{"title":"Development and investigation of biobased binary eutectic phase change materials for low-temperature building applications: 1-Hexadecanol/1-Dodecanol and 1-Octadecanol/1-Dodecanol","authors":"","doi":"10.1016/j.est.2024.114345","DOIUrl":"10.1016/j.est.2024.114345","url":null,"abstract":"<div><div>Phase change materials (PCMs) play a crucial role in optimizing thermal management in low-temperature buildings, contributing to reduced energy consumption and greenhouse gas emissions. This study aims to address the limitations of conventional paraffin-based PCM by developing binary mixtures of fatty alcohols. Through theoretical calculations, binary phase diagram fitting, and experimental validation, the thermal performance, phase transition behavior, and integration methods of these mixtures were thoroughly investigated using techniques such as differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The results showed that 1-dodecanol/1-tetradecanol (TD) mixtures were unsuitable for building applications due to their inability to form eutectic phases. However, two eutectic PCMs, namely HD82.44 (82.44 % 1-dodecanol/17.56 % 1-hexadecanol) and OD82.66 (82.66 % 1-dodecanol/17.34 % 1-octadecanol), were successfully synthesized. HD82.44 began melting at 16.4 °C, reached peak heat absorption at 19.6 °C and a melting latent heat of 193.7 J/g. Solidification started at 17.3 °C, with two exothermic peaks at 14.2 °C and 6.8 °C, and a freezing latent heat of 192.4 J/g. The solid and liquid specific heats were 2.02 J/(g·°C) and 2.56 J/(g·°C), respectively. OD82.66 began melting at 18.1 °C, with peak thermal effect at 21.4 °C. Solidification started at 23.1 °C, followed by a freezing peak at 15.1 °C. Both melting and freezing enthalpies were 206.4 J/g. Its solid and liquid specific heats were 2.02 J/(g·°C) and 2.67 J/(g·°C), respectively. Both PCM displayed no supercooling, suitable phase change temperatures, and high thermal storage properties, making them promising alternatives to traditional paraffin-based PCM for thermal energy storage in buildings. Additionally, FTIR analysis confirmed the physical integration of the binary fatty alcohol eutectic PCMs, while thermal cycling tests demonstrated their long-term stability.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"High-yield nitrogen-rich carbon electrode materials derived from Lentinula edodes for high-performance supercapacitors","authors":"","doi":"10.1016/j.est.2024.114350","DOIUrl":"10.1016/j.est.2024.114350","url":null,"abstract":"<div><div>Biomass-derived carbon is frequently used as a highly efficient material for supercapacitors. However, the low yield of biomass-derived carbon during pyrolysis limits its application range. In this study, a simple crosslinking strategy was employed to synthesize nitrogen-doped high-yield Lentinula edodes-derived carbon using urea–formaldehyde (UF) resin. The good compatibility of cellulose chains within Lentinula edodes and polymer chains within UF facilitated the formation of a stable structure during crosslinking. A high carbon yield of 36.09 % was achieved, which exceeded those of the individual components (9.58 % for Lentinula edodes and 22.09 % for UF resin) at the same conditions. Thus, benefited by the doping of N element originated from UF resin, the produced carbon material exhibited high electrochemical performance: its specific capacitance reached 375 F g<sup>−1</sup> at 0.5 A g<sup>−1</sup> (237.0 F g<sup>−1</sup> for Lentinula edodes carbon and 84.2 F g<sup>−1</sup> for UF resin carbon) with a 94.1 % capacitance retention after 10,000 cycles conducted at 5 A g<sup>−1</sup> (91.9 % for Lentinula edodes carbon and 92.0 % for UF resin carbon). Furthermore, the assembled symmetric supercapacitor demonstrated an energy density of 59.7 Wh kg<sup>−1</sup> at 900 W kg<sup>−1</sup>, and the capacitance retention of 102.3 % after 10,000 cycles conducted at 5 A g<sup>−1</sup>, indicating a high application potential in the field of energy storage.