Pub Date : 2024-10-14DOI: 10.1016/j.est.2024.114069
This document discusses energy management in storage systems connected to rural and urban direct current (DC) microgrids, to improve technical, economic, and environmental indicators proposing a mathematical model with three objective functions for a multi-objective approach: minimizing grid operating costs, reducing energy transport losses, and reducing CO emissions. The multi-objective model includes different operational constraints of the DC microgrid. This applies to scenarios of grid connection with both fixed and variable energy costs, as well as to isolated DC microgrids with diesel generators. All of this occurs within an environment with distributed energy resources, specifically photovoltaic generators and energy storage systems. Multi-objective optimization algorithms, such as Particle Swarm Optimization (MPSO), Grasshopper Optimization Algorithm (MGOA), Salp Swarm Algorithm (MSSA), and Ant-Lion Algorithm (MALO), are used to solve multi-objective problems. These algorithms are combined with an hourly power flow method based on successive approximations. The methodologies have been validated through two test scenarios. The first scenario had 27 nodes in a rural environment, while the second had 33 nodes in an urban environment. These scenarios were designed to represent average day generation and energy demand conditions in Colombia. Each scenario involved the integration of three distributed photovoltaic generators and three lithium-ion batteries. The objective was to assess the solution quality and processing times by iteratively running each algorithm 100 times.
{"title":"Techno-economic approach for energy management system: Multi-objective optimization algorithms for energy storage in standalone and grid-connected DC microgrids","authors":"","doi":"10.1016/j.est.2024.114069","DOIUrl":"10.1016/j.est.2024.114069","url":null,"abstract":"<div><div>This document discusses energy management in storage systems connected to rural and urban direct current (DC) microgrids, to improve technical, economic, and environmental indicators proposing a mathematical model with three objective functions for a multi-objective approach: minimizing grid operating costs, reducing energy transport losses, and reducing CO<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> emissions. The multi-objective model includes different operational constraints of the DC microgrid. This applies to scenarios of grid connection with both fixed and variable energy costs, as well as to isolated DC microgrids with diesel generators. All of this occurs within an environment with distributed energy resources, specifically photovoltaic generators and energy storage systems. Multi-objective optimization algorithms, such as Particle Swarm Optimization (MPSO), Grasshopper Optimization Algorithm (MGOA), Salp Swarm Algorithm (MSSA), and Ant-Lion Algorithm (MALO), are used to solve multi-objective problems. These algorithms are combined with an hourly power flow method based on successive approximations. The methodologies have been validated through two test scenarios. The first scenario had 27 nodes in a rural environment, while the second had 33 nodes in an urban environment. These scenarios were designed to represent average day generation and energy demand conditions in Colombia. Each scenario involved the integration of three distributed photovoltaic generators and three lithium-ion batteries. The objective was to assess the solution quality and processing times by iteratively running each algorithm 100 times.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433776","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}
Pub Date : 2024-10-14DOI: 10.1016/j.est.2024.114107
As lithium-ion batteries (LIBs) continue to see pervasive application, the safety issues related to high-temperature accumulation arising from local hot spots have become increasingly critical. Therefore, the development of adaptive cooling measures and temperature management strategies is paramount. This study delves into a liquid cooling device for LIBs, based on a temperature sensitive hydrogel that adapts its flow control. The heat generated from LIBs at a 1C discharge rate is used as the boundary heat source. This research scrutinizes the effects of different flow rates, hot spot dimensions, and hot spot energy intensities on the cooling performance of the hydrogel-infused flow control plate. The results show that, compared with traditional liquid cooling device, the hydrogel augmented device can adjust its hydrogel volume in response to temperature variations, thereby effectively controlling flow distribution and efficiently dissipating heat at hot spot areas. Even with an increase in the hot spot's size and intensity, this adaptive hydrogel-based cooling apparatus maintains a relatively stable maximum temperature and homogeneous temperature distribution. Under various operational conditions, the heat transfer coefficient in scenarios employing the adaptive hydrogel exceeds 8000 W/(m2·K), demonstrating its strong cooling capacity. The results furnish valuable insights into thermal management and provide a solid basis to improve battery safety and promote its commercial applications.
