IonicsPub Date : 2025-07-25DOI: 10.1007/s11581-025-06544-2
Saba Zomorrodi, Pirooz Marashi, Zahra Sadeghian, Soheila Javadian
{"title":"Synergistic enhancement of Li 2 FeSiO 4 cathode material via Sn (IV) and nitrogen-doped rGO co-doping strategy for lithium-ion batteries","authors":"Saba Zomorrodi, Pirooz Marashi, Zahra Sadeghian, Soheila Javadian","doi":"10.1007/s11581-025-06544-2","DOIUrl":"10.1007/s11581-025-06544-2","url":null,"abstract":"<div><p>To address the intrinsic limitations of Li<sub>2</sub>FeSiO<sub>4</sub> (LFS) cathode materials, including low electronic and ionic conductivity, a synergistic co-doping strategy was employed. This approach combined Sn(IV) substitution at the Si sites with nitrogen-doped reduced graphene oxide (N-rGO) nanosheets to simultaneously improve multiple electrochemical parameters. While single dopants or additives typically only improve a specific aspect of cathode performance, this dual-doping design enabled a comprehensive improvement in both charge transfer and lithium-ion diffusion kinetics. N-rGO was synthesized using a microwave-assisted method, followed by the incorporation of Sn(IV) using a solid-state method. Band gap was evaluated using diffuse reflectance spectroscopy (DRS). Structural, morphological, and chemical properties were characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman analysis, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Electrochemical investigations, including cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), demonstrated significantly reduced charge transfer resistance and improved redox kinetics. The 4Sn-LFS/NG sample (1% Sn and 5 wt% N-rGO) delivered a high initial discharge capacity of 266.9 mAhg<sup>−1</sup>, significantly exceeding the original LFS (143.6 mAhg<sup>−1</sup>). These improvements are due to the synergistic effects of double doping, which reduced the band gap and improved both ionic and electronic pathways. The results demonstrate that the 4Sn-LFS/NG nanocomposite is a promising cathode candidate for next-generation lithium-ion batteries with superior electrochemical performance.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"8971 - 8989"},"PeriodicalIF":2.6,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IonicsPub Date : 2025-07-24DOI: 10.1007/s11581-025-06551-3
Cheng Guixue, Liang Ziyi, Zhang Chao
{"title":"Research on early fault warning for energy storage batteries based on data-driven approaches","authors":"Cheng Guixue, Liang Ziyi, Zhang Chao","doi":"10.1007/s11581-025-06551-3","DOIUrl":"10.1007/s11581-025-06551-3","url":null,"abstract":"<div><p>Energy storage batteries, as the core of energy storage technology, directly affect the overall efficiency and safe operation of new power systems through their performance and stability. In order to enhance the safety and reliability of energy storage batteries, this paper proposes a data-driven early fault warning method for energy storage batteries. Firstly, the self-attention mechanism (SAM) is employed to capture important information from the input sequence and assign different weights to it. Secondly, the DeepAR model is utilized to learn the trend of battery voltage changes, comprehensively capturing the state variations of the battery. Lastly, the local outlier factor (LOF) algorithm is adopted to build a battery fault early warning model, and grid search is employed to optimize the model’s efficiency and accuracy. Verified through actual data from an energy storage power station in Shanghai, the results indicate that the proposed model has an error within 0.16% when predicting voltage. Additionally, it achieves a 24-h early fault warning with an accuracy rate of 99.6%, providing reliable support for the safe and stable operation of energy storage systems.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"9331 - 9340"},"PeriodicalIF":2.6,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IonicsPub Date : 2025-07-24DOI: 10.1007/s11581-025-06564-y
Guohua Wang, Shengchao Su, Guoqing Sun, Jing Sun