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Trends and insights into alloying elements impact on predicted battery voltage in metal-ion batteries","authors":"","doi":"10.1016/j.est.2024.114412","DOIUrl":"10.1016/j.est.2024.114412","url":null,"abstract":"<div><div>In recent years, metal-ion batteries have been the focus of extensive research. A significant challenge in utilizing certain ions, particularly multivalent ions, has been identifying suitable electrode materials. To address this, we developed a machine-learning model using LightGBM to predict the average voltage of metal-ion batteries based on electrode composition in the charged and discharged states. Our model achieved a prediction error of 0.26 V when benchmarked against several experimentally obtained values. Moreover, we provide key trends as to how the addition of alloying elements such as Manganese, Iron, Cobalt, Nickel, and Aluminium in the electrode affects the output voltage. Furthermore, by screening several thousands of novel electrode compositions obtained by alloying these elements, we provide a set of 12 compositions that are predicted to have an average voltage >4.5 V.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A novel low-energy and ultra-easy approach to preparing composite phase change material with high photo-/electro-thermal energy conversion and storage","authors":"","doi":"10.1016/j.est.2024.114373","DOIUrl":"10.1016/j.est.2024.114373","url":null,"abstract":"<div><div>Use of Phase Change Materials (PCM) for thermal energy storage has been a research hotspot in the field of energy storage. However, the development of composite PCM is always hindered by liquid leakage and poor photo-/electro-thermal conversion efficiency of PCM. In this work, inspired by the preparation of frozen tofu, a novel graphene foam (GF) was prepared by the method. Then polypyrrole (PPy) was successfully coated on the surface of GF by vapor phase deposition, to obtain GF@PPy. Finally, polyethylene glycol (PEG) was supported using GF@PPy, which effectively prevented the leakage of PEG, and successfully obtained a form-stable composite PCM (PEG/GF@PPy) with photo/electro-thermal conversion property. Research indicates that owing to the π-electrons in the molecular chain of PPy are freely movable, which endows PPy possess excellent electrical and thermal conductivity. It ultimately results in the introduction of PPy improve the thermal and electrical conductivity of composite PCM. It makes PEG/GF@PPy exhibit an effective electro-thermal conversion efficiency of 89.6 %. Moreover, PPy as an excellent photothermal conversion material, enhanced the photothermal conversion efficiency of PEG/GF@PPy up to 90.3 %. Finally, the composite PCM with photoelectric/electrical heat conversion property is applied to the field of thermotherapy. Comparison of popular thermotherapy products indicates that PEG/GF@PPy was able to provide longer duration of thermotherapy, up to 77.8 min. The strategy reported in this paper may assist in the preparation of composite PCM with high photo/electro-thermal conversion efficiency for use in the thermotherapy field.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Experimental study of the effect of cyclic and stepped temperature and flow rate change operations on the solid particle/thermal oil fin-tube heat exchanger","authors":"","doi":"10.1016/j.est.2024.114335","DOIUrl":"10.1016/j.est.2024.114335","url":null,"abstract":"<div><div>This study delves into the thermal performance of various cycles and operational strategies within the magnetite/heat transfer oil (HTO) tube-fin thermal energy storage (TES) system. In the initial cycle, longer charging times and higher charging energy/exergy rates are evident due to lower average temperatures. However, this performance gap diminishes in subsequent cycles. As cycles progress, temperature evolution within the TES unit (except bottom temperature) becomes more predictable, yet a thermal performance gap persists. Although these enhancements are irregular, energy and exergy efficiency improve each cycle. Specifically, energy efficiency increases by 15.0 % and 18.0 %, and exergy efficiency increases by 11.4 % and 13.4 % for Cycles 2 and 3, respectively, relative to Cycle 1. Adopting the stepped temperature change strategy results in extended charging/discharging times but yields a more gradual temperature variation and a stable energy/exergy rate. While this method amplifies energy dissipation and irreversible losses during charging, it minimizes entropy increase during discharging, enhancing exergy efficiency. The energy/exergy efficiencies for Cases 1, 2, and 3 are 83.7/62.8 %, 82.5/71.1 %, and 80.9/67.9 %, respectively. Similarly, implementing the stepped flow rate change strategy, particularly with a lower flow rate (Case 4), leads to slightly prolonged charging and discharging but results in smoother temperature changes and more stable energy/exergy rates. The energy/exergy efficiencies for Cases 4 and 5 are 85.7/65.2 % and 83.7/63.1 %, respectively. Although there exists a slight gap in the energy and exergy efficiencies among the three cases, the stepped flow rate change strategy ensures stable energy transfer and high efficiency. Overall, strategic thermal management is crucial for TES systems, and the findings can potentially advance the development of energy storage solutions for dynamic and flexible energy systems.