Reduction In Energy Density Research Articles

Exploring Lithium-Ion Battery Degradation: A Concise Review of Critical Factors, Impacts, Data-Driven Degradation Estimation Techniques, and Sustainable Directions for Energy Storage Systems

Batteries play a crucial role in the domain of energy storage systems and electric vehicles by enabling energy resilience, promoting renewable integration, and driving the advancement of eco-friendly mobility. However, the degradation of batteries over time remains a significant challenge. This paper presents a comprehensive review aimed at investigating the intricate phenomenon of battery degradation within the realm of sustainable energy storage systems and electric vehicles (EVs). This review consolidates current knowledge on the diverse array of factors influencing battery degradation mechanisms, encompassing thermal stresses, cycling patterns, chemical reactions, and environmental conditions. The key degradation factors of lithium-ion batteries such as electrolyte breakdown, cycling, temperature, calendar aging, and depth of discharge are thoroughly discussed. Along with the key degradation factor, the impacts of these factors on lithium-ion batteries including capacity fade, reduction in energy density, increase in internal resistance, and reduction in overall efficiency have also been highlighted throughout the paper. Additionally, the data-driven approaches of battery degradation estimation have taken into consideration. Furthermore, this paper delves into the multifaceted impacts of battery degradation on the performance, longevity, and overall sustainability of energy storage systems and EVs. Finally, the main drawbacks, issues and challenges related to the lifespan of batteries are addressed. Recommendations, best practices, and future directions are also provided to overcome the battery degradation issues towards sustainable energy storage system.

Electrode and Electrolyte Co-Energy-Storage Electrochemistry Enables High-Energy Zn-S Decoupled Batteries.

In the search for next-generation green energy storage solutions, Cu-S electrochemistry has recently gained attraction from the battery community owing to its affordability and exceptionally high specific capacity of 3350mAhgs -1. However, the inferior conductivity and substantial volume expansion of the S cathode hinder its cycling stability, while the low output voltage limits its energy density. Herein, a hollow carbon sphere (HCS) is synthesized as a 3D conductive host to achieve a stable S@HCS cathode, which enables an outstanding cycling performance of 2500 cycles (over 9 months). To address the latter, a Zn//S@HCS alkaline-acid decoupled cell is configured to increase the output voltage from 0.18 to 1.6V. Moreover, an electrode and electrolyte co-energy storage mechanism is proposed to offset the reduction in energy density resulting from the extra electrolyte required in Zn//S decoupled cells. When combined, the Zn//S@HCS alkaline-acid decoupled cell delivers a record energy density of 334Whkg-1 based on the mass of the S cathode and CuSO4 electrolyte. This work tackles the key challenges of Cu-S electrochemistry and brings new insights into the rational design of decoupled batteries.

Preparation of Sea Urchin‐Like Co/Ni Alloy Compounds for Pseudocapacitive Supercapacitor

Energy density and power density are the two most crucial metrics in advanced electrochemical energy storage (EES) devices. The design of pseudocapacitor materials with good structure and reasonable composition can ensure that the power density can be greatly increased under the condition of little or no reduction in energy density. However, how to reasonably design excellent pseudocapacitor materials is still a huge challenge. Herein, layered double hydroxides containing Ni and Co elements on carbon materials derived from distillers’ grains by hydrothermal synthesis (NiCo‐LDH/JKPC‐2) are grown. The fabricated NiCo‐LDH/JKPC‐2 has exhibited a sea urchin‐like nanostructure that primarily consists of mesoporous and possesses a high specific surface area (303 m2 g−1), which facilitates the formation of larger active sites, thereby increasing the rate of charge transport. The specific capacitance of the NiCo‐LDH/JKPC‐2 reaches a maximum value of 1454 F g−1 at 1 A g−1. When it combines with carbon materials originating from distillers’ grains, the assembled asymmetric supercapacitor electrode exhibits a remarkable energy density (40.86 Wh kg−1 at 775 W kg−1) and superior power density (7750.8 W kg−1 at 21.53 Wh kg−1). Thus, the NiCo‐LDH/JKPC‐2 asymmetric supercapacitor electrode can be considered as a potential candidate in advanced energy storage device systems.

