Journal of Power Sources最新文献_第3页

Self-seeded growth of hexagonal-phase WO3 film by a one-step hydrothermal method for high-performance electrochromic energy storage devices

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-11 DOI: 10.1016/j.jpowsour.2025.236350

Yi Wang , Zilong Zhang , Ze Wang , Yan Zuo , Haichuan Zhou , Dongya Sun , Yuechan Li , Yujie Yan , Tong Feng , An Xie

{"title":"Self-seeded growth of hexagonal-phase WO3 film by a one-step hydrothermal method for high-performance electrochromic energy storage devices","authors":"Yi Wang , Zilong Zhang , Ze Wang , Yan Zuo , Haichuan Zhou , Dongya Sun , Yuechan Li , Yujie Yan , Tong Feng , An Xie","doi":"10.1016/j.jpowsour.2025.236350","DOIUrl":"10.1016/j.jpowsour.2025.236350","url":null,"abstract":"<div><div>Electrochromic devices have garnered significant interest due to their great potential in intelligent multifunctional electrochromic energy storage devices (EESDs) and smart electronics. Tungsten oxide (WO₃) exhibits both electrochromic and pseudocapacitive characteristics, and combining these two functionalities into a single device with enhanced overall performance is a popular research topic. However, synthesizing high-performance WO₃ electrochromic films with an efficient and simple method remains a challenge. Herein, a one-step fabrication strategy is developed for the in-situ growth of hexagonal WO₃ films on FTO substrates. This strategy employs a low-temperature hydrothermal method, involving xylitol as a self-seeding agent and cesium sulfate as a capping agent. The synergistic effect of the self-seeding and capping agents results in highly efficient WO₃ films with strong substrate adhesion and a large optical modulation (86.8 %). An EESD is assembled using the WO₃ film as the working electrode and a PB film as the counter electrode. The EESD demonstrates fast bleaching/coloration switching times and a high coloration efficiency of 104.8 cm<sup>2</sup> C⁻<sup>1</sup>. Additionally, the EESD shows a distinct and reversible color transition from transparent to dark blue, accompanied by a change in optical transmittance of 74.45 %.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236350"},"PeriodicalIF":8.1,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387923","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}

引用次数: 0

Novel high-entropy oxides with ultra-long cycle life as cathode materials for aqueous zinc-ion batteries

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-11 DOI: 10.1016/j.jpowsour.2025.236488

Zhixian Wu , Qidong Lv , Wei Sun , Heng Zhang , Youcun Bai , Chang Ming Li

{"title":"Novel high-entropy oxides with ultra-long cycle life as cathode materials for aqueous zinc-ion batteries","authors":"Zhixian Wu , Qidong Lv , Wei Sun , Heng Zhang , Youcun Bai , Chang Ming Li","doi":"10.1016/j.jpowsour.2025.236488","DOIUrl":"10.1016/j.jpowsour.2025.236488","url":null,"abstract":"<div><div>Aqueous zinc-ion battery (AZIB), as a promising economic and environmentally friendly battery, has been plagued by the instability and structural collapse of cathode materials during charge-discharge process for many years, which has seriously hindered its commercial application. At present, researchers have used intercalation, surface coating and other means to inhibit the dissolution of cathode materials, but they have not achieved satisfactory results. In order to fundamentally improve the stability of AZIB cathode, we prepared a high-entropy oxide cathode material (Co<sub>0.2</sub>Cr<sub>0.2</sub>Fe<sub>0.2</sub>Mn<sub>0.2</sub>Ni<sub>0.2</sub>)<sub>3</sub>O<sub>4</sub> (CCFMnO) derived from the concept of high entropy. Because of the unique entropy stabilization effect and strong lattice distortion effect of high-entropy materials, CCFMnO shows satisfactory structural stability. Compared with the low-entropy material Fe<sub>3</sub>O<sub>4</sub>, the CCFMnO nanomaterial achieved enhanced electrochemical performance due to the synergistic effect of multiple elements, exhibiting an excellent specific capacity (283 mAh g<sup>−1</sup> at 0.1 A g<sup>−1</sup>), good rate capability, and superior cycle stability (66.61 % capacity retention after 90000 cycles at 2 A g<sup>−1</sup>). In addition, we reveal the storage mechanism and structural evolution of Zn<sup>2+</sup> during the intercalation/deintercalation of CCFMnO by a series of in-situ and ex-situ characterization methods. This work opens the way to explore new AZIB cathode materials, which will promote the development of AZIB.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"634 ","pages":"Article 236488"},"PeriodicalIF":8.1,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387263","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}

