Pub Date : 2023-08-02DOI: 10.1088/2515-7655/ace930
A. Fujita, K. Imaizumi
The magnetocaloric effect (MCE) in La1−z R z (Fe0.89−x Mn x Si0.11)13H y max (R = Ce and Pr) is verified in view of correlation between alloying recipes such as selection of doping elements and fundamental physics that governs MCE. The Ce-doped specimen with z = 0.3 & x = 0.017 exhibits a peaky isothermal entropy change ΔS M profile with a maximum value of 20 J kg−1 K under a field change of 0.8 T at the Curie temperature of 285 K. In contrast, the enlarged field dependence of the Curie temperature and diminished hysteresis results in the adiabatic temperature change ΔT ad of 2.7 K under a field change of 0.8 T at the Curie temperature of 289 K for the Pr-doped specimen.
从掺杂元素的选择等合金配方与控制MCE的基本物理之间的相关性出发，验证了La1−z Rz（Fe0.89−x Mn x Si0.11）13H y max（R=Ce和Pr）中的磁热效应（MCE）。z=0.3&x=0.017的Ce掺杂样品在285K的居里温度下，在0.8T的场变化下表现出峰值等温熵变Δ，居里温度的场依赖性增大和磁滞减小导致Pr掺杂样品在289K的居里温度下在0.8T的场变化下2.7K的绝热温度变化Δ。
{"title":"Magnetocaloric properties in (La,R)(Fe,Mn,Si)13H (R = Ce and Pr)—toward a better alloy design that results in a reduction in volume of permanent magnets and the establishment of long-term reliability in cooling systems","authors":"A. Fujita, K. Imaizumi","doi":"10.1088/2515-7655/ace930","DOIUrl":"https://doi.org/10.1088/2515-7655/ace930","url":null,"abstract":"The magnetocaloric effect (MCE) in La1−z R z (Fe0.89−x Mn x Si0.11)13H y max (R = Ce and Pr) is verified in view of correlation between alloying recipes such as selection of doping elements and fundamental physics that governs MCE. The Ce-doped specimen with z = 0.3 & x = 0.017 exhibits a peaky isothermal entropy change ΔS M profile with a maximum value of 20 J kg−1 K under a field change of 0.8 T at the Curie temperature of 285 K. In contrast, the enlarged field dependence of the Curie temperature and diminished hysteresis results in the adiabatic temperature change ΔT ad of 2.7 K under a field change of 0.8 T at the Curie temperature of 289 K for the Pr-doped specimen.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44991447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-27DOI: 10.1088/2515-7655/aceb1b
Stefan Mönch, K. Bartholomé
In an all-solid-state electrocaloric arrangement, an absolute temperature change which exceeds twice the electrocaloric adiabatic temperature change is locally realized, using just the distributed thermal capacitances and resistances and spatio-temporal distributed electric field control. First, simulations demonstrate surface temperature changes up to four times (400%) the electrocaloric adiabatic temperature change for several implementations of all-solid state distributed element configurations. Then, experimentally, an all-solid-state assembly is built from commercial electrocaloric capacitors with two independently-controlled parts, and the measured surface temperature change was 223% of the adiabatic electrocaloric temperature change, which clearly exceeds twice the adiabatic temperature change and verifies the practical feasibility of the approach. This allows a significant increase of the maximum temperature difference per stage in cascaded and thermal switch-based electrocaloric heat pumps, which was previously limited by the adiabatic electrocaloric temperature change (100%) under no-load conditions. Distributed thermal element simulations provide insight in the spatio-temporal temperatures within the all-solid-state electrocaloric element. Since only the distributed thermal capacitance and resistance is used to boost the temperature change, the maximum absolute temperature change occurs only in parts of the all-solid-state element, for example close to the surfaces. A trade-off of the approach is that the required electrocaloric capacitance increases more than the gained boost of the absolute temperature change, reducing the power density and electrical efficiency in heat pump systems. Nevertheless, the proposed approach enables to simplify electrocaloric heat pumps or to increasing the achievable temperature span, and might also improve other electrocaloric applications.