Low mass loading of graphene quantum dots on titanium nitride nanotube arrays for boosting capacity and operating voltage of symmetric supercapacitor in an aqueous electrolyte

Compared to other supercapacitors, aqueous supercapacitors offer reliability, a long lifecycle, and affordability. However, the significant challenge in advancing aqueous supercapacitors lies in their limited operating voltage window. This limitation has resulted in a notable reduction in energy density. Therefore, contemporary electrode materials exhibiting high electrochemical activity and wide operating potential windows are imperative. This study introduces a technique that not only boosts energy density but also signifies a significant breakthrough for metal nitride-based aqueous supercapacitors. This method broadens the operating voltage range and necessitates optimization of the heterostructure design. A distinctive titanium nitride/graphene quantum dot (TiN/GQD) heterostructure was synthesized through electrophoretic deposition of GQDs onto plasma-nitrided TiO2 nanotubes. This novel heterostructure demonstrates the capability to function across an extended voltage range of 2 V. It is noteworthy that the TiN/GQD nanocomposite has excellent bonding at the interface of TiOC and a large surface area, resulting in an exceptional areal capacitance of 190 mF cm−2 at a current density of 0.2 mA cm−2 in 0.5 M Na2SO4 aqueous solution. It also displays excellent cycle stability (91.5 % after 6000 galvanostatic charge-discharge cycles). Moreover, the optimum GQDs deposition time (15 min) was determined to achieve the most efficient electrochemical performance. Furthermore, a symmetric TiN/GQD-15 supercapacitor device was assembled, reaching a high energy density of 8.2 Wh kg−1 at a power density of 77 W kg−1.

Effect of mixing at weaning and nutrient density of the weaner diet on growth performance and welfare of pigs to slaughter

BackgroundMixing pigs at weaning can compromise pig welfare and growth. Therefore, grouping littermates together may allow a diet nutrient and energy density reduction during the nursery period to reduce feed cost without affecting slaughter weight. This study investigated the combined effect of mixing and reducing dietary energy and nutrient density on growth performance, body lesions (BL), and behaviour in pigs from weaning to slaughter.ResultsForty-eight litters [554 pigs, 11–12 pigs/litter; Danish Duroc × (Large White × Landrace)] were included in the trial. At 28 days of age, pigs were weaned and housed in nursery rooms in litter groups (INTACT, n = 24) or mixed with other litters and grouped by weight to reduce within-pen pig weight variation (MIXED, n = 24). A dietary regimen meeting pigs’ nutritional requirements (CON) and a low-density dietary regimen (LOW; -10% energy and protein) completed a 2 × 2 factorial arrangement (Mixing x Diet, n = 12). On day 74 of age, pigs moved to the grower-finisher accommodation without further mixing and all pigs received the CON dietary regimen. Mixing increased FCR by 4.0% during the nursery period (p = 0.003). Nursery pigs fed LOW experienced a growth retardation which was maintained until slaughter (-2.6 kg slaughter weight; p = 0.025). Initial differences in the coefficient of variation (CV) between MIXED (10.4%) and INTACT (17.6%; p < 0.001) pigs were reduced in CON pens but not in LOW pens (interaction p = 0.025) at the end of the nursery period. MIXED pigs had more fights and BL (p < 0.001) at weaning and showed more aggression (p = 0.003) after being moved to the grower-finisher rooms. At the end of the nursery period, MIXED pigs fed LOW showed the highest number of aggressive behaviours around the feeder (interaction; p = 0.003) and pigs fed LOW showed more damaging behaviour (p < 0.001).ConclusionsMixing animals at weaning had limited impact on growth performance but impaired welfare which was aggravated by energy and nutrient reduction in the nursery diet. Decreasing dietary nutrient density in the nursery stage retarded growth, which could not be compensated for during the growing-finishing period.