引用次数: 0

A hybrid method combining degradation mechanisms and deep learning for lifetime prediction of proton exchange membrane fuel cells under dynamic load cycle conditions

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-10 DOI: 10.1016/j.jpowsour.2025.236464

Chang Ke , Kai Han , Yongzhen Wang

{"title":"A hybrid method combining degradation mechanisms and deep learning for lifetime prediction of proton exchange membrane fuel cells under dynamic load cycle conditions","authors":"Chang Ke , Kai Han , Yongzhen Wang","doi":"10.1016/j.jpowsour.2025.236464","DOIUrl":"10.1016/j.jpowsour.2025.236464","url":null,"abstract":"<div><div>Prognostics and health management (PHM) is an effective method to improve the durability of proton exchange membrane fuel cells (PEMFCs). Accurate lifetime prediction is an essential prerequisite for health management. This paper proposes a hybrid prediction method that combines degradation mechanisms with deep learning neural networks to predict the degradation trends and estimate the remaining useful life (RUL) of PEMFCs under dynamic load cycle conditions. Firstly, the polarization curve model is employed to extract degradation-related parameters and quantify the overvoltage. The relationship between overvoltage and membrane electrode assembly (MEA) degradation is analyzed, revealing that cathode catalyst and membrane are the key components influencing the degradation. Secondly, a comprehensive degradation index (CDI) is developed. A novel method for quantifying the weight coefficients of the CDI is proposed for the first time. The effects of catalyst and membrane degradation on the overall performance degradation are quantified, which are 82.2 % and 17.8 %, respectively. Finally, the long short-term memory (LSTM) and gated recurrent unit (GRU) models are employed to predict the degradation trend. The results show that GRU outperforms LSTM in this study. The maximum RUL estimation error of the proposed hybrid method is 9.50 %, with all errors within the 10 % confidence interval.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236464"},"PeriodicalIF":8.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377141","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}

引用次数: 0

High-performance crystalline nanocellulose (CNC) supercapacitor separator: Achieved by maximizing alkali-induced gel stress-response prior to aerogel compression forming

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-10 DOI: 10.1016/j.jpowsour.2025.236476

Daniel M. Mijailović , Patrick A.C. Gane , Katarina Dimić-Mišić , Monireh Imani , Dušica B. Stojanović , Petar S. Uskoković

{"title":"High-performance crystalline nanocellulose (CNC) supercapacitor separator: Achieved by maximizing alkali-induced gel stress-response prior to aerogel compression forming","authors":"Daniel M. Mijailović , Patrick A.C. Gane , Katarina Dimić-Mišić , Monireh Imani , Dušica B. Stojanović , Petar S. Uskoković","doi":"10.1016/j.jpowsour.2025.236476","DOIUrl":"10.1016/j.jpowsour.2025.236476","url":null,"abstract":"<div><div>This study presents the design and fabrication of high-performance separators for supercapacitors based on a novel finding relating to the structural response between alkali ions and cellulose nanocrystals (CNC). Unlike prior art, the CNC-to-ion ratio was specifically chosen following an observed bimodal rheological stress response to applied strain. The stress maximum passed at higher ion concentration was taken to indicate an optimally permeable cellulose cage-structure development, verified by microscopic imaging of the resultant freeze-dried aerogel. The compressed dried structure demonstrates excellent overall performance, including high average nano hardness (∼122 MPa) and ionic conductivity (∼103.5 mS cm<sup>−1</sup>) after rewetting at 80 w/w% solids content, outperforming commercial borosilicate glass microfiber separator. Benefiting from its hydrophilicity and high porosity, the rehydrated separator demonstrated efficient potassium ion transport. Integrated into symmetric supercapacitor devices with glucose-derived mesoporous carbon electrodes (∼850 m<sup>2</sup> g<sup>−1</sup>), the device delivers high specific capacitance (∼80 F g<sup>−1</sup> at 10 mV s<sup>−1</sup>), high energy density (2.7 Wh kg<sup>−1</sup> at 98.2 W kg<sup>−1</sup>), and approximately 95 % capacitance retention after 1000 cycles. These findings suggest that prior rheological identification of optimal structuration during ion addition to CNC in aqueous suspension greatly enhances the suitability of these innovative materials for renewable energy storage applications.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236476"},"PeriodicalIF":8.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143379134","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}

引用次数: 0

Ultrasonic estimation of lithium-ion battery state parameters using hybrid sparrow search algorithm and relevance vector machine

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-10 DOI: 10.1016/j.jpowsour.2025.236469