{"title":"A study on the cooling characteristics of radiator for battery hot spots based on temperature hydrogel adaptive valve","authors":"","doi":"10.1016/j.est.2024.114107","DOIUrl":"10.1016/j.est.2024.114107","url":null,"abstract":"<div><div>As lithium-ion batteries (LIBs) continue to see pervasive application, the safety issues related to high-temperature accumulation arising from local hot spots have become increasingly critical. Therefore, the development of adaptive cooling measures and temperature management strategies is paramount. This study delves into a liquid cooling device for LIBs, based on a temperature sensitive hydrogel that adapts its flow control. The heat generated from LIBs at a 1C discharge rate is used as the boundary heat source. This research scrutinizes the effects of different flow rates, hot spot dimensions, and hot spot energy intensities on the cooling performance of the hydrogel-infused flow control plate. The results show that, compared with traditional liquid cooling device, the hydrogel augmented device can adjust its hydrogel volume in response to temperature variations, thereby effectively controlling flow distribution and efficiently dissipating heat at hot spot areas. Even with an increase in the hot spot's size and intensity, this adaptive hydrogel-based cooling apparatus maintains a relatively stable maximum temperature and homogeneous temperature distribution. Under various operational conditions, the heat transfer coefficient in scenarios employing the adaptive hydrogel exceeds 8000 W/(m<sup>2</sup>·K), demonstrating its strong cooling capacity. The results furnish valuable insights into thermal management and provide a solid basis to improve battery safety and promote its commercial applications.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433777","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}
Pub Date : 2024-10-14DOI: 10.1016/j.est.2024.114037
To expedite the construction and implementation of compressed air energy storage (CAES) in under- ground salt caverns (USCs), conducting a thorough stability assessment is crucial to ensure the safe operation of underground salt cavern gas storage (SCGS). Herein we present a theoretical model for the volumetric inversion of two-well-horizontal (TWH) caverns, based on salt extraction, salt layer characteristics, and interlayer ratio, using data from a low-grade salt mine in Feicheng City, China. In addition, we simulated the volume loss rate (VLR), displacement, and plastic zone volume (PZV) for various levels of high sediment content (SC) (50 %, 60 %, 70 %, 80 %, 90 %) and internal air pressure (IAP) (8.1 MPa, 9.45 MPa, 21.6 MPa) in the roof, waist, and connected areas of both high and low caverns within the TWH-cavern. The results reveal that the creep characteristics of the high cavern are more pronounced, and the combined effects of SC and IAP effectively limit roof deformation. How- ever, the displacement of the high cavern waist increases by 0.028 m (IAP = 8.1 MPa) and 0.006 m (IAP = 21.6 MPa) as SC rises from 80 % to 90 %. In the connected area, displacement values increase from 0.634 m to 0.852 m (IAP = 8.1 MPa) as SC increases from 50 % to 90 %. These findings emphasize that the sediment surface is a criterion for measuring whether the increase in SC inhibits or promotes cavern deformation. The cavern roof remains the most critical component for ensuring the safe operation of SC-CAES. Therefore, this study provides a theoretical basis for evaluating the safety of TWH-cavern energy storage in low-grade salt rock reservoirs and expands the potential sites for SC-CAES.