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Transition metal nitride thin films used as the electrodes for lithium-ion batteries and supercapacitors","authors":"","doi":"10.1016/j.est.2024.114356","DOIUrl":"10.1016/j.est.2024.114356","url":null,"abstract":"<div><div>The transition metal nitride (TMN) thin films used as the electrodes for lithium-ion batteries (LIBs) and supercapacitors (SCs) have been completely reviewed and systematically discussed in this article. After the introduction of current research status, the energy storage mechanisms in TMN materials are first classified and interpreted. Next, the principles and characteristics of thin film fabrication techniques used to deposit the TMN thin film electrodes are briefly introduced. Then the research results of LIBs and SCs using the TMN thin film electrodes are individually reviewed and discussed in detail. The design considerations for the TMN thin film electrodes applied to LIBs and SCs are summarized according to the case studies. Eventually, it is concluded that the sputtering deposition would be the mainstream technique for the fabrication of thin film electrodes as well as the modification and/or combination of fabrication process may be utilized to improve the electrochemical performance of thin film electrodes. The potential candidates of TMN thin film electrodes for the future development of LIBs and SCs have been announced. The exploitation of solid-state electrochemical energy storage (EES) devices would be the future trend owing to the safety considerations.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improved State of Charge estimation of a Li-ion cell using a Fractional Order Model with hysteresis","authors":"","doi":"10.1016/j.est.2024.114114","DOIUrl":"10.1016/j.est.2024.114114","url":null,"abstract":"<div><div>Accurate State of Charge (SoC) estimation is a main function of Battery Management Systems (BMS) to ensure safety and good performance of Electric Vehicles (EVs). Lithium Ferro Phosphate (LFP) is one of the most preferred cell chemistry for EV and Hybrid Electric Vehicles (HEV) applications. The estimation of LFP cells is fraught with difficulties due to the presence of high hysteresis and the flat nature of SoC-OCV characteristics. To enhance the accuracy of the SoC estimate, this paper attempts to model LFP cells using a Fractional Order Model (FOM) and incorporate the dynamic hysteretic nature into the same model. An FOM is able to capture the battery dynamics over the entire frequency range of interest better than the conventional Integer Order Model (IOM). To build the FOM at first, EIS tests are performed at varying SoC levels to obtain the complex impedance function of frequency. Then, an FOM-based Equivalent Circuit Model (ECM) is obtained from the impedance data from the EIS test using Levenberg–Marquardt (LM) Algorithm. The hysteresis effect is captured as a non-linear state dynamic characterised by a decay rate parameter. A novel method for estimating the hysteresis decay rate parameter, independent of ECM, is proposed and implemented using DEKF. The overall model is validated using voltage-current data for standard drive cycles like UDDS and NEDC. The model is compared against those using an FOM with a switched hysteresis model, an Integer Order Model (IOM) with a dynamic hysteresis model, and an IOM with a switched hysteresis model with laboratory test data. The estimation accuracy is observed to be considerably and consistently better for the proposed model, even under different ambient temperatures with a Mean Absolute Error of less than 1.5%. Such improvements will, in turn, lead to improvements in various EV functions such as the estimation of Electric Range, Remaining Useful Life as well as Energy Management.