{"title":"Spatio-temporal solid-state electrocaloric effect exceeding twice the adiabatic temperature change","authors":"Stefan Mönch, K. Bartholomé","doi":"10.1088/2515-7655/aceb1b","DOIUrl":"https://doi.org/10.1088/2515-7655/aceb1b","url":null,"abstract":"In an all-solid-state electrocaloric arrangement, an absolute temperature change which exceeds twice the electrocaloric adiabatic temperature change is locally realized, using just the distributed thermal capacitances and resistances and spatio-temporal distributed electric field control. First, simulations demonstrate surface temperature changes up to four times (400%) the electrocaloric adiabatic temperature change for several implementations of all-solid state distributed element configurations. Then, experimentally, an all-solid-state assembly is built from commercial electrocaloric capacitors with two independently-controlled parts, and the measured surface temperature change was 223% of the adiabatic electrocaloric temperature change, which clearly exceeds twice the adiabatic temperature change and verifies the practical feasibility of the approach. This allows a significant increase of the maximum temperature difference per stage in cascaded and thermal switch-based electrocaloric heat pumps, which was previously limited by the adiabatic electrocaloric temperature change (100%) under no-load conditions. Distributed thermal element simulations provide insight in the spatio-temporal temperatures within the all-solid-state electrocaloric element. Since only the distributed thermal capacitance and resistance is used to boost the temperature change, the maximum absolute temperature change occurs only in parts of the all-solid-state element, for example close to the surfaces. A trade-off of the approach is that the required electrocaloric capacitance increases more than the gained boost of the absolute temperature change, reducing the power density and electrical efficiency in heat pump systems. Nevertheless, the proposed approach enables to simplify electrocaloric heat pumps or to increasing the achievable temperature span, and might also improve other electrocaloric applications.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42193616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-20DOI: 10.1088/2515-7655/ace92f
M. Quercio, Francesco Galbusera, A. Canova, A. Demir, G. Gruosso, B. Previtali
Ferromagnetic materials are used in various applications such as rotating electrical machines, wind turbines, electromagnetic shielding, transformers, and electromagnets. Compared to hard magnetic materials, their hysteresis cycles are featured by low values of coercive magnetic field and high permeability. The application of additive manufacturing to ferromagnetic materials is gaining more and more attraction. Indeed, thanks to a wider geometrical freedom, new topological optimized shapes for stator/rotor shapes can be addressed to enhance electric machines performances. However, the properties of the laser powder bed fusion (LPBF) processed alloy compared to conventionally produced counterpart must be still addressed. Accordingly, this paper presents for the first time the use of the LPBF for the manufacturing of Fe2.9wt.%Si electromagnetic shields. The process parameter selection material microstructure and the magnetic shielding factor are characterized.
{"title":"Electromagnetic shielding properties of LPBF produced Fe2.9wt.%Si alloy","authors":"M. Quercio, Francesco Galbusera, A. Canova, A. Demir, G. Gruosso, B. Previtali","doi":"10.1088/2515-7655/ace92f","DOIUrl":"https://doi.org/10.1088/2515-7655/ace92f","url":null,"abstract":"Ferromagnetic materials are used in various applications such as rotating electrical machines, wind turbines, electromagnetic shielding, transformers, and electromagnets. Compared to hard magnetic materials, their hysteresis cycles are featured by low values of coercive magnetic field and high permeability. The application of additive manufacturing to ferromagnetic materials is gaining more and more attraction. Indeed, thanks to a wider geometrical freedom, new topological optimized shapes for stator/rotor shapes can be addressed to enhance electric machines performances. However, the properties of the laser powder bed fusion (LPBF) processed alloy compared to conventionally produced counterpart must be still addressed. Accordingly, this paper presents for the first time the use of the LPBF for the manufacturing of Fe2.9wt.%Si electromagnetic shields. The process parameter selection material microstructure and the magnetic shielding factor are characterized.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47012603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-18DOI: 10.1088/2515-7655/ace850
José Miguel Ramos-Fajardo, Isabel María Peláez-Tirado, Juan Ramón Marín-Rueda, M. Castro-García, J. Canales‐Vázquez, J. Pérez-Flores
