent way of accomplishing these aims. Hydrogen is an excellent energy carrier with almost zero carbon emission and high efficiency. There are four steps to make hydrogen energy ready for usage: production, transportation, storage and converting it to electricity. Each steps have its own obstacles to be overcome. Among the storage methods, solid state storage of hydrogen is very promising since it allows us to store hydrogen in high content safely. Thus, there are intense ongoing research on this area. Therefore, this study adopts a well proved, time and cost saving method density functional theory to search and evaluate mechanical and electronic properties of LiSrH3 perovskite hydride with space group Pm3 ̅m (221) for hydrogen storage purposes. Two critical parameters gravimetric hydrogen density and hydrogen desorption temperature along with elastic constants, Poisson’s ratio, Shear, bulk, Young modulus are collected and discussed. The mechanical evaluation is demonstrated that LiSrH3 is a mechanically stable material, however, elastic constant evaluation is showed that it is a brittle material which can be an obstacle when handling the material. The electronic band structure is also obtained which demonstrated an indirect band gap of 3.65 eV.

A flexible supercapacitor with high capacitance retention at an ultra-low temperature of -65.0°C

A novel anti-freezing organo-hydrogel electrolyte is developed to improve capacitance retention of flexible supercapacitor at the ultra-low temperature. The electrolyte is composed of graphene/polyvinyl alcohol matrix and methyl sulfoxide/water/sulfuric acid mixture. It simultaneously possesses a high tensile strength of ca.2.58 MPa and a high ionic conductivity of ca.3.9 S/m. Furthermore, the electrolyte can still maintain high flexibility and high ionic conductivity (ca.1.0S/m) at -65℃. In addition, a flexible supercapacitor with sandwich structure was assembled from the organo-hydrogel electrolyte and two polyaniline fiber/carbon cloth electrodes. The supercapacitor exhibits a high specific capacitance of 252.0F/g and excellent capacitance retention of 93% at -65℃. The excellent capacitance retention is attributed to the synergistic effect of methyl sulfoxide, concentrated sulfuric acid and graphene nanosheets. This study provides a new way to design and prepare anti-freezing electrolyte with high-performance for application in the flexible solid-state electrochemical energy storage at ultra-low temperatures.

Numerical investigation of thermal and electrical management during hydrogen reversible solid-state storage using a novel heat exchanger based on thermoelectric modules

In order to reduce the costs generated by the hydrogen solid storage tank's accessories such as the heat exchanger, this work was carried out. It shows thermal and electrical investigations of transient hydrogen (H2) solid storage in a tank filled with porous medium (LaNi5) to activate a potential PEM automotive fuel cell. For this purpose, we use a novel heat exchanger with a heat sink combined with thermoelectric modules (TEMs). We realize a simulation that helps us verify if thermoelectric exchanger will be an alternative to the conventional ones. The main results are that a thermoelectric cooler and heater with 127 couples of semiconductors coupled with 19 fins heat sink could be used during the reversible hydrogen solid storage. Also, results show that we can avoid the water freezing at negative temperatures when using a conventional heat exchanger by using TEM during hydrogen absorption. Finally, during the endothermic desorption of the hydrogen, TEG use can avoid boiling water used in the heating system. Also, the hydrogen tank will be lighter and compact without fins and water tubes.

Structure–Property Relationships for Polyether-Based Electrolytes in the High-Dielectric-Constant Regime

Establishing general structure–property relationships for polymer electrolytes is crucial to enable design of improved materials to advance solid-state energy storage. We report the relationship between dielectric constant, glass transition temperature, and ionic conductivity for polyether-based electrolytes with dielectric constants of the polyether host within the range 7–35 at 60 °C. The ionic conductivities of the polyether and lithium bis(trifluoromethylsulfonyl)imide mixtures ranged from 10–7 to 10–3 S/cm. In this higher-dielectric-constant regime, here defined as a polymer with a dielectric constant greater than that of poly(ethylene oxide) (ca. 9.0), the glass transition temperature increased with dielectric constant while ionic conductivity decreased. These results complement a recent report on the low-dielectric-constant regime, where the ionic conductivity was limited by the dielectric constant and ion dissociation. In the high-dielectric-constant regime explored here, segmental dynamics are slowed due to stronger polymer–polymer and polymer–ion interactions, resulting in decreased ionic conductivity and associated increase in neat polymer glass transition temperature. The disparate chemical structures of the polymers of this study, along with the results of past coarse-grained molecular dynamics simulations, support the generality of these conclusions and speak to the difficulty of identifying a single molecular characteristic leading to the design of high-conductivity polymer electrolytes. Widely used poly(ethylene oxide) represents a near-optimal balance between the low- and high-dielectric-constant regimes. To improve upon the ionic conductivity limitations of polymer electrolytes, single-component polymer hosts are unlikely to resolve the trade-off between the need for ion dissociation while retaining rapid segmental dynamics.