IET Nanodielectrics最新文献

{"title":"Enhancing Electrospun PVDF-HFP Nanofibres for Lithium-Ion Battery Separators Through the Incorporation of Inorganic Nanoparticles: Physico-Chemical and Electrical Characterisation","authors":"Leonardo Gasperini,&nbsp;Iacopo Iannarelli,&nbsp;Simone Vincenzo Suraci,&nbsp;Davide Fabiani","doi":"10.1049/nde2.70021","DOIUrl":"https://doi.org/10.1049/nde2.70021","url":null,"abstract":"<p>This study investigates the physical-chemical and electrochemical performances of innovative separators for Li-ion batteries based on poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) nanofibrous membranes. The nanofibrous mat is produced through the electrospinning process, ensuring high surface to volume (S/V) ratio and allows large-scale production under suitable conditions. The materials investigated in this work aim at overcoming some limitations specific to the commercial separators, for example, mechanical shrinkage and electrolyte uptake. This is achieved by adding nanoparticles of different types, for example, ZrO₂, SnO₂, SiO₂ at different concentrations. Results claim that nanofibrous separators improve the mechanical and thermal stability of the mat without significantly impacting its electrochemical performances. In particular, the addition of 7 wt% of ZrO₂ nanoparticles to the nanofibrous separator showed to outperform commercially available solutions (i.e., Celgard) in terms of mechanical and thermal stability exhibiting, also, electrochemical performances.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70021","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145224543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Generation of High-Efficiency Ziegler–Natta Catalyst for Synthesising Ultra-Clean Isotactic Polypropylene as Capacitor Film Substrate","authors":"Jingjiao Liu,&nbsp;Chaojie Gai,&nbsp;Chao Yu,&nbsp;Kefeng Wang,&nbsp;Chunpeng Cao,&nbsp;Haojie Cao,&nbsp;Jicheng Yu,&nbsp;Jiayong Li,&nbsp;Hongda Jia,&nbsp;Jiali Zheng,&nbsp;Kejing Gao,&nbsp;Qigu Huang","doi":"10.1049/nde2.70018","DOIUrl":"10.1049/nde2.70018","url":null,"abstract":"<p>A series of innovative electron donors (D1–D6) featured both internal and external electron donors in one molecular structure were designed and synthesised. The synthesised electron donors and traditional electron donors (DIBP) were effectively reacted with titanium-based catalysts supported on magnesium chloride to obtain a series of Ziegler–Natta catalysts (Cat 0–Cat 6). Cat 0 formed by electron donor DIBP. Similarly, Cat 1 by D1, Cat 2 by D2, Cat 3 by D3, Cat 4 by D4, Cat 5 by D5 and Cat 6 by D6, respectively, which were characterised by GC-MS, ¹H (¹³C)-NMR, XPS and SEM. It is interesting that the catalytic activity of the catalysts prepared by the newly synthesised electron donor was significantly higher than that of traditional DIBP for propylene polymerisation. Under atmospheric pressure condition of propylene, the catalytic activity of Cat 3 was 112.7 g PP/(g Cat · h) and Cat 6 reached 209.2 g PP/(g Cat · h) at the same conditions, both significantly higher than that of 34.1 g PP/(g Cat · h) of Cat 0. We adopted a prealkylation strategy for the catalysts preparation, reducing the optimal aluminium titanium ratio for propylene polymerisation from 50 to 30, decreasing the amount of cocatalyst used and thus reducing the ash content in the products. During the bulk polymerisation of propylene, the activity of prealkylated Cat 3 and Cat 6 is comparable, at 79.4 kg PP/(g Cat · h), which is about 2.3 times that of Cat 0 cooperated with external electron donor C during the polymerisation processes (35.2 kg PP/(g Cat · h)), and the obtained PP isotacticity reaches over 98%. Especially, Cat 1–Cat 6 were required no external electron donor for propylene polymerisation. In addition, the theoretical ash content of the products formed by Cat 3 and Cat 6 is only 22 ppm, which is significantly lower than that of Cat 0 (133 ppm). It is expected to be used in the industrial production of ultra-clean iPP powder for capacitor films.