{"title":"State of health estimation for lithium-ion batteries based on incremental capacity analysis and Mamba model optimized by improved whale optimization algorithm","authors":"Guohua Wang, Shengchao Su, Guoqing Sun, Jing Sun","doi":"10.1007/s11581-025-06564-y","DOIUrl":"10.1007/s11581-025-06564-y","url":null,"abstract":"<div><p>Accurate estimation of the state of health (SOH) for lithium-ion batteries (LIBs) is paramount for battery management systems (BMS) to ensure safe operation and extend the lifespan of applications such as electric vehicles (EVs). However, existing data-driven methods face inherent limitations regarding feature engineering complexity, long-term estimation accuracy, and hyperparameter optimization, restricting their effective application in practical BMS. To address these limitations, the novel SOH estimation method based on the improved whale optimization algorithm (IWOA)-Mamba with six strongly correlated aging features is proposed. The method employs incremental capacity analysis (ICA) to extract six features strongly correlated with and effectively characterizing battery degradation. Subsequently, the Mamba model is constructed using these features to predict SOH. Furthermore, the IWOA, enhanced with four improvement strategies compared to the standard whale optimization algorithm (WOA), is employed to optimize Mamba’s hyperparameters. This approach overcomes the drawbacks of manual hyperparameter tuning and improves the estimation accuracy of the resulting IWOA-Mamba model. The proposed method is validated using two public battery datasets: NASA and CALCE. Evaluation results demonstrate that the IWOA-Mamba model effectively enhances SOH estimation accuracy, with mean absolute error (MAE) and root mean squared error (RMSE) values predominantly remaining below 0.7%.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"9291 - 9311"},"PeriodicalIF":2.6,"publicationDate":"2025-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Preparation and electrochemical performance of LiF-V2O3 composite cathode for lithium-ion batteries","authors":"Liping Ning, Zhixing Sui, Anping Tang, Ziqin Liang, Hezhang Chen, Haishen Song, Guorong Xu","doi":"10.1007/s11581-025-06542-4","DOIUrl":"10.1007/s11581-025-06542-4","url":null,"abstract":"<div><p>Conversion reactions have made LiF-metal oxide (MO) composites with attractive specific capacities compelling candidates for the next generation of lithium-ion battery cathode materials. However, it is necessary for the high charge voltage (> 4.5 V) to drive the redox reaction of MOs and break a strong ionic bond between Li<sup>+</sup> and F<sup>−</sup> upon charge. It is a crucial way for decrease in the charge voltage to lower the activation energy barrier of the redox process between LiF and MOs. A novel conversion cathode LiF-V<sub>2</sub>O<sub>3</sub> system is proposed in this study. Unlike most of the previously reported LiF-MOs systems, the LiF-V<sub>2</sub>O<sub>3</sub> system can work at the lower charge cut off voltage of 4.3 V. It delivers a reversible specific capacity of 197 mAh g<sup>−1</sup> at C/20 rate in the voltage range of 2–4.3 V. Cyclic voltammetry data suggest a dominant contribution of pseudocapacitance effect in the conversion reaction of the LiF-V<sub>2</sub>O<sub>3</sub> sample.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"8961 - 8969"},"PeriodicalIF":2.6,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IonicsPub Date : 2025-07-23DOI: 10.1007/s11581-025-06549-x
N. Shamimabanu, S. Selvanayagam, S. Selvasekarapandian, S. Kamatchi Devi, S. Aafrin Hazaana, N. Muniraj Vignesh, N. Usha
{"title":"Fabrication and characterization of polymer electrolyte based on PAN with NaSCN for solid-state sodium-ion batteries","authors":"N. Shamimabanu, S. Selvanayagam, S. Selvasekarapandian, S. Kamatchi Devi, S. Aafrin Hazaana, N. Muniraj Vignesh, N. Usha","doi":"10.1007/s11581-025-06549-x","DOIUrl":"10.1007/s11581-025-06549-x","url":null,"abstract":"<div><p>Sodium-ion batteries (SIBs) are considered next-generation energy storage devices due to their abundant availability and cost-effectiveness. SIBs serve as a promising alternative to lithium-ion batteries (LIBs). In this study, an effort is made to develop sodium-ion conducting electrolytes using polyacrylonitrile (PAN) as the host polymer and sodium thiocyanate (NaSCN) by the solution casting technique. The prepared sodium-ion conducting membranes are characterized using X-ray diffraction analysis (XRD) to examine their amorphous/crystalline nature. The complex formation between the salt and polymer is confirmed by Fourier transform infrared spectroscopy (FTIR). The sodium-ion conductivity of the prepared membranes is measured using the AC impedance technique. The solid polymer membrane composed of 55 wt.