Impact of Fat Replacers on the Rheological, Tribological, and Aroma Release Properties of Reduced‐Fat Model Emulsion Systems and Processed Cheese

Impact of Fat Replacers on the Rheological, Tribological, and Aroma Release Properties of Reduced‐Fat Model Emulsion Systems and Processed Cheese

Enhancing the high-temperature energy storage performance of PEI dielectric film through deposition of high-dielectric PZT coating layer

Dielectric film capacitors are a highly ubiquitous and indispensable electronic component, serving a crucial role in a wide array of electronic devices and power systems. Despite their extensive use, polymer film capacitors are often hampered by the conduction loss that ensues when they are subjected to high electric fields and temperatures. As a result, this leads to a significant reduction in energy density and charge-discharge efficiency. To solve this issue, magnetron sputtering technology was used to create a sandwich structure made of polyetherimide (PEI) thin films with lead zirconate titanate (PZT) inorganic layers coated on both sides. This remarkable innovation has successfully introduced the high dielectric PZT layer in the PEI film/metal electrode, substantially augmenting the barrier height at the dielectric/polymer interface. This has also resulted in a marked decrease in conduction loss, as conclusively validated by the experimental findings. At 150 °C and with charge-discharge efficiency above 90%, the maximum discharged energy density is 3.26 J/cm3, which is increased by 263% compared to the pristine PEI films (1.24 J/cm3 at 290 MV/m and 150 °C). This study designed a unique inorganic barrier layer of PZT to increase the energy storage capability of polymer dielectric films in high-temperature environments.

Si-TiSi2 clusters eutectic nanoparticles as high initial coulombic efficiency anodes for lithium-ion batteries

The poor initial coulombic efficiency of silicon-based anode electrode is a major challenge hindering its practical application. In the initial cycle, the excessive consumption of lithium ions leads to significant reduction in energy density. Here, we propose a unique structure of eutectic nanoparticles containing TiSi2 clusters in the main phase of Si. The interaction between TiSi2 cluster and Si increases the lattice spacing of Si, reduces the lithium-ion insertion resistance and improves the initial coulombic efficiency of the electrode. The Si-TiSi2 clusters eutectic nanoparticles provide a high initial coulombic efficiency of 89.7% at 0.5 A g−1. This work provides a new enlightenment for high initial coulombic efficiency Si-based anodes.

Multi-objective optimization of pyroelectric thermal–electrical cycles

Pyroelectric thermal–electrical cycles enable a class of solid-state heat engines that convert waste heat to electrical energy. This article numerically investigates thermal-to-electrical energy conversion in a PbZr0.52Ti0.48O3 (PZT) pyroelectric layer near room temperature and optimizes operating parameters to maximize the electrical energy output. A general thermodynamic cycle is modeled after the prototypical pyroelectric Ericsson cycle—implemented based on the Ginzburg–Landau–Devonshire theory—with variable operating temperature range, and heating/cooling and charging/discharging time intervals. We used a Pareto optimization approach to simultaneously maximize electrical energy density and power density for different PZT sample and cycle parameters. The evaluated Pareto optimal fronts showcase the possibility of achieving multiple optimal solutions and highlight the trade-off between output energy density and power density in pyroelectric energy conversion. Specifically, we demonstrate that a 4× enhancement in power density is achievable with a less than 10% reduction in energy density for the same sample and operating conditions primarily by optimizing heat transfer. The multi-objective optimization approach and results presented in this study could provide a framework to facilitate the design and operation of pyroelectric cycles for waste heat energy harvesting systems.

Preparation and performance improvement of chlorides/MgO ceramics shape-stabilized phase change materials with expanded graphite for thermal energy storage system

Cold compression and mixed sintering methods have attracted attention for their applicability to industrial mass production. Due to the wettability of expanded graphite (EG) and salt chlorides, the decoupling of the encapsulation effect of EG and ceramics should be considered in the form-stable composite materials ratio of ternary chlorides (TC)/MgO ceramics/EG. In this study, 40 wt%-55 wt% MgO and 5 wt%-20 wt% EG are added to the composites, respectively. It is found that the composite system can be loaded with nearly 45 wt% molten salts. The 45 wt% TC-15 wt% EG-40 wt% MgO sample named 15EG-40MgO is considered a close to optimal formulation in terms of thermal conductivity enhancement and energy density reduction. This proportional composite has a thermal conductivity of 8.86 W∙m−1∙K−1, and in the temperature range of 300–600 °C, the thermal storage density reaches 439.53 J·g−1. With the increase of TC content, the density of the composites shows a decreasing trend. However, all samples have excellent mechanical strength due to the MgO ceramics as the supporting material. Moreover, these composites can be easily integrated into a solar thermal storage system, which proposes a new strategy for applying a high-temperature packed-bed containing salt-based composite phase change materials.