Zhang Binpeng , Zheng Yang , Gao Jie , Lyu Yan , Cao Liangcai , He Cunfu

{"title":"Ultrasonic estimation of lithium-ion battery state parameters using hybrid sparrow search algorithm and relevance vector machine","authors":"Zhang Binpeng , Zheng Yang , Gao Jie , Lyu Yan , Cao Liangcai , He Cunfu","doi":"10.1016/j.jpowsour.2025.236469","DOIUrl":"10.1016/j.jpowsour.2025.236469","url":null,"abstract":"<div><div>State of Charge and State of Health are critical indicators for evaluating the operational status of lithium-ion batteries. Accurate estimation of these parameters is essential for ensuring safe operation and optimizing charging-discharging performance. This study presents a novel method for estimating SOC and SOH based on ultrasonic characteristics. A pouch battery is selected as the experimental object, with ultrasonic waves extracted in real-time during battery operation. Acoustic parameters are obtained via signal processing to establish a training dataset for SOC estimation. Additionally, the impact of varying discharge rates on battery capacity degradation is analyzed to support battery aging experiments. During the aging experiments, real-time acoustic parameters are collected to develop a training dataset for SOH estimation. The results indicate a strong correlation between the acoustic parameters and the SOH. Moreover, the acoustic parameters serve as the characteristic parameters, and a hybrid-model combining the sparrow search algorithm and relevance vector machine is employed to accurately estimate the state parameters. The maximum relative error for the SOC estimation is 1.51 %, while the maximum absolute error for the SOH estimation is 0.79 %. The research results provide a new technical support for the non-destructive quantitative characterization of lithium-ion battery state parameters.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236469"},"PeriodicalIF":8.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377142","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}

引用次数: 0

Boosting hydrogen peroxide electro-generation by adjusting the wetting state of porous Janus electrode during oxygen reduction reaction

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-10 DOI: 10.1016/j.jpowsour.2025.236454

Yijing Xia , Jingsong Dai , Yifei Peng , Yuqi Guan , Yangcheng Ding , Huajun Feng

{"title":"Boosting hydrogen peroxide electro-generation by adjusting the wetting state of porous Janus electrode during oxygen reduction reaction","authors":"Yijing Xia , Jingsong Dai , Yifei Peng , Yuqi Guan , Yangcheng Ding , Huajun Feng","doi":"10.1016/j.jpowsour.2025.236454","DOIUrl":"10.1016/j.jpowsour.2025.236454","url":null,"abstract":"<div><div>This study aims to design a porous Janus polyacrylonitrile-based carbon fiber (PCF) electrode with asymmetric interfacial wettability for the simultaneous management on oxygen diffusion and ion transfer for H<sub>2</sub>O<sub>2</sub> electro-generation. The wetting state of PCF electrode is adjusted by the facile deposition of polytetrafluoroethylene (PTFE) via capillarity. In contrast to single aerophobic and aerophilic electrodes, the Janus PCF electrodes provide a stable gas film for promoting oxygen transfer while ensuring rapid ion migration and release. Compared to the other Janus electrodes, the porous PCF electrode subjected to three cycles of PTFE modification (named Janus-3) exhibit richer functional groups that improves two-electron oxygen reduction reaction (2e<sup>−</sup>-ORR) performance with reduced onset potential and higher current increase rate. And the excellent characteristics of Janus-3 contribute to the highest H<sub>2</sub>O<sub>2</sub> production rate of 10.61 ± 0.13 mg h<sup>−1</sup> cm<sup>−2</sup> in a flow-through electrochemical system, along with the highest current efficiency (CE) and oxygen utilization efficiency (OUE) values of 83.63 ± 1.01 % and 81.22 ± 4.13 %, respectively. The oxygen mass transfer and ion transport mechanism of H<sub>2</sub>O<sub>2</sub> electro-generation are revealed. Lastly, long-lasting operation stability of Janus-3 and its high H<sub>2</sub>O<sub>2</sub> production, CE, and OUE suggest great potential to replace normal gas diffusion electrodes for H<sub>2</sub>O<sub>2</sub> electro-generation.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236454"},"PeriodicalIF":8.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377154","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}

引用次数: 0

Constructing Fe₂O₃/Carbon heterointerfaces on porous carbon fibers: Achieving a synergistic effect for enhanced supercapacitors

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-10 DOI: 10.1016/j.jpowsour.2025.236468

Zhongtao Shang , Tao Zhang , Qiao Yang , Dingke Wang , Yuyi Liao , Dongjia Xie , Yiyang Dai , Yuan Wang , Shaojun Yuan