% PAN/45 wt.% NaSCN exhibits a high sodium-ion conductivity of 8.8 × 10<sup>−3</sup> S/cm. This polymer membrane exhibits a low glass transition temperature (<i>T</i><sub><i>g</i></sub>). Linear sweep voltammetry (LSV) and cyclic voltammetry (CV) studies are performed for high-conducting membrane to evaluate their electrochemical stability. A primary solid-state sodium-ion battery is constructed using the high sodium-ion conducting polymer electrolyte which exhibits an open circuit voltage of 2.52 V. When a load of 100 kΩ is connected across the battery, a current of 21 µA is drawn. The performance of the primary solid-state SIB is evaluated under various loads.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"9085 - 9104"},"PeriodicalIF":2.6,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IonicsPub Date : 2025-07-22DOI: 10.1007/s11581-025-06555-z
Hassan Shirani-Faradonbeh, Ashkan Nahvibayani, Mohsen Babaiee, Rahim Eqra, Mohammad Hadi Moghim
{"title":"Exploring the impact of ({varvec{gamma}})-Al2O3 coating on reaction kinetics and lithium-ion diffusion in LiNi0.5Mn0.3Co0.2O2 cathode materials: a tale of two techniques","authors":"Hassan Shirani-Faradonbeh, Ashkan Nahvibayani, Mohsen Babaiee, Rahim Eqra, Mohammad Hadi Moghim","doi":"10.1007/s11581-025-06555-z","DOIUrl":"10.1007/s11581-025-06555-z","url":null,"abstract":"<div><p>The surface of LiNi<sub>0.5</sub>Mn<sub>0.3</sub>Co<sub>0.2</sub>O<sub>2</sub> (NMC532) cathode material reacts easily with electrolytes in Li-ion batteries, causing capacity fade during cycling. In this research, ultrasonic-assisted and dry-mixed coating techniques are compared as coating methods of γ-Al<sub>2</sub>O<sub>3</sub> nanoparticles on NMC532 to fix this issue. Microscopy techniques reveal the porous layer of Al<sub>2</sub>O<sub>3</sub> with different uniformity. Cyclic voltammograms confirm less lithium-ion loss during the formation process and minimum electrode/electrolyte side reactions for coated samples. The discharge capacity retentions of pristine (PNMC), ultrasonic-assisted (UNMC), and dry-mixed (DNMC) NMC cathodes are 80.3, 91.9, and 78.7% after 100 cycles at 0.5C, and the coated samples experience superior rate performance. Electrochemical impedance spectroscopy evaluations depict that faster Li<sup>+</sup> diffusion with decreased charge transfer resistance and increased interfacial stability are both made possible by the γ-Al<sub>2</sub>O<sub>3</sub> uniform surface coating. Cycling also has a negative effect on diffusion coefficients for both pristine and coated electrodes. Finally, Li-ion diffusion coefficient is calculated from electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic intermittent titration technique, and it shows that the diffusion coefficient of UNMC is higher than that of PNMC and DNMC, which establishes the fact that the ultrasonic-assisted coating layer can enhance lithium-ion diffusion during the extraction/insertion processes more effectively.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"8931 - 8946"},"PeriodicalIF":2.6,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Phase structure, AC conductivity, and thermistor performance in 0.70Na₀.₅Bi₀.₅TiO₃–0.30BaMn₀.₅Ti₀.₅O₃ ceramics","authors":"Pratiksha Agnihotri, Rahul Goel, Priyanka, Radheshyam Rai, Pawan Kumar","doi":"10.1007/s11581-025-06528-2","DOIUrl":"10.1007/s11581-025-06528-2","url":null,"abstract":"<div><p>This study investigates the structural, dielectric, and magnetic properties of a 0.70Na₀.₅Bi₀.₅TiO₃ − 0.30BaMn₀.₅Ti₀.