Carbon coated-LiFePO4 (LFP) is a strong candidate as lithium-ion battery (LiB) cathode due to the combination of safe operation, stable electrochemical performance and positive environmental impact as does not depend on Co, which is toxic and a critical raw material. In this work, we report the development of binder-free LFP cathodes fabricated by fused filament fabrication (FFF) technology. Several novel carbon-LFP filaments have been developed to 3D-print LiB cathodes, analysing both the carbon to LFP ratio in the formulation and also the impact of the carbon source used as current collector, i.e. glassy carbon (GC) microspheres or carbon black (CB), in the electrochemical performance. LFP remained stable upon debinding and sintering at temperatures as low as 500 °C as determined by x-ray diffraction. The conductivity of 3D printed LFP monoliths was 2.06 × 10−4 S∙cm−1 at 50 °C, which is fairly close to that of LFP produced via conventional processing. This is mainly attributed to the preservation of the carbon coating around the LFP particles after debinding and sintering under controlled Ar atmospheres. The LFP-based electrodes containing CB or GC microspheres as conductive additives exhibited specific capacities of 150 mAh g−1, and over 95% coulombic efficiency after 100 cycles, showing no significant performance losses. These results largely exceed the performances reported for previous LFP-based electrodes produced via FFF as the non-active binder is removed upon fabrication.
碳涂层LiFePO4（LFP）是锂离子电池（LiB）阴极的有力候选者，因为它具有安全操作、稳定的电化学性能和积极的环境影响，不依赖于有毒的关键原材料Co。在这项工作中，我们报道了通过熔融丝制造（FFF）技术制造的无粘合剂LFP阴极的发展。已经开发了几种新型的碳LFP细丝来3D打印LiB阴极，分析了配方中的碳与LFP的比例，以及用作集电器的碳源（即玻璃碳（GC）微球或炭黑（CB））对电化学性能的影响。根据x射线衍射测定，LFP在低至500°C的温度下脱粘和烧结后保持稳定。3D打印LFP单片在50°C时的电导率为2.06×10−4 S∙cm−1，与传统工艺生产的LFP相当接近。这主要归因于在受控的Ar气氛下脱粘和烧结后LFP颗粒周围的碳涂层的保留。含有CB或GC微球作为导电添加剂的LFP基电极在100次循环后显示出150 mAh g−1的比容量和超过95%的库仑效率，没有显示出显著的性能损失。这些结果大大超过了先前报道的通过FFF生产的LFP基电极的性能，因为在制造时去除了非活性粘合剂。
{"title":"LFP-based binder-free electrodes produced via fused filament fabrication","authors":"José Miguel Ramos-Fajardo, Isabel María Peláez-Tirado, Juan Ramón Marín-Rueda, M. Castro-García, J. Canales‐Vázquez, J. Pérez-Flores","doi":"10.1088/2515-7655/ace850","DOIUrl":"https://doi.org/10.1088/2515-7655/ace850","url":null,"abstract":"Carbon coated-LiFePO4 (LFP) is a strong candidate as lithium-ion battery (LiB) cathode due to the combination of safe operation, stable electrochemical performance and positive environmental impact as does not depend on Co, which is toxic and a critical raw material. In this work, we report the development of binder-free LFP cathodes fabricated by fused filament fabrication (FFF) technology. Several novel carbon-LFP filaments have been developed to 3D-print LiB cathodes, analysing both the carbon to LFP ratio in the formulation and also the impact of the carbon source used as current collector, i.e. glassy carbon (GC) microspheres or carbon black (CB), in the electrochemical performance. LFP remained stable upon debinding and sintering at temperatures as low as 500 °C as determined by x-ray diffraction. The conductivity of 3D printed LFP monoliths was 2.06 × 10−4 S∙cm−1 at 50 °C, which is fairly close to that of LFP produced via conventional processing. This is mainly attributed to the preservation of the carbon coating around the LFP particles after debinding and sintering under controlled Ar atmospheres. The LFP-based electrodes containing CB or GC microspheres as conductive additives exhibited specific capacities of 150 mAh g−1, and over 95% coulombic efficiency after 100 cycles, showing no significant performance losses. These results largely exceed the performances reported for previous LFP-based electrodes produced via FFF as the non-active binder is removed upon fabrication.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44322936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-17DOI: 10.1088/2515-7655/ace7f5
Tal Binyamin, Orit Cohen, Idan Cohen, L. Etgar
Organic ligands play a crucial role in the properties and functionality of nanostructures. Functional ligands are an interesting research direction that can be utilized to influence the properties and functionality of nanoparticles (NPs). In this work, we demonstrate controlled assembly of CsPbBr3 perovskite NPs as a result of light. Azobenzene derivative molecules were used as the photoswitchable ligands for the NPs. The assembly and disassembly of the NPs were achieved by cis–trans isomerization. By utilizing polarization-modulated, infrared reflection–absorption spectroscopy and diffusion-ordered nuclear magnetic resonance, we were able to track the attachment of the ligands to the surface of the NPs. Absorbance, photoluminescence and high-resolution, transmission electron microscopy followed the assembly and disassembly of the NPs. This work demonstrates functional ligands paired to perovskite nanostructures through controlling their assembly and disassembly, which opens the way for sensing and photodetection applications.