Development of high-voltage bipolar redox-active organic molecules through the electronic coupling of catholyte and anolyte structures.

All-organic non-aqueous redox flow batteries (O-NRFBs) are a promising technology for grid-scale energy storage. However, most examples of high-voltage (>2 V) O-NRFBs rely upon the use of distinct anolytes and catholytes separated by a membrane or porous separator which can result in crossover of redox active material from one side of the battery to the other. The resulting electrolyte mixing leads to irreversible reductions in energy density and capacity. A potentially attractive solution to overcome this crossover issue is the implementation of symmetric flow batteries where a single bipolar molecule functions as both an anolyte and a catholyte. Herein, we report the development of a new class of bipolar redox active materials for use in such symmetric flow batteries through the electronic coupling of phenothiazine catholytes and phthalimide anolytes. Such a strategy results in hybrid molecules possessing higher cell voltages than what could be obtained together by their uncoupled building blocks. Performance in flow batteries is demonstrated for two members of this new class of molecules, with the highest performing candidate featuring a ΔE of 2.31 V and demonstrating 93.6% average coulombic efficiency, 86.8% energy efficiency, and 68.6% capacity retention over the course of 275 charge-discharge cycles and 5 cell polarity reversals. Finally, the superior performance of symmetric O-NRFBs is experimentally confirmed by comparing these results to an asymmetric flow battery constructed with a distinct phenothiazine catholyte and a distinct phthalimide anolyte on opposing sides of the cell.

Densification, microstructure and properties of Sc and Zr modified Al-Mn alloy prepared by selective laser melting

In this work, the selective laser melting (SLM) of Sc and Zr modified Al-Mn alloy was systematically investigated, with a particular emphasis on the density behavior, microstructure and mechanical properties. The process parameters were significantly impact on the relative density and the maximum relative density of SLM-processed Al-Mn-Sc-Zr specimens reached 99.8% at the optimized process parameters. With the reduction of energy density, the melting mode of melting pool changed from keyhole mode to conduction mode. At the high energy density, near-spherical pores were generated because of the evaporation of low melting alloy constituents. With the decreasing of energy density, irregular pores were generated, which was mainly caused by the insufficient energy input. The SLM processed Al--Mn-Sc-Zr showed a duplex grain microstructure consisting of regions of columnar grains and equiaxed grains. Good mechanical properties were reached in as-fabricated condition: tensile strength ≥ 426 MPa and elongation to fracture ≥ 18%. Besides, no significant anisotropy was found in the stress–strain behavior between horizontal and vertical building direction.

Diffusion Enhancement to Stabilize Solid Electrolyte Interphase

AbstractThe damage of the solid electrolyte interphase (SEI) layer during the stripping process in lithium secondary batteries causes the reduction of energy density. The stabilization of the solid electrolyte interphase is as important as the inhibition of lithium dendrites for lithium‐based batteries. But the former is largely underestimated, which leads to the unclear damage mechanism and the lack of effective solutions to suppress the damage. Here, in this paper a diffusion‐limited damage mechanism of the SEI layer is proposed. The inhomogeneity of the SEI layer results in region‐dependent diffusion kinetics of lithium ions (Li+) passing through the layer. The slip lines and kinks having a thicker SEI layer, show slower Li+ conduction than the smooth surface. The uneven stripping process leads to the formation of cracks at the boundary between the slip lines and the smooth surface, which further causes collapse and serious damage of SEI. Upon this assumption, it is proposed to enhance the diffusion of Li+ at the local areas of SEI layer by applying parallel magnetic fields on the outside of electrodes. Both the electrochemical characterizations and long‐term stability examination confirm the effectiveness of the magnetic field in enhancing the diffusion of Li+ and suppressing the damage of SEI.