{"title":"Constructing Fe₂O₃/Carbon heterointerfaces on porous carbon fibers: Achieving a synergistic effect for enhanced supercapacitors","authors":"Zhongtao Shang , Tao Zhang , Qiao Yang , Dingke Wang , Yuyi Liao , Dongjia Xie , Yiyang Dai , Yuan Wang , Shaojun Yuan","doi":"10.1016/j.jpowsour.2025.236468","DOIUrl":"10.1016/j.jpowsour.2025.236468","url":null,"abstract":"<div><div>Nanocomposites consisting of metal oxide and carbon materials are usually preferred as electrode for electrochemical energy storage. Nonetheless, their unsatisfied capacitance hinders the reached energy density of aqueous supercapacitors (SCs). Herein, Fe<sub>2</sub>O<sub>3</sub>/carbon heterointerface was constructed on porous carbon fiber (PCF), which could serve as an efficient active site for stabilizing K<sup>+</sup> and Na<sup>+</sup> storage. The theoretical calculations revealed the enhanced accumulation and transfer of charges around the Fe<sub>2</sub>O<sub>3</sub>/carbon interface, thus favoring the electron transfer and boosting the faradaic reaction. The interactions of Fe<sub>2</sub>O<sub>3</sub> and PCF was found to simultaneously cause faster ion transfer and more surface charge storage, which made the as-prepared Fe<sub>2</sub>O<sub>3</sub>@PCF electrode deliver a superior SCs performance in 2 M KCl or 1 M Na<sub>2</sub>SO<sub>4</sub> electrolyte. The asymmetric aqueous supercapacitor devices consisted of Fe<sub>2</sub>O<sub>3</sub>@PCF and MnO<sub>2</sub>/CC electrodes with maximum operating potential of 2.0 V achieved a high areal energy density of 0.126 mWh cm<sup>−2</sup> at a power density of 1.2 mW cm<sup>−2</sup> along with good stability.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236468"},"PeriodicalIF":8.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143379133","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}

引用次数: 0

Engineering high-concentration electrolyte with high ionic conductivity and solvation structure regulation enables high-performance Li/CFx primary batteries

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-10 DOI: 10.1016/j.jpowsour.2025.236440

Gaoyu Zhou , Jiangmin Jiang , Qilin Feng , Fei Zhou , Xia Qiu , Yaxin Chen , Xiangkai Kong , Zhicheng Ju , Yanhua Cui , Quanchao Zhuang

{"title":"Engineering high-concentration electrolyte with high ionic conductivity and solvation structure regulation enables high-performance Li/CFx primary batteries","authors":"Gaoyu Zhou , Jiangmin Jiang , Qilin Feng , Fei Zhou , Xia Qiu , Yaxin Chen , Xiangkai Kong , Zhicheng Ju , Yanhua Cui , Quanchao Zhuang","doi":"10.1016/j.jpowsour.2025.236440","DOIUrl":"10.1016/j.jpowsour.2025.236440","url":null,"abstract":"<div><div>Lithium/fluorinated carbon (Li/CF<sub>x</sub>) batteries have garnered significant interest because of their exceptionally high theoretical energy density compared to other primary energy storage systems. However, the slow ionic transport of the electrolyte during the discharge phase restricts its ability to achieve the theoretical maximum. Herein, a novel high-concentration electrolyte is proposed based on one salt (lithium tetrafluoroborate (LiBF<sub>4</sub>)) and two high dielectric constant solvents (propylene carbonate (PC) and N,N-dimethylacetamide (DMAC)). This innovative electrolyte formulation has significantly enhanced a notable improvement in the discharge performance of Li/CF<sub>x</sub> batteries. Specifically, Li/CF<sub>x</sub> batteries used of the high-concentration electrolyte demonstrate a higher discharge voltage platform of 2.68 V (compared to 2.50 V with a commercial electrolyte) and a higher energy density of 2175 Wh Kg<sup>−1</sup> (<em>vs</em> 1928 Wh Kg<sup>−1</sup> with a commercial electrolyte) at a current density of 50 mA g<sup>−1</sup>. Notably, the overall performance improvements are largely due to the utilization of a high-concentration electrolyte with high ionic conductivity and regulated solvation structure (with less coordinated solvents), leading to the superior Li<sup>+</sup> transport and facilitating more effective participation of Li<sup>+</sup> and CF<sub>x</sub> in the reaction, thereby boosting capacity. This strategy offers valuable insights into electrolyte design for the improvement of electrochemical performance of Li/CF<sub>x</sub> batteries.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236440"},"PeriodicalIF":8.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143379131","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}