{"title":"Comprehensive safety assessment of two-well-horizontal caverns with sediment space for compressed air energy storage in low-grade salt rocks","authors":"","doi":"10.1016/j.est.2024.114037","DOIUrl":"10.1016/j.est.2024.114037","url":null,"abstract":"<div><div>To expedite the construction and implementation of compressed air energy storage (CAES) in under- ground salt caverns (USCs), conducting a thorough stability assessment is crucial to ensure the safe operation of underground salt cavern gas storage (SCGS). Herein we present a theoretical model for the volumetric inversion of two-well-horizontal (TWH) caverns, based on salt extraction, salt layer characteristics, and interlayer ratio, using data from a low-grade salt mine in Feicheng City, China. In addition, we simulated the volume loss rate (VLR), displacement, and plastic zone volume (PZV) for various levels of high sediment content (SC) (50 %, 60 %, 70 %, 80 %, 90 %) and internal air pressure (IAP) (8.1 MPa, 9.45 MPa, 21.6 MPa) in the roof, waist, and connected areas of both high and low caverns within the TWH-cavern. The results reveal that the creep characteristics of the high cavern are more pronounced, and the combined effects of SC and IAP effectively limit roof deformation. How- ever, the displacement of the high cavern waist increases by 0.028 m (IAP = 8.1 MPa) and 0.006 m (IAP = 21.6 MPa) as SC rises from 80 % to 90 %. In the connected area, displacement values increase from 0.634 m to 0.852 m (IAP = 8.1 MPa) as SC increases from 50 % to 90 %. These findings emphasize that the sediment surface is a criterion for measuring whether the increase in SC inhibits or promotes cavern deformation. The cavern roof remains the most critical component for ensuring the safe operation of SC-CAES. Therefore, this study provides a theoretical basis for evaluating the safety of TWH-cavern energy storage in low-grade salt rock reservoirs and expands the potential sites for SC-CAES.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433774","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}
Pub Date : 2024-10-14DOI: 10.1016/j.est.2024.114140
The present study investigates effect of reduced graphene oxide (rGO) mass dispersoid @ 25, 50, 75, and 100 mg through in-situ process into Metal Organic Framework based Nickel Phosphate (MOFNP) synthesized by facile microwave technique. The XRD study confirms monoclinic crystalline geometry and 50 mg rGO dispersed MOFNP (MOFNPG2) composite has shown increase in crystallinity. SEM shows rectangular morphology for MOFNPG2 and Raman studies show ID/IG ratio of 1.01 for this composite revealing rGO coordination with MOFNP. BET studies reveal higher specific surface area (59.75 m2 g−1) for MOFNPG2 and exhibits mesoporosity (3.14 nm) with type-IV Langmuir isotherm. The deconvoluted XPS spectra confirms oxidation states and chemical compositions of MOFNPG2. The CV profile identifies maximum oxidation for MOFNPG2, revealing EDLC / pseudocapacitance contribution and exhibiting higher specific capacitance of 854 F g−1 @ 1 A g−1. The Full-Cell Device (FCD) MOFNPG2//rGO registers 175 F g−1 @ 1 A g−1 and energy density 79 Wh kg−1. The Resr is lower (0.19 Ω cm−2) for FCD which improvises electrode-electrolyte kinetics and results in enhanced conductivity for high energy density supercapacitor applications.