{"title":"Controlled assembly of perovskite nanoparticles by photoswitchable functional ligands","authors":"Tal Binyamin, Orit Cohen, Idan Cohen, L. Etgar","doi":"10.1088/2515-7655/ace7f5","DOIUrl":"https://doi.org/10.1088/2515-7655/ace7f5","url":null,"abstract":"Organic ligands play a crucial role in the properties and functionality of nanostructures. Functional ligands are an interesting research direction that can be utilized to influence the properties and functionality of nanoparticles (NPs). In this work, we demonstrate controlled assembly of CsPbBr3 perovskite NPs as a result of light. Azobenzene derivative molecules were used as the photoswitchable ligands for the NPs. The assembly and disassembly of the NPs were achieved by cis–trans isomerization. By utilizing polarization-modulated, infrared reflection–absorption spectroscopy and diffusion-ordered nuclear magnetic resonance, we were able to track the attachment of the ligands to the surface of the NPs. Absorbance, photoluminescence and high-resolution, transmission electron microscopy followed the assembly and disassembly of the NPs. This work demonstrates functional ligands paired to perovskite nanostructures through controlling their assembly and disassembly, which opens the way for sensing and photodetection applications.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44334832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-17DOI: 10.1088/2515-7655/ace7f4
J. Schipper, D. Bach, Stefan Mönch, C. Molin, S. Gebhardt, J. Woellenstein, Olaf Schaefer-Welsen, C. Vogel, R. Langebach, K. Bartholomé
Efficiency improvements in heat pump can drastically reduce global energy demand. Caloric heat pumps are currently being investigated as a potentially more efficient alternative to vapor compression systems. Caloric heat pumps are driven by solid-state materials that exhibit a significant change in temperature when a field is applied, such as a magnetic or an electric field as well as mechanical stress. For most caloric materials, the phase transition results in a certain amount of power dissipation, which drastically impacts the efficiency of a caloric cooling system. The impact on the efficiency can be expressed by a figure of merit (FOM), which can directly be deduced from material properties. This FOM has been derived for 36 different magneto-, elasto-, electro and barocaloric material classes based on literature data. It is found that the best materials can theoretically attain second law efficiencies of over 90%. The FOM is analogous to the isentropic efficiency of idealized compressors of vapor compression systems. The isentropic efficiency can thus be directly linked to the theoretically achievable efficiency of a compressor-based refrigeration system for a given refrigerant. In this work a theoretical comparison is made between efficiency of caloric heat pumps and vapor compression systems based on the material losses for the caloric heat pump and the efficiency of the compressor for vapor compression systems. The effect of heat regeneration is considered in both cases. In vapor compression systems, the effect of the working fluid on the efficiency is also studied.