₅O₃ composite synthesized via the solid-state reaction method. X-ray diffraction (XRD) analysis confirms a tetragonal P4-mm crystal structure, with Rietveld refinement providing a good fit. A minor TiO₂ rutile phase is detected. Scanning electron microscopy (SEM) reveals agglomerated, irregular nanoparticles, which influence the dielectric behavior of the material. Dielectric studies show that the permittivity decreases with increasing frequency, in agreement with dipole relaxation behavior described by the Havriliak-Negami model. AC conductivity measurements, following Jonscher’s power law, suggest thermally activated conduction mechanisms. Impedance spectroscopy, represented by a Nyquist plot, exhibits a single semicircle, indicative of bulk properties, with impedance decreasing at higher temperatures. Lattice expansion, inferred from the shift of the (110) XRD peak to lower 2θ angles, suggests Ba<sup>2</sup>⁺ ion substitution. The Williamson-Hall method estimates the crystallite size and strain, and the calculated tolerance factor (<i>t</i> = 1.25) indicates tetragonal distortion. These results demonstrate that the 0.70Na₀.₅Bi₀.₅TiO₃ − 0.30BaMn₀.₅Ti₀.₅O₃ composite possesses favorable structural, dielectric, and magnetic characteristics, positioning it as a potential candidate for electronic applications.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"9061 - 9083"},"PeriodicalIF":2.6,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IonicsPub Date : 2025-07-22DOI: 10.1007/s11581-025-06546-0
Shujahadeen Bakr Aziz, Abubakr Wsu Muhammed, Sleman Yousif Omar, Dlshad Aziz Hamid, Ibrahim Luqman Salih, Peshawa H. Mahmood, Hazhar Hamad Rasul, Karukh Ali Babakr, Ibrahim Nazem Qader, Pshdar Ahmed Ibrahim, Safar Saeed Mohammed, Rebaz Anwar Omer, Ari Ahmed Abdalrahman, Samir Mustafa Hamad, Peyman Aspoukeh, Sarbast Mamnd Hussein
{"title":"Modulation of ion dynamics and electrical dielectric characteristics in MC:NaF polymer electrolytes through glycerol incorporation","authors":"Shujahadeen Bakr Aziz, Abubakr Wsu Muhammed, Sleman Yousif Omar, Dlshad Aziz Hamid, Ibrahim Luqman Salih, Peshawa H. Mahmood, Hazhar Hamad Rasul, Karukh Ali Babakr, Ibrahim Nazem Qader, Pshdar Ahmed Ibrahim, Safar Saeed Mohammed, Rebaz Anwar Omer, Ari Ahmed Abdalrahman, Samir Mustafa Hamad, Peyman Aspoukeh, Sarbast Mamnd Hussein","doi":"10.1007/s11581-025-06546-0","DOIUrl":"10.1007/s11581-025-06546-0","url":null,"abstract":"<div><p>Polymer electrolytes are essential for advanced applications, particularly in the battery industry, due to their high ionic conductivity and improved material properties. This study enhances the ionic conductivity of a methylcellulose (MC) polymer matrix by incorporating glycerol as a plasticizer at varying concentrations (0, 9, 18, 27, and 36 wt.%). Films were prepared using the casting method with 13% sodium fluoride (NaF), resulting in transparent and flexible films. Characterization was performed using X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and electrochemical impedance spectroscopy (EIS). FTIR analysis showed that increasing glycerol concentrations strengthened hydrogen bonding interactions, which facilitated greater ionic dissociation. XRD results revealed a reduction in bell-shaped peaks, indicating increased segmental freedom of the polymer chains. This structural change created better pathways for cation and anion migration. EIS analysis confirmed a significant improvement in ionic conductivity with glycerol addition. The sample containing 36 wt.% glycerol exhibited the highest conductivity. This enhancement resulted from increased ion dissociation, greater segmental motion of the polymer chains, and reduced polymer rigidity due to glycerol’s plasticizing effect. Dielectric studies further supported these findings. Higher dielectric constants and reduced dielectric loss indicated stronger ionic polarization and enhanced transport mechanisms. These results demonstrate the potential of glycerol-incorporated polymer electrolytes for energy storage applications, contributing to the development of efficient and reliable battery technologies.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"9105 - 9117"},"PeriodicalIF":2.6,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145236816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IonicsPub Date : 2025-07-19DOI: 10.1007/s11581-025-06540-6
Zhuo Zhang, Haotian Shi, Wen Cao, Ke Li, Lei Chen