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70018","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Modification Effects in Metallisation of Dielectric Films","authors":"Jian-Tao Wang,&nbsp;Lei Huang,&nbsp;Shao-Long Zhong,&nbsp;Xin-Jie Wang,&nbsp;Baoquan Wan,&nbsp;Yan-Hui Song,&nbsp;Zhi-Min Dang","doi":"10.1049/nde2.70015","DOIUrl":"10.1049/nde2.70015","url":null,"abstract":"<p>Metallised film capacitors consist of polymer dielectrics and electrodes which are considered as two layers. Due to the huge difference in thickness of two layers, metallisation can affect the microstructure and properties of metallised films, resulting in the bilayer structure model may not accurately describing properties. In this work, metallised films are considered as a whole rather than two layers of dielectric and electrode, whereas the process of film metallisation is regarded as a surface modification of the dielectric film. Metallised films with different metal layer thicknesses are prepared by vacuum evaporation. We investigated the dielectric, electrical and self-healing properties of metallised films. Films with thicker electrode present higher dielectric constant, conductivity, energy density and lower breakdown strength. Thinner metal layers result in less self-healing energy and better self-healing property. The difference in properties is attributed to the surface modification of dielectric films by nanoscale metallisation. Thicker electrode contributes to smaller surface roughness, which increases the polarization and charge capacity of metallised films, but also implies worse self-healing property. Surface modification provides a new perspective for researching metallised films.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70015","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145102057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation Study on Sensitivity Verification of Transformer Partial Discharge Ultrasonic Sensor Affected by Field Noise","authors":"Xiu Zhou,&nbsp;Tian Tian,&nbsp;Longcheng Dai,&nbsp;Jin Bai,&nbsp;Yukun Ma,&nbsp;Yabo Liang,&nbsp;Yifan Chen,&nbsp;Keyun Li","doi":"10.1049/nde2.70012","DOIUrl":"10.1049/nde2.70012","url":null,"abstract":"<p>As a critical component in transformer partial discharge monitoring and localisation, the output signal of the contact ultrasonic sensor is significantly influenced by its sensitivity. Consequently, field sensitivity verification of ultrasonic sensors is essential. However, field calibration is often impacted by environmental noise, and the effects of various noise types on the sensitivity calibration results remain inadequately understood. To address this issue, this paper introduces a sensitivity field calibration process tailored for ultrasonic sensors used in oil-immersed transformer. Transformer and ultrasonic sensor models are developed, and the sensor output signal is simulated using the finite element method. Noise signals of different types are superimposed to evaluate their effects on the sensitivity calibration results. The results indicate that under the interference of narrowband noise, white noise, and mixed noise, significant errors occur in both the root mean square fluctuation of the sensitivity curve and the peak sensitivity, whereas the error in mean sensitivity is comparatively smaller than that of the aforementioned indicators. These results provide a theoretical foundation for the development of targeted denoising techniques during field verification.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70012","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144897524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Dynamics Simulation of the Decomposition and Gas Generation Characteristics of Natural Ester Insulating Oils Under Overheated Conditions","authors":"Yiming Huang,&nbsp;Wu Lu,&nbsp;Weiwei Qi,&nbsp;Jun Zhang","doi":"10.1049/nde2.70016","DOIUrl":"10.1049/nde2.70016","url":null,"abstract":"<p>Natural ester insulating oils are increasingly replacing mineral oils as the insulating medium for oil-filled equipment due to their high ignition point, biodegradability, and other environmentally friendly properties. However, the reaction characteristics of natural ester insulating oils under different types of faults require further investigation. This paper presents the development of a molecular dynamics model employing the ReaxFF reactive force field to comprehensively simulate the decomposition of natural ester insulating oils over a temperature range of 2800–4000 K, elucidating the resulting product information. The gas production behaviour of natural ester insulating oils was examined under different overheating conditions and heating times. The simulation results indicate that the thermal decomposition products of natural ester insulating oil primarily consist of seven gases, including