{"title":"On the efficiency of caloric materials in direct comparison with exergetic grades of compressors","authors":"J. Schipper, D. Bach, Stefan Mönch, C. Molin, S. Gebhardt, J. Woellenstein, Olaf Schaefer-Welsen, C. Vogel, R. Langebach, K. Bartholomé","doi":"10.1088/2515-7655/ace7f4","DOIUrl":"https://doi.org/10.1088/2515-7655/ace7f4","url":null,"abstract":"Efficiency improvements in heat pump can drastically reduce global energy demand. Caloric heat pumps are currently being investigated as a potentially more efficient alternative to vapor compression systems. Caloric heat pumps are driven by solid-state materials that exhibit a significant change in temperature when a field is applied, such as a magnetic or an electric field as well as mechanical stress. For most caloric materials, the phase transition results in a certain amount of power dissipation, which drastically impacts the efficiency of a caloric cooling system. The impact on the efficiency can be expressed by a figure of merit (FOM), which can directly be deduced from material properties. This FOM has been derived for 36 different magneto-, elasto-, electro and barocaloric material classes based on literature data. It is found that the best materials can theoretically attain second law efficiencies of over 90%. The FOM is analogous to the isentropic efficiency of idealized compressors of vapor compression systems. The isentropic efficiency can thus be directly linked to the theoretically achievable efficiency of a compressor-based refrigeration system for a given refrigerant. In this work a theoretical comparison is made between efficiency of caloric heat pumps and vapor compression systems based on the material losses for the caloric heat pump and the efficiency of the compressor for vapor compression systems. The effect of heat regeneration is considered in both cases. In vapor compression systems, the effect of the working fluid on the efficiency is also studied.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":"5 1","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41346678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-17DOI: 10.1088/2515-7655/ace7f3
T. Hirai, K. Uto, M. Ebara, K. Uchida
Solid-state cooling/heating technology based on the elastocaloric effect is one of the promising alternatives to vapor compression systems. Large elastocaloric temperature modulation is often generated through the non-linear strain-induced structural transition by applying large strain and/or stress to ferroelastic materials. Recently, an unconventional approach to expand the application possibilities of the elastocaloric effect was demonstrated by processing elastocaloric materials into kirigami structures, which was inspired by the art of paper cutting. Using this approach, only a small stretch of processed conventional plastics can locally provide more efficient performance of elastocaloric temperature modulation than that of ferroelastic materials. To further improve such a unique functionality, it is necessary to find plastic or polymeric materials showing large elastocaloric effects in the linear elastic response regime that can be driven by a MPa-order weak stress application, where the non-linear structural transition is irrelevant. In this work, by means of a recently developed measurement technique for the elastocaloric effect based on the lock-in thermography, we found that shape memory polymers (SMPs) show prominent performance for elastocaloric temperature modulation that is larger than conventional plastics. SMPs enable the control of crystallinity by changing the cross-linking agents, melting temperature by changing the degree of polymerization, and orientation of the polymer chain segment by the shape memory effect. By utilizing the unique properties of SMPs, we manipulated their elastocaloric performance. The experimental results reported here will highlight the potential of smart polymers for flexible and durable elastocaloric applications.
{"title":"Elastocaloric effect of shape memory polymers in elastic response regime","authors":"T. Hirai, K. Uto, M. Ebara, K. Uchida","doi":"10.1088/2515-7655/ace7f3","DOIUrl":"https://doi.org/10.1088/2515-7655/ace7f3","url":null,"abstract":"Solid-state cooling/heating technology based on the elastocaloric effect is one of the promising alternatives to vapor compression systems. Large elastocaloric temperature modulation is often generated through the non-linear strain-induced structural transition by applying large strain and/or stress to ferroelastic materials. Recently, an unconventional approach to expand the application possibilities of the elastocaloric effect was demonstrated by processing elastocaloric materials into kirigami structures, which was inspired by the art of paper cutting. Using this approach, only a small stretch of processed conventional plastics can locally provide more efficient performance of elastocaloric temperature modulation than that of ferroelastic materials. To further improve such a unique functionality, it is necessary to find plastic or polymeric materials showing large elastocaloric effects in the linear elastic response regime that can be driven by a MPa-order weak stress application, where the non-linear structural transition is irrelevant. In this work, by means of a recently developed measurement technique for the elastocaloric effect based on the lock-in thermography, we found that shape memory polymers (SMPs) show prominent performance for elastocaloric temperature modulation that is larger than conventional plastics. SMPs enable the control of crystallinity by changing the cross-linking agents, melting temperature by changing the degree of polymerization, and orientation of the polymer chain segment by the shape memory effect. By utilizing the unique properties of SMPs, we manipulated their elastocaloric performance. The experimental results reported here will highlight the potential of smart polymers for flexible and durable elastocaloric applications.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42457503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1088/2515-7655/ace288