Characterization of two-way fabricated hybrid metal-oxide nanostructured electrode materials for photovoltaic and miniaturized supercapacitor applications

Portable electronic devices require a small volume self-powered energy system that can combine fabrication of energy harvesting and storage devices in one plane. This study focuses on fabricating novel all-oxide photovoltaic and supercapacitor devices based on MoO3, V2O5, and CoxOy thin electrodes prepared by a two-electrode cell arrangement. The fabricated devices were tested using solar simulator and potentiostat at ambient temperature. The power conversion efficiencies of the fabricated photovoltaic devices were found in the range of 0.17–0.39% depending on buffer layer characteristics. It therefore suggests that V2O5 and MoO3 can buffer photovoltaic processes by lowering the conduction band offset in the proximate CoxOy absorber. Pseudocapacitive behavior of MoO3/CoxOy||MoO3/CoxOy and V2O5/CoxOy||V2O5/CoxOy planar devices showed that they delivered maximum specific areal capacity values of 0.694 and 0.778 μAhcm−2 respectively at discharge current density of 0.1 mAcm−2. They also showed considerably low reduction in energy density (about 38.7%) even at a remarkable increase in power density of about 450% (at a high current density of 1.0 mAcm−2). In addition, the symmetric microsupercapacitors showed excellent retention of capacity even after 5000 cycles. These results generally indicate the reliability of the fabricated devices in the development of portable electronic components for energy application.

Infants Compensate Energy Intake Fully for Modest Reduction in Energy Density of Formula

Infants Compensate Energy Intake Fully for Modest Reduction in Energy Density of Formula

The hypervelocity impact resistance behaviors of NbC/Al2024 ceramic-metal composites

In this paper, the experiments of projectiles with hypervelocity impact on Whipple shields with Al2024 and NbC/Al2024 ceramic-metal composites as bumper respectively were carried out by using two-stage light-gas gun, and the movement process of debris cloud was recorded through laser shadow photography camera. The hypervelocity impacts of NbC/Al2024 Whipple shield were simulated, and there was good qualitative agreement between the simulations and experiments. The rear wall damage of Whipple shield and motion characteristics of debris clouds induced by projectile impacting on Al2024 bumper and NbC/Al2024 bumper were analyzed by experiment and numerical simulation results. The damage processes and material damage state of NbC/Al2024 bumper induced by projectile impact were analyzed. The results show that the NbC/Al2024 bumper can reduce the velocity of debris cloud and increase the impact area of debris cloud on the rear wall, resulting in the reduction of energy density on the rear wall caused by debris cloud impact. Because the NbC/Al bumper can increase the shock wave pressure within projectile, the projectile can be shattered into smaller fragments, and more projectile materials will melt and vaporized. As a result, the NbC/Al2024 ceramic-metal composites can reduce the damage of the debris cloud to the rear wall and enhance the protective capability of the Whipple shield.

The Effects of Watermelon Rind Flour on the Functional and Proximate Properties of Wheat Bread

The present study was undertaken to develop bread from composite flours. Composite flours were prepared by blending wheat flour with watermelon rind flour in ratios of 100:0 (AB1), 90:10 (AB2), 80:20 (AB3), 70:30 (AB4) and 60:40 (AB5), respectively. This study was carried out to ascertain the effects of watermelon rind flour at different replacement levels (0%, 10%, 20%, 30%, 40%) on the proximate and functional properties of composite wheat bread. The results of proximate properties determination on wheat/flour blend gave low bulk densities of 0.54g/cm3 to 0.60g/cm3, high water absorption capacity of 2.389 to 3.044 g/g as well as a high swelling capacity of 5.764 to 7.610 g/g and a low oil absorption capacity of 1.608 to 2.150 g/g. The results of proximate composition of composite bread revealed an increase in % protein, % carbohydrate and % ash from 15.7% to 18.8%, 47.1% to 52.0% and 0.6% to 1.2% respectively and a subsequent decrease in % fat from 18.4% to 13.8. There was a reduction in energy density for composite bread. The functional properties of composite flours such as swelling capacity, water absorption capacity, oil absorption capacity and bulk density were increased with increase in the incorporation of watermelon rind flour with wheat flour. Thus, the results indicate that by incorporating watermelon rind flour, it is possible to enhance the nutritional quality, chemical and functional properties of bread.