H₂, CO, CO₂, and others. Notably, the concentration of C₂H₄ gas exhibits a significantly nonlinear negative correlation with overheating conditions. Because of variations in simulation temperatures, the characteristic gases generated during the thermal decomposition of natural ester insulating oil correspond to different fault types observed in real-world scenarios. Specifically, the gas production at a simulated temperature of 4000 K aligns with the gas production behaviour of insulating oil during discharge fault events in practice. The results of this study offer a theoretical basis for the application of insulation condition monitoring in oil-filled equipment through dissolved gas analysis (DGA).</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70016","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145128859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical, Dielectric and Hydrophobic Properties of Phenyl Silicone Rubber and Methyl Vinyl Silicone Rubber Blend Composites","authors":"Xiaoli Liu,&nbsp;Hui Ao,&nbsp;Yankai Lin,&nbsp;Jian Wang,&nbsp;Shaojian He","doi":"10.1049/nde2.70014","DOIUrl":"10.1049/nde2.70014","url":null,"abstract":"<p>Silicone rubber (SIR) composite insulators are widely employed in electrical applications due to their exceptional chemical stability, low surface energy and superior electrical insulation properties. To enhance the hydrophobicity and low-temperature resistance of SIR, blended composites with varying ratios of SIR and phenyl silicone rubber (PSIR) were fabricated. The study revealed that matrix-filler network interactions between PSIR and fillers were weaker compared to those in SIR-based systems. Increasing PSIR content led to reduced elongation at break in the composites, while tensile strength remained largely unchanged. Concurrently, the breakdown strength is inferior to that of pure PSIR composites. Notably, the blend of SIR and PSIR enhances both hydrophobicity and resistance to hydrophobicity migration. This work provides a strategic approach for enhancing the performance of SIR composites suitable for applications in regions with high humidity and significant rainfall.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70014","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144657603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temperature Dependence of the Polarisation Characteristics of Epoxy Resin for Electrical Insulation","authors":"Qian Wang,&nbsp;Ting Lei,&nbsp;Jingyu Deng,&nbsp;Xidong Liang,&nbsp;Chao Wu","doi":"10.1049/nde2.70013","DOIUrl":"10.1049/nde2.70013","url":null,"abstract":"<p>Epoxy resin-based dielectric materials are widely used for electrical insulation. However, due to the application of electrical equipment in complex and diverse climatic environments, the characteristic variation of the material must be paid attention to. Besides, decoupling of the overall performance is necessary to trace the source of property variation. Thus, in this research, the polarisation characteristics over broad ranges of temperature and frequency of typical epoxy resin used for electrical insulation are investigated. Moreover, the Dissado–Hill model is adopted to quantitatively decouple the individual contribution of each microprocess. It indicates that the magnitudes of the polarisation processes below the glass transition temperature (<i>T</i>_g) are small, the influence of which on the overall polarisation characteristics is marginal. In comparison, the influence of <i>α</i> relaxation initiating above <i>T</i>_g on the magnitude of permittivity and the dielectric loss is prominent, which must be fully taken into consideration during insulation design. In addition, due to the long structure of repeating units in the backbone of epoxy, another polarisation process would appear at higher temperatures stemming from the internal relaxation of repeating units. Furthermore, the amplitude of conductance increases exponentially as temperature rises and would become the major component of loss at elevated temperatures. This research provides insights into the rational design of insulation structures and the development of novel epoxy materials.