{"title":"Exploratory mass dispersoid rGO in-situ influence on nickel phosphate-trimesic acid metal-organic framework for higher energy density hybrid supercapacitors","authors":"","doi":"10.1016/j.est.2024.114140","DOIUrl":"10.1016/j.est.2024.114140","url":null,"abstract":"<div><div>The present study investigates effect of reduced graphene oxide (rGO) mass dispersoid @ 25, 50, 75, and 100 mg through in-situ process into Metal Organic Framework based Nickel Phosphate (MOFNP) synthesized by facile microwave technique. The XRD study confirms monoclinic crystalline geometry and 50 mg rGO dispersed MOFNP (MOFNPG2) composite has shown increase in crystallinity. SEM shows rectangular morphology for MOFNPG2 and Raman studies show I<sub>D</sub>/I<sub>G</sub> ratio of 1.01 for this composite revealing rGO coordination with MOFNP. BET studies reveal higher specific surface area (59.75 m<sup>2</sup> g<sup>−1</sup>) for MOFNPG2 and exhibits mesoporosity (3.14 nm) with type-IV Langmuir isotherm. The deconvoluted XPS spectra confirms oxidation states and chemical compositions of MOFNPG2. The CV profile identifies maximum oxidation for MOFNPG2, revealing EDLC / pseudocapacitance contribution and exhibiting higher specific capacitance of 854 F g<sup>−1</sup> @ 1 A g<sup>−1</sup>. The Full-Cell Device (FCD) MOFNPG2//rGO registers 175 F g<sup>−1</sup> @ 1 A g<sup>−1</sup> and energy density 79 Wh kg<sup>−1</sup>. The R<sub>esr</sub> is lower (0.19 Ω cm<sup>−2</sup>) for FCD which improvises electrode-electrolyte kinetics and results in enhanced conductivity for high energy density supercapacitor applications.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433775","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}
Pub Date : 2024-10-14DOI: 10.1016/j.est.2024.114128
The rational surface reconstruction of component heterointerfaces is an effective strategy for boosting the electrochemical activity and structural stability of asymmetric supercapacitors. In this study, a Co3O4/rGO (cobalt oxide/reduced graphene oxide(rGO)) heterostructure was designed using a hydrothermal and annealing strategy. Owing to its abundant electroactive sites, accelerated diffusion reaction kinetics, and strong OH−adsorption capability, the optimized Co3O4/rGO composite delivered an ultrahigh capacitance of 273.3 F/g at 1 A/g. Additionally, density functional theory (DFT) calculations verified the significant charge transfer from Co3O4 to rGO near the heterointerface, achieving obvious charge redistribution and the formation of a space-charge layer. This optimization enhances significantly optimizes OH− adsorption and diffusion and improves electrical conductivity, leading to the excellent electrochemical performance of the surface-reconstructed Co3O4/rGO. More importantly, the all-solid-state asymmetric supercapacitor Co3O4/rGO//AC (activated carbon) demonstrated an exceptional energy density of 16.47 Wh/kg at a power density of 599 W/kg, along with excellent cycling stability, retaining 91.0 % capacitance after 5000 cycles. Overall, this study provides an effective approach for designing surface-reconstructed heterointerfaces to achieve remarkable electrochemical performance and ensure structural integrity, showcasing significant potential for practical applications in the energy storage market.
{"title":"Surface reconstruction of Co3O4/rGO heterointerface enabling high-performance asymmetric supercapacitors","authors":"","doi":"10.1016/j.est.2024.114128","DOIUrl":"10.1016/j.est.2024.114128","url":null,"abstract":"<div><div>The rational surface reconstruction of component heterointerfaces is an effective strategy for boosting the electrochemical activity and structural stability of asymmetric supercapacitors. In this study, a Co<sub>3</sub>O<sub>4</sub>/rGO (cobalt oxide/reduced graphene oxide(rGO)) heterostructure was designed using a hydrothermal and annealing strategy. Owing to its abundant electroactive sites, accelerated diffusion reaction kinetics, and strong OH<sup>−</sup>adsorption capability, the optimized Co<sub>3</sub>O<sub>4</sub>/rGO composite delivered an ultrahigh capacitance