Nada Petelin, M. Kalin, A. Kitanovski
The quest for better performance from magnetocaloric devices has led to the development of thermal control devices, such as thermal switches, thermal diodes, and thermal capacitors. These devices are capable of controlling the intensity and direction of the heat flowing between the magnetocaloric material and the heat source or heat sink, and therefore have the potential to simultaneously improve the power density and energy efficiency of magnetocaloric systems. We have developed a new type of thermal control device, i.e., a silicon mechanical thermal switch capacitor ( TSC). In this paper we first review recently developed thermal switches based on micro-electromechanical systems and present the operation and structure of our new TSC. Then, the results of the parametric experimental study on the thermal contact resistance, as one of the most important parameters affecting the thermal performance of the device, are presented. These experimental data were later used in a numerical model for a magnetocaloric device with a thermal switch-capacitor. The results of the study show that for a single embodiment, a maximum cooling power density of 970 W m−2 (510 W kgmcm −1) could be achieved for a zero-temperature span and an operating frequency of 5 Hz. However, a larger temperature span could be achieved by cascading multiple magnetocaloric elements with TSCs. We have shown that the compact TSC can be used in caloric devices, even with small temperature variations, and can be used in a variety of practical applications requiring thermal regulation.
对磁热器件更好性能的追求导致了热控制器件的发展，如热开关、热二极管和热电容器。这些装置能够控制在磁热材料与热源或散热器之间流动的热量的强度和方向，因此具有同时提高磁热系统的功率密度和能量效率的潜力。我们开发了一种新型的热控制装置，即硅机械热开关电容器（TSC）。在本文中，我们首先回顾了最近开发的基于微机电系统的热开关，并介绍了我们新的TSC的操作和结构。然后，给出了影响器件热性能的最重要参数之一热接触电阻的参数实验研究结果。这些实验数据后来被用于具有热开关电容器的磁热器件的数值模型中。研究结果表明，对于单个实施例，在零温度范围和5 Hz的工作频率下，可以实现970 W m−2（510 W kgmcm−1）的最大冷却功率密度。然而，通过将多个磁热元件与TSC级联可以实现更大的温度跨度。我们已经证明，即使温度变化很小，紧凑型TSC也可以用于热量设备，并且可以用于需要热调节的各种实际应用。
{"title":"A conceptual design of a thermal switch capacitor in a magnetocaloric device: experimental characterization of properties and simulations of operating characteristics","authors":"Nada Petelin, M. Kalin, A. Kitanovski","doi":"10.1088/2515-7655/ace288","DOIUrl":"https://doi.org/10.1088/2515-7655/ace288","url":null,"abstract":"The quest for better performance from magnetocaloric devices has led to the development of thermal control devices, such as thermal switches, thermal diodes, and thermal capacitors. These devices are capable of controlling the intensity and direction of the heat flowing between the magnetocaloric material and the heat source or heat sink, and therefore have the potential to simultaneously improve the power density and energy efficiency of magnetocaloric systems. We have developed a new type of thermal control device, i.e., a silicon mechanical thermal switch capacitor ( TSC). In this paper we first review recently developed thermal switches based on micro-electromechanical systems and present the operation and structure of our new TSC. Then, the results of the parametric experimental study on the thermal contact resistance, as one of the most important parameters affecting the thermal performance of the device, are presented. These experimental data were later used in a numerical model for a magnetocaloric device with a thermal switch-capacitor. The results of the study show that for a single embodiment, a maximum cooling power density of 970 W m−2 (510 W kgmcm −1) could be achieved for a zero-temperature span and an operating frequency of 5 Hz. However, a larger temperature span could be achieved by cascading multiple magnetocaloric elements with TSCs. We have shown that the compact TSC can be used in caloric devices, even with small temperature variations, and can be used in a variety of practical applications requiring thermal regulation.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49325844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1088/2515-7655/acdf1d
Yide Li, Jie Li, Zhiyuan Liu, Zhangwei Chen, Changyong Liu
Thick electrodes with higher energy density are highly desirable for lithium-ion batteries (LIBs). However, the sluggish transport of Li-ions in thick electrodes is a critical challenge. In this study, a novel synchronously interdigitated/winded battery configuration enabled by 3D printing is proposed. The cathode, separator, and anode are synchronously interdigitated in the core and synchronously winded in the outer-rings to form an integrated full battery. With this novel battery configuration, Li-ions can transport between neighboring cathode and anode, thereby significantly reduce the transport distance of Li-ions, and improve the electrochemical reaction kinetics. To evaluate the electrochemical performance of this battery configuration, this study investigates the effects of various parameters including the electronic conductivity, electrode porosity, electrode line width, separator thickness, and number of winded outer-rings on the electrochemical performance through numerical simulations. Results showed that electronic conductivity is the most crucial factor in determining the electrochemical performance. In combination with multi-material 3D printing, the battery configuration proposed in this study may be utilized to build LIBs with higher energy density.