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144624590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Flashover Phenomena and Contributory Parameters in Oil-Pressboard Composite Insulation System Under DC Voltage","authors":"Kai Zhou,&nbsp;Bo Jiang,&nbsp;Zilu Wang,&nbsp;Li Chen,&nbsp;Yu Shen,&nbsp;Zihan Teng,&nbsp;Lei Jin,&nbsp;Meng Huang","doi":"10.1049/nde2.70011","DOIUrl":"10.1049/nde2.70011","url":null,"abstract":"<p>During the operation of HVDC transmission systems, the oil-pressboard insulation of converter transformers is constantly subjected to combined AC and DC voltages. The DC voltage component can easily lead to charge accumulation and induce surface flashover. To investigate the development process of surface flashover in oil–pressboard insulation under DC voltage and its influencing factors, this paper establishes a two-dimensional simulation model using finite element simulation software to study the electric field and charge distribution characteristics of oil–pressboard composite insulation systems. Using the established model, the paper analyses the influence of voltage, gap distance and electron mobility on the surface flashover development process.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Oxygen on the Insulation Characteristics of Eco-Friendly Insulating Gas HFO-1336mzz(E)/CO2","authors":"Song Xiao,&nbsp;Mingjun Tang,&nbsp;Chengying Wu,&nbsp;Hongsong Lian,&nbsp;Fei Wang,&nbsp;Haoran Xia,&nbsp;Ju Tang,&nbsp;Yi Li","doi":"10.1049/nde2.70010","DOIUrl":"10.1049/nde2.70010","url":null,"abstract":"<p>HFO-1336mzz(E)/CO₂, an eco-friendly insulating gas, garnered considerable interest recently as a potential substitute for SF₆ in gas-insulated equipment. To reduce the precipitation of fluorocarbon gases and solids during the decomposition process of HFO-1336mzz(E)/CO₂ gas mixture, O₂ is normally introduced as an additive. Herein, we investigated the influence of oxygen on the insulation performance of HFO-1336mzz(E)/CO₂ under different electric field non-uniformities by evaluating the breakdown voltage, PDIV, PDEV and decomposition characteristics. The findings indicate that in a quasi-uniform electric field, the breakdown voltage of the gas mixture progressively increases with the oxygen volume fraction. Under the extremely non-uniform electric field, both the breakdown voltage and PDIV initially rise and subsequently decline with the increase of oxygen volume fraction, reaching a peak at 6%. The PD decomposition analysis reveals that the addition of 4% oxygen can reduce the decomposition of HFO-1336mzz(E), which is most beneficial to improve the comprehensive insulation performance of the gas mixture.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144256359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced High-Temperature Energy Storage Properties of BOPP Capacitor Films by Coating Heterostructural Ceramics Layers","authors":"Zhaoliang Xing,&nbsp;Bize Gong,&nbsp;Tianyuan Yin,&nbsp;Shaowei Guo,&nbsp;Bo Yang,&nbsp;Tiandong Zhang,&nbsp;Jianhong Hao","doi":"10.1049/nde2.70009","DOIUrl":"10.1049/nde2.70009","url":null,"abstract":"<p>Biaxially oriented polypropylene (BOPP), the dielectric material of choice for polymer film capacitors, is widely used in advanced electronic devices and power grids, among other applications. However, the nonlinear growth of the conduction loss at high temperatures leads to a rapid deterioration of its energy storage performance, which seriously hinders the development trend of miniaturisation and high integration of power systems. In this study, inorganic nanolayers with heterogeneous structure were grown on the surface of BOPP films by magnetron sputtering using high dielectric constant BaZrTiO₃ and wide bandgap Al₂O₃ ceramic targets. Experimental and theoretical analyses show that the use of wide bandgap Al₂O₃ as the heterojunction outer layer can effectively impede carrier injection and transport, leading to a significant reduction in the leakage current density of the composite film, effectively enhancing the high temperature energy storage performance of the composite films. The synergistic enhancement of the inorganic heterojunction structure on the dielectric properties and insulating strength of the polymer film is attributed to the ability of the Al₂O₃/BaZrTiO₃/BOPP/BaZrTiO₃/Al₂O₃ (O-B-P-B-O) composite films to exhibit a discharge energy density of 2.49 J/cm³ and a charge/discharge efficiency of 77.6% at 125°C and 500 MV/m.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":"8 1","pages":""},"PeriodicalIF":3.8,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.70009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144108962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}