of 273.3 F/g at 1 A/g. Additionally, density functional theory (DFT) calculations verified the significant charge transfer from Co<sub>3</sub>O<sub>4</sub> to rGO near the heterointerface, achieving obvious charge redistribution and the formation of a space-charge layer. This optimization enhances significantly optimizes OH<sup>−</sup> adsorption and diffusion and improves electrical conductivity, leading to the excellent electrochemical performance of the surface-reconstructed Co<sub>3</sub>O<sub>4</sub>/rGO. More importantly, the all-solid-state asymmetric supercapacitor Co<sub>3</sub>O<sub>4</sub>/rGO//AC (activated carbon) demonstrated an exceptional energy density of 16.47 Wh/kg at a power density of 599 W/kg, along with excellent cycling stability, retaining 91.0 % capacitance after 5000 cycles. Overall, this study provides an effective approach for designing surface-reconstructed heterointerfaces to achieve remarkable electrochemical performance and ensure structural integrity, showcasing significant potential for practical applications in the energy storage market.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433773","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}
Pub Date : 2024-10-13DOI: 10.1016/j.est.2024.114057
Due to the extensive pollution generated by conventional fuel-based power systems, there has been a significant shift in global focus toward increasing the adoption of renewable energy sources (RESs) through renewable-based distributed generation (DG), particularly wind and solar photovoltaic (PV) systems. Additionally, the electrification of the automotive sector, aimed at reducing pollution, is driving a rapid increase in electric vehicles (EVs). A critical element of this transition is the development of efficient infrastructure for plug-in electric vehicle parking lots (PEV-PLs). A collaborative planning model is essential to address the impact of integrating RESs and PEV-PLs into the electric power distribution system (DS) over the long term. This paper introduces a long-term mixed-integer non-linear (MINL) optimization planning model designed to optimize the planning and operation of RESs, including wind and PV sources, alongside PEV-PLs infrastructure. The goal is to increase the penetration of renewable energy and EVs within the DS while adhering to security constraints. The optimization model features three non-linear, incompatible objective functions: minimizing overall strategic expected investment, maintenance, emission, and operational costs; long-term power loss; and voltage deviation. Moreover, to ensure realism, the model incorporates uncertainties related to stochastic variables such as the intermittent nature of RESs, EV energy and time variables, loads, and energy price fluctuations, using Monte Carlo Simulation (MCS) and the backward reduction method (BRM). A hybrid optimization algorithm addresses the proposed objectives, combining the non-dominated sorting genetic algorithm (NSGA-II) and multi-objective particle swarm optimization (MOPSO) to minimize the three distinct objective functions concurrently. The effectiveness of the planning model is validated using the 69-bus benchmark test system, with four configurations tested: case 1 (the base case), case 2 (the base case with RESs (wind and PV)), case 3 (the base case with RESs and PEV-PLs), and case 4 (the base case with RESs, PEV-PLs, and a higher number of EVs). The impact of RESs on DS operation, PEV-PLs on RES penetration levels and DS operation, and the effect of increased EV penetration on the integrated capacity of RESs and DS operation are thoroughly investigated. Simulation results demonstrate that the optimal integration of 5 PEV-PLs, accommodating a fleet of 107 PEVs with wind and PV DGs, increases the RES penetration level from 3.35 MVA to 3.85 MVA compared to the case with RESs alone. Moreover, integrating PEV-PLs with RESs results in a 51.00 % reduction in overall operational costs, a 37.55 % reduction in overall planning and operation costs, a 52.82 % reduction in total carbon emissions, and a 45.85 % reduction in total voltage deviation.