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tunable N-F-O tri-doped flexible hierarchical porous carbon nanofibers derived from electrospun PVP/PTFE nanofibers towards high electrochemical performance for energy storage","authors":"","doi":"10.1016/j.est.2024.114358","DOIUrl":"10.1016/j.est.2024.114358","url":null,"abstract":"<div><div>Porous carbon nanofibers (PCNFs) offer the advantage of abundant pathways for ion, molecule, and nanoparticle transport, but controlling their porous structure remains a significant challenge. This study employed polytetrafluoroethylene (PTFE) as a pore-forming agent and polyvinylpyrrolidone (PVP) as a carbon precursor to prepare flexible, geometrically adjustable PCNFs with a hierarchical pore structure using a macro-micro dual-phase separation method. The negatively charged PTFE template crosslinks with positively charged PVP carbon precursor, forming stable electrospinning solution. By varying the mass ratio of PVP to PTFE, the pore structure and pore size distribution of PCNFs can be adjusted. 1–2 PCNFs (1PVP/2PTFE) exhibit high capacitance of 397.14 F/g at a current density of 1 A/g due to their higher specific surface area and reasonable pore structure and distribution. Additionally, it has excellent rate capability and cyclic stability at a current density of 10 A/g with a capacitance retention exceeding 100 % and coulombic efficiency remaining above 96.5 % after 5000 cycles. The hierarchical porous structure, N-F-O ternary doping, and high conductivity network proposed in this paper effectively enhance the electrochemical performance of PCNFs films. The method employed in this study can effectively realize high-performance electrode materials, with promising prospects for potential applications in energy storage.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Application of additive-free, ultra-stable polyimide-derived porous carbon with controllable structure in flexible supercapacitors","authors":"","doi":"10.1016/j.est.2024.114359","DOIUrl":"10.1016/j.est.2024.114359","url":null,"abstract":"<div><div>Polymer-derived nitrogen-doped porous carbon networks display stable electrochemical properties and have been extensively studied as electrode materials. However, the precise control of pore morphology and size distribution remains challenging. Herein, the pore structure of polyimide membranes was initially established by controlling the coating thickness. Subsequent to carbonization, the pore morphology and surface area were further controlled. The resulting optimized porous carbon exhibits a uniform pore distribution, a large specific surface area, and appropriate heteroatom content. In a three-electrode system, it achieves a specific capacitance of 328.4 F g<sup>−1</sup> at 0.5 A g<sup>−1</sup>. Additionally, the symmetric supercapacitor delivers an impressive energy density of 20.3 Wh kg<sup>−1</sup> at 350 W kg<sup>−1</sup> in a 6 M KOH electrolyte, retaining 88.5 % of its specific capacity after 5000 cycles. Notably, the specific capacitance of a flexible solid-state device is 151.6 mF cm<sup>−2</sup> at 2 mA cm<sup>−2</sup>. This work introduces a simple, environmentally friendly approach for producing porous carbon from polyimide with adjustable morphology.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Beeswax as a sustainable thermal energy storage material: Experimental thermal assessment in solar air heater","authors":"","doi":"10.1016/j.est.2024.114398","DOIUrl":"10.1016/j.est.2024.114398","url":null,"abstract":"<div><div>The significant disadvantage of paraffin wax as a phase change material (PCM) for thermal energy storage is its petroleum-based nature, which requires large carbon footprint especially in its production. Therefore, to minimize the environmental implications of the large carbon footprint, it is crucial to introduce organic alternatives to it as a thermal energy storage medium. This work aims to assess the potential of beeswax (BW) as an organic, naturally occurring PCM for thermal energy storage in solar air heater (SAH). The experimental results highlight the potential of BW as a thermal energy storage material, where it contributes to store the high amount of heat during the charging heat time and discharge it for approximately 4 h longer than the SAH without BW. Not only that, the application of BW also improves the energy and exergy gains of the SAH at discharge heat times (sunset), which were reflected in the improvement in the energy and exergy efficiencies by 68.46 % and 84.09 % respectively, at 5: 30 PM as an instantaneous comparison point. These results give an impetus to utilize BW as one of the alternatives to petroleum-based PCM as a thermal energy storage medium in different thermal energy applications.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}