Towards better understanding of hyperbaric fiber laser spot welding of metallic material

The effect of hyperbaric environment on fiber laser spot welding (LW) of 304 stainless steel was explored. The laser power was 3 kW, the welding time was 0.2 s, and the defocus distance was 0 mm. When ambient pressure rose from 1 to 18 standard atmospheric pressures (atm): the intensity of spectrum signals of plasma above molten pool increased; the number of nano-sized metallic particles inside the beam path grew; in the initial stage of welding, the growth rates of the depth of molten pool and the height of plasma plumes separately reduced to be about 9.1 % and 40 % of those under 1 atm; the weld penetration was decreased to 20 % of that under 1 atm; on condition that the ambient pressure rose to 12 atm from 1 atm, the size of plasma plumes and the intensity of spectrum signals from plasma increased while the weld penetration declined. The main physical mechanism causing reduction of energy density when laser beams went through beams of nano-sized metallic particles was the absorption effect of nano-sized particles rather than their scattering effect. The results also showed that plasma plumes decreased after applying side assisting gas (AS) flow, and they were obviously deviated from the laser beam path, thus increasing the weld penetration to some extent.

New hybrid redox flow battery with high energy density using V–Mn/V–Mn multiple redox couples

A new hybrid redox flow V–Mn/V–Mn battery is introduced for enhancing the energy density of a V/V system. The energy density of the V–Mn/V–Mn system is high because the system has multiple redox reactions involving both V and Mn ions, and the operating cell potential increases owing to the high standard potential of the Mn(II)/Mn(III) reaction. Consequently, the discharge energy density is increased by 66.8% compared with that of the V/V system. Additionally, because the V–Mn/V–Mn system contains the same components in the negative and positive electrolytes, a reduction in energy density due to ion crossover with cycling can be achieved through a rebalancing process. The V–Mn/V–Mn system is not simply a mixture of V and Mn electrolytes but has a unique advantage. The presence of V ions reduces the particle size of the MnO2 produced by the disproportionation reaction during the charging process. The small MnO2 particles can flow into the cell together with the electrolyte and can be reduced to Mn ions. As a result, the reversibility and durability of the system are greatly improved. Therefore, the V–Mn/V–Mn system can complement the low energy density of the V/V system.

Analysis of Dissipative Losses in Modular Reconfigurable Energy Storage Systems Using SystemC TLM and SystemC-AMS

Battery storage systems are becoming more popular in the automotive industry as well as in stationary applications. To fulfill the requirements in terms of power and energy, the literature is increasingly discussing electrically reconfigurable interconnection topologies. However, these topologies use switching elements on the cell and module level that exhibit an electric resistance due to their design and hence generate undesirable dissipative losses. In this article, we propose a new analysis and optimization framework to examine and minimize the losses in such topologies. For this purpose, we develop a SystemC model to investigate static and dynamic load scenarios, e.g., from the automotive domain. The model uses SystemC TLM for the digital subsystem, SystemC-AMS for the mixed-signal subsystem, and host-compiled simulation for the microcontroller executing the embedded software. Here, we analyze the impact of the dissipative losses on the system efficiency that depend on the modularization level, implying the number of serial and parallel switching elements. Our analysis clearly shows that in reconfigurable topologies, the modularization level has a significant influence on the losses, which in our automotive example covers several orders of magnitude. For the topologies we have investigated, the highest efficiency can be reached when a parallel-only modularization is aspired and the number of serial switching elements is minimized. It is also shown that the losses of the state-of-the-art topology with one battery pack protection switch are almost as high as in a smart cell approach in which each energy storage cell has its own switching element. However, due to the high number of switching elements, this results in a reduction of energy density and increases the system costs, showing that this is a multi-criteria optimization problem.