{"title":"Long-term optimal planning for renewable based distributed generators and plug-in electric vehicles parking lots toward higher penetration of green energy technology","authors":"","doi":"10.1016/j.est.2024.114057","DOIUrl":"10.1016/j.est.2024.114057","url":null,"abstract":"<div><div>Due to the extensive pollution generated by conventional fuel-based power systems, there has been a significant shift in global focus toward increasing the adoption of renewable energy sources (RESs) through renewable-based distributed generation (DG), particularly wind and solar photovoltaic (PV) systems. Additionally, the electrification of the automotive sector, aimed at reducing pollution, is driving a rapid increase in electric vehicles (EVs). A critical element of this transition is the development of efficient infrastructure for plug-in electric vehicle parking lots (PEV-PLs). A collaborative planning model is essential to address the impact of integrating RESs and PEV-PLs into the electric power distribution system (DS) over the long term. This paper introduces a long-term mixed-integer non-linear (MINL) optimization planning model designed to optimize the planning and operation of RESs, including wind and PV sources, alongside PEV-PLs infrastructure. The goal is to increase the penetration of renewable energy and EVs within the DS while adhering to security constraints. The optimization model features three non-linear, incompatible objective functions: minimizing overall strategic expected investment, maintenance, emission, and operational costs; long-term power loss; and voltage deviation. Moreover, to ensure realism, the model incorporates uncertainties related to stochastic variables such as the intermittent nature of RESs, EV energy and time variables, loads, and energy price fluctuations, using Monte Carlo Simulation (MCS) and the backward reduction method (BRM). A hybrid optimization algorithm addresses the proposed objectives, combining the non-dominated sorting genetic algorithm (NSGA-II) and multi-objective particle swarm optimization (MOPSO) to minimize the three distinct objective functions concurrently. The effectiveness of the planning model is validated using the 69-bus benchmark test system, with four configurations tested: case 1 (the base case), case 2 (the base case with RESs (wind and PV)), case 3 (the base case with RESs and PEV-PLs), and case 4 (the base case with RESs, PEV-PLs, and a higher number of EVs). The impact of RESs on DS operation, PEV-PLs on RES penetration levels and DS operation, and the effect of increased EV penetration on the integrated capacity of RESs and DS operation are thoroughly investigated. Simulation results demonstrate that the optimal integration of 5 PEV-PLs, accommodating a fleet of 107 PEVs with wind and PV DGs, increases the RES penetration level from 3.35 MVA to 3.85 MVA compared to the case with RESs alone. Moreover, integrating PEV-PLs with RESs results in a 51.00 % reduction in overall operational costs, a 37.55 % reduction in overall planning and operation costs, a 52.82 % reduction in total carbon emissions, and a 45.85 % reduction in total voltage deviation.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142416997","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}
Pub Date : 2024-10-13DOI: 10.1016/j.est.2024.114033
Nickel-rich polycrystalline LiNixCoyMn1-x-yO2 (PC-NCM, 0.8 ≤ x < 1) particles suffer capacity degradation due to intergranular cracks, which catalyze side reactions at fresh interfaces, diminishing battery performance. Understanding the mechanisms behind crack evolution is essential for mitigating these issues. Real-time crack observation is crucial for this understanding, yet long-term monitoring remains unachieved. This study develops a versatile method using an optical in-situ reaction cell, modified from a coin cell structure, to enable long-term, real-time tracking of volume changes, crack evolution and lithium-ion diffusion in the particle. This method has provided new insights into the evolution of intergranular cracks and mechanisms in PC-NCM811 particles. Intergranular cracks can be categorized into main cracks, microcracks and cracks at the boundaries of inactive domains based on the stress origin. Main cracks stem from strain mismatches caused by asynchronous domains during initial activation, while their subsequent propagation is driven by alternating stresses from cycling. The initiation of microcracks is caused by stress concentration at grain boundaries due to abrupt volume contraction during charging process. Volume changes along the a-axis exacerbate the irreversible propagation of these microcracks at a high state of charge. Optical imaging shows regions with limited lithium-ion diffusion align with boundary cracks caused by uneven lithium-ion concentrations at high C-rate. These findings emphasize the value of long-term, real-time observation for understanding electrochemical-mechanical interactions. The observation and analysis method can be applied to investigate and evaluate the crack evolution of various materials under different conditions, facilitating the optimization of material design and the formulation of effective cycling protocols.