{"title":"Enhanced bi-directional temporal convolutional gated recurrent hybrid neural network for state of charge estimation of power lithium-ion batteries","authors":"Zhuo Zhang, Haotian Shi, Wen Cao, Ke Li, Lei Chen","doi":"10.1007/s11581-025-06540-6","DOIUrl":"10.1007/s11581-025-06540-6","url":null,"abstract":"<div><p>With the rapid development of applications such as renewable energy and electric vehicles, accurate estimation of the state of charge (SOC) of lithium-ion batteries has become a key technology for improving system safety, prolonging battery life, and optimizing energy management. In order to cope with the complexity caused by the lack of battery modeling accuracy and varying environmental conditions, this paper proposes a data-driven hybrid neural network-based model. Specifically, a bidirectional time convolution network (BiTCN) is used to extract long-term features such as current and voltage. Then, a bidirectional gated recurrent unit (BiGRU) is used to predict the state of charge (SOC) of electric vehicle lithium-ion batteries. In order to obtain the globally optimal hyperparameter settings, a natural heuristic optimization algorithm crown porcupine optimizer (CPO) is introduced. The effectiveness of the fusion method was verified under different working conditions and temperatures. The average MAE for the DST condition is 0.54%, the average RMSE is 0.71%, and the average <i>R</i><sup>2</sup> is 99.91%. The average MAE, RMSE, and <i>R</i><sup>2</sup> for the BBDST condition are 0.72%, 0.92%, and 99.86%, respectively. The prediction performance is significantly improved compared with traditional machine learning methods, which is important for online charge state estimation and health management of electric vehicles.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"9313 - 9329"},"PeriodicalIF":2.6,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145237021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
IonicsPub Date : 2025-07-19DOI: 10.1007/s11581-025-06534-4
Poonam Siwatch, Kriti Sharma, Nirmal Manyani, Yamini Gupta, S. K. Tripathi
{"title":"Optimization of nickel cobalt sulphide nanostructures for supercapacitors application","authors":"Poonam Siwatch, Kriti Sharma, Nirmal Manyani, Yamini Gupta, S. K. Tripathi","doi":"10.1007/s11581-025-06534-4","DOIUrl":"10.1007/s11581-025-06534-4","url":null,"abstract":"<div><p>In this study, nickel cobalt sulphide nanostructures have been synthesized by the hydrothermal synthesis technique at different reaction times of 8 h, 12 h, and 14 h and are named as NCS-I, NCS-II, and NCS-III, respectively. All the nanostructures have been characterized structurally, morphologically, optically and electrochemically, and the best electrochemical behaviour has been exhibited by the NCS-II nanostructure. The crystallite size for the NCS-II sample comes out to be 45.21 nm from X-ray Diffraction, and the specific surface area and pore diameter are calculated to be 35.8 m<sup>2</sup>/g and 2–16 nm, respectively. The flower-like morphology is exhibited by the NCS-II nanocomposite. As synthesized NCS-I, NCS-II, and NCS-III nanostructures exhibit 2.80 eV, 3.15 eV, and 2.84 eV band gaps, respectively. The supercapacitive behaviour of nickel cobalt sulphide nanocomposites has been studied by cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy measurements using FTO Glass and nickel foam as the substrates for electrodes. It has been observed that better electrochemical behaviour is exhibited by NCS structures deposited on Nickel foam substrate due to better conductivity, less electrical resistance, and porous three-dimensional structure of nickel foam. The highest value of energy density has been obtained for the NCS-II nanostructure on Nickel foam (41.1 Wh kg<sup>−1</sup> at current densities of 2.6 A g<sup>−1</sup>) owing to its flower-like morphology. The NCS-II nanocomposite on Nickel foam has retained 74% capacitance after 4000 cycles with a coulombic efficiency of 87.21%, making it an appropriate candidate for flexible supercapacitors.</p></div>","PeriodicalId":599,"journal":{"name":"Ionics","volume":"31 9","pages":"9593 - 9615"},"PeriodicalIF":2.6,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145237087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}