引用次数: 0

Preparation of high performance MnO2 cathode for lithium primary battery through uniform particle size and crystal modulation

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-09 DOI: 10.1016/j.jpowsour.2025.236368

Chenwei Tang, Yinyi Gao, Kai Zhu, Dianxue Cao

{"title":"Preparation of high performance MnO2 cathode for lithium primary battery through uniform particle size and crystal modulation","authors":"Chenwei Tang, Yinyi Gao, Kai Zhu, Dianxue Cao","doi":"10.1016/j.jpowsour.2025.236368","DOIUrl":"10.1016/j.jpowsour.2025.236368","url":null,"abstract":"<div><div>Commercial electrolytic manganese dioxide (EMD) is a widely applicable cathode material in lithium primary batteries (LPBs). Nevertheless, the EMD is limited by several key issues in practical use, which are mainly low electronic conductivity and slow diffusion kinetics. A particle size and crystal type modulation strategy were used to improve the electronic conductivity and ion diffusion kinetics of EMD for the first time. EMD treated with sand milling has a smaller and narrower particle size distribution, which improves reaction kinetics. As analyzed by Rietveld structure refinement, the heat treatment at different temperatures resulted in different degrees of phase transition from γ-MnO<sub>2</sub> to β-MnO<sub>2</sub> in EMD. The β-MnO<sub>2</sub> improved the electrical conductivity of EMD, and the crystal structure defects caused by mixing γ-MnO<sub>2</sub> with β-MnO<sub>2</sub> provided more electrochemical reaction sites. Electrochemical tests demonstrated that the heat-treated EMD after sand milling (SEMD-T) exhibited enhanced electrochemical properties. In particular, the specific capacity of SEMD-380 is 245.7 mAh g<sup>−1</sup> at 0.1 C, which reached 79.8 % of theoretical specific capacity. The maximum energy density of SEMD-380 at 5 C (332.50 Wh kg<sup>−1</sup>) exceeds that of EMD by a factor of three. These findings offer effective guidance for designing high performance electrodes in the future.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236368"},"PeriodicalIF":8.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372620","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}

引用次数: 0

Effect of cylindrical and prismatic configurations on supercapacitor self-discharge and their mitigation approach by external charging strategies

IF 8.1 2区工程技术

Journal of Power Sources Pub Date : 2025-02-09 DOI: 10.1016/j.jpowsour.2025.236406

Weinan Zhao, Zhengxing Zuo, Jingyu Li, Bing-Ang Mei, Huihua Feng, Rui Xiong

{"title":"Effect of cylindrical and prismatic configurations on supercapacitor self-discharge and their mitigation approach by external charging strategies","authors":"Weinan Zhao, Zhengxing Zuo, Jingyu Li, Bing-Ang Mei, Huihua Feng, Rui Xiong","doi":"10.1016/j.jpowsour.2025.236406","DOIUrl":"10.1016/j.jpowsour.2025.236406","url":null,"abstract":"<div><div>Supercapacitors with cylindrical and prismatic configurations exhibit notable differences in self-discharge performance. The experimental results reveal that prismatic supercapacitors demonstrate superior self-discharge performance than their cylindrical counterparts across various holding times. In fact, prismatic supercapacitors experience a smaller absolute voltage drop due to both Ohmic leakage and diffusion contributions when compared to cylindrical supercapacitors.</div><div>For interpreting the differences in terms of Ohmic leakage and diffusion, the result of electochemical impedance spectroscopy reveals that the ratio of internal resistance between the cylindrical supercapacitor and the prismatic supercapacitor is inversely proportional to the ratio of absolute voltage drop due to Ohmic leakage. In addition, the results of numerical models for diffusion show that the reduced self-discharge observed in the prismatic supercapacitor is attributed to a smaller concentration gradient at the end of charging.</div><div>Finally, mitigation of self-discharge for cylindrical and prismatic supercapacitors by external charging strategies is investigated. The results show that charging-holding-resting strategy exhibits the best self-discharge mitigation for cylindrical supercapacitors. On the other hand, both charging-holding-resting-discharging and charging-holding-resting strategies prove to be similarly effective in mitigating self-discharge for prismatic supercapacitors. This could serve as an external approach to effectively mitigate self-discharge of a supercapacitor with specific configuration.</div></div>","PeriodicalId":377,"journal":{"name":"Journal of Power Sources","volume":"633 ","pages":"Article 236406"},"PeriodicalIF":8.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143372624","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}

引用次数: 0