富镍多晶 LiNixCoyMn1-x-yO2（PC-NCM，0.8 ≤ x <1）颗粒由于晶间裂纹而导致容量下降，这种裂纹会催化新鲜界面的副反应，从而降低电池性能。了解裂纹演变背后的机制对于缓解这些问题至关重要。实时裂纹观测对于理解裂纹至关重要，但长期监测仍未实现。本研究开发了一种多功能方法，使用一种从纽扣电池结构改进而来的光学原位反应电池，对颗粒中的体积变化、裂纹演变和锂离子扩散进行长期、实时跟踪。这种方法为了解 PC-NCM811 颗粒中晶间裂纹的演变和机制提供了新的视角。根据应力来源，晶间裂纹可分为主裂纹、微裂纹和非活动域边界裂纹。主裂纹源于初始活化过程中不同步畴引起的应变不匹配，而随后的扩展则是由循环产生的交变应力驱动的。微裂纹的产生是由于充填过程中体积突然收缩导致晶界应力集中造成的。沿 a 轴的体积变化加剧了这些微裂纹在高电荷状态下的不可逆传播。光学成像显示，锂离子扩散受限的区域与高 C 率下锂离子浓度不均造成的边界裂纹相一致。这些发现强调了长期、实时观测对于理解电化学-机械相互作用的价值。这种观察和分析方法可用于研究和评估各种材料在不同条件下的裂纹演变，有助于优化材料设计和制定有效的循环方案。
{"title":"Study on the intergranular cracks evolution and mechanisms in PC-NCM811 particles through long-term real-time observation","authors":"","doi":"10.1016/j.est.2024.114033","DOIUrl":"10.1016/j.est.2024.114033","url":null,"abstract":"<div><div>Nickel-rich polycrystalline LiNi<sub>x</sub>Co<sub>y</sub>Mn<sub>1-x-y</sub>O<sub>2</sub> (PC-NCM, 0.8 ≤ x < 1) particles suffer capacity degradation due to intergranular cracks, which catalyze side reactions at fresh interfaces, diminishing battery performance. Understanding the mechanisms behind crack evolution is essential for mitigating these issues. Real-time crack observation is crucial for this understanding, yet long-term monitoring remains unachieved. This study develops a versatile method using an optical in-situ reaction cell, modified from a coin cell structure, to enable long-term, real-time tracking of volume changes, crack evolution and lithium-ion diffusion in the particle. This method has provided new insights into the evolution of intergranular cracks and mechanisms in PC-NCM811 particles. Intergranular cracks can be categorized into main cracks, microcracks and cracks at the boundaries of inactive domains based on the stress origin. Main cracks stem from strain mismatches caused by asynchronous domains during initial activation, while their subsequent propagation is driven by alternating stresses from cycling. The initiation of microcracks is caused by stress concentration at grain boundaries due to abrupt volume contraction during charging process. Volume changes along the <em>a</em>-axis exacerbate the irreversible propagation of these microcracks at a high state of charge. Optical imaging shows regions with limited lithium-ion diffusion align with boundary cracks caused by uneven lithium-ion concentrations at high C-rate. These findings emphasize the value of long-term, real-time observation for understanding electrochemical-mechanical interactions. The observation and analysis method can be applied to investigate and evaluate the crack evolution of various materials under different conditions, facilitating the optimization of material design and the formulation of effective cycling protocols.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417534","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}
Pub Date : 2024-10-13DOI: 10.1016/j.est.2024.114034
The structural, photoluminescence, dielectric, optical, and conductivity characteristics of polymer nanocomposites (PNCs) films made of polyvinylpyrrolidone (PVP) and poly(vinylidene fluoride) doped with tin oxide nanoparticles (SnO2 NPs) are reported in detail in this research. Using the casting approach, PVDF/PVP films doped with SnO2 (0.0, 0.5, 2.0, 4.0, and 7.0 wt%) were created. X-ray diffraction (XRD) study was employed to examine the effect of nanoparticles on polymer structure of the films. Using XRD data, the impact of the weight percentage of nanofiller on crystalline size and micro-strain has been investigated. XRD also ascertained the mean particle size of the SnO2 NPs at 15 nm. The complexation and interactions between the nanofiller and the PVDF/PVP reactive groups were demonstrated by the Fourier transform infrared (FTIR) transmittance spectra. The absorbance spectra from the UV–visible spectrophotometer were used to study optical characteristics. The