{"title":"Performance evaluation of a novel synchronously interdigitated/winded lithium-ion battery configuration enabled by 3D printing through numerical simulations","authors":"Yide Li, Jie Li, Zhiyuan Liu, Zhangwei Chen, Changyong Liu","doi":"10.1088/2515-7655/acdf1d","DOIUrl":"https://doi.org/10.1088/2515-7655/acdf1d","url":null,"abstract":"Thick electrodes with higher energy density are highly desirable for lithium-ion batteries (LIBs). However, the sluggish transport of Li-ions in thick electrodes is a critical challenge. In this study, a novel synchronously interdigitated/winded battery configuration enabled by 3D printing is proposed. The cathode, separator, and anode are synchronously interdigitated in the core and synchronously winded in the outer-rings to form an integrated full battery. With this novel battery configuration, Li-ions can transport between neighboring cathode and anode, thereby significantly reduce the transport distance of Li-ions, and improve the electrochemical reaction kinetics. To evaluate the electrochemical performance of this battery configuration, this study investigates the effects of various parameters including the electronic conductivity, electrode porosity, electrode line width, separator thickness, and number of winded outer-rings on the electrochemical performance through numerical simulations. Results showed that electronic conductivity is the most crucial factor in determining the electrochemical performance. In combination with multi-material 3D printing, the battery configuration proposed in this study may be utilized to build LIBs with higher energy density.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44960893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-01DOI: 10.1088/2515-7655/ace07b
T. Kirchartz, Basita Das
In many emerging solar cell technologies, it is a significant challenge to extract the electronic properties of materials and interfaces inside a working device from experimental data. In many cases, approaches frequently used in mature technologies such as crystalline silicon are inapplicable as they require many material parameters to be known a-priori, which is rarely the case for novel materials. Based on this challenge for material and device characterization, this perspective discusses the different strategies for data interpretation that have been developed or are in the process of being developed for the specific case of halide perovskite solar cells. The specific focus of this work is to discriminate between experimental data and strategies to extract useful information from data. This information can then be used to make informed decisions about strategies for process and material innovations.
{"title":"Transforming characterization data into information in the case of perovskite solar cells","authors":"T. Kirchartz, Basita Das","doi":"10.1088/2515-7655/ace07b","DOIUrl":"https://doi.org/10.1088/2515-7655/ace07b","url":null,"abstract":"In many emerging solar cell technologies, it is a significant challenge to extract the electronic properties of materials and interfaces inside a working device from experimental data. In many cases, approaches frequently used in mature technologies such as crystalline silicon are inapplicable as they require many material parameters to be known a-priori, which is rarely the case for novel materials. Based on this challenge for material and device characterization, this perspective discusses the different strategies for data interpretation that have been developed or are in the process of being developed for the specific case of halide perovskite solar cells. The specific focus of this work is to discriminate between experimental data and strategies to extract useful information from data. This information can then be used to make informed decisions about strategies for process and material innovations.","PeriodicalId":48500,"journal":{"name":"Journal of Physics-Energy","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46932244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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