direct/indirect band gaps for pure blend were decreased from 5.06/4.67 eV to 4.27/3.46 eV for PVDF/PVP-4.0 wt%SnO2 NPs, while, the values of EU of the films increased with the adding of SnO2 NPs in the polymer matrix. The produced nanocomposite's PL spectra were examined for optical properties, and at 430 nm, a broadened peak of the PVDF/PVP polymer was discovered. When SnO2 nanofiller were mixed, a shift in wavelength was noticed, albeit the intensity was greatly diminished. Impedance spectroscopy has been used to examine the films' AC electrical conductivity at frequencies between 102 and 107 Hz. According to Jonscher's rule, the blend's AC electrical conductivity grows as the concentration of SnO2 NPs does. Furthermore, it has been shown that an increase in nanoparticle concentration raises the dielectric constant and composite dielectric loss. Because the 4 wt% sample has the highest AC conductivity, dielectric constant, and optical characteristics, it can be used to create flexible electrochemical devices and optoelectronic devices with improved charge-storing capacities.
{"title":"Study of structural, optical, photoluminescence, dielectric, and conductivity properties of PVDF/PVP-SnO2 nanocomposites for optoelectronics and micro-supercapacitors","authors":"","doi":"10.1016/j.est.2024.114034","DOIUrl":"10.1016/j.est.2024.114034","url":null,"abstract":"<div><div>The structural, photoluminescence, dielectric, optical, and conductivity characteristics of polymer nanocomposites (PNCs) films made of polyvinylpyrrolidone (PVP) and poly(vinylidene fluoride) doped with tin oxide nanoparticles (SnO<sub>2</sub> NPs) are reported in detail in this research. Using the casting approach, PVDF/PVP films doped with SnO<sub>2</sub> (0.0, 0.5, 2.0, 4.0, and 7.0 wt%) were created. X-ray diffraction (XRD) study was employed to examine the effect of nanoparticles on polymer structure of the films. Using XRD data, the impact of the weight percentage of nanofiller on crystalline size and micro-strain has been investigated. XRD also ascertained the mean particle size of the SnO<sub>2</sub> NPs at 15 nm. The complexation and interactions between the nanofiller and the PVDF/PVP reactive groups were demonstrated by the Fourier transform infrared (FTIR) transmittance spectra. The absorbance spectra from the UV–visible spectrophotometer were used to study optical characteristics. The direct/indirect band gaps for pure blend were decreased from 5.06/4.67 eV to 4.27/3.46 eV for PVDF/PVP-4.0 wt%SnO<sub>2</sub> NPs, while, the values of E<sub>U</sub> of the films increased with the adding of SnO<sub>2</sub> NPs in the polymer matrix. The produced nanocomposite's PL spectra were examined for optical properties, and at 430 nm, a broadened peak of the PVDF/PVP polymer was discovered. When SnO<sub>2</sub> nanofiller were mixed, a shift in wavelength was noticed, albeit the intensity was greatly diminished. Impedance spectroscopy has been used to examine the films' AC electrical conductivity at frequencies between 10<sup>2</sup> and 10<sup>7</sup> Hz. According to Jonscher's rule, the blend's AC electrical conductivity grows as the concentration of SnO<sub>2</sub> NPs does. Furthermore, it has been shown that an increase in nanoparticle concentration raises the dielectric constant and composite dielectric loss. Because the 4 wt% sample has the highest AC conductivity, dielectric constant, and optical characteristics, it can be used to create flexible electrochemical devices and optoelectronic devices with improved charge-storing capacities.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417087","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}
Pub Date : 2024-10-13DOI: 10.1016/j.est.2024.114038
To break through the variety limitation on active sites as well as molecular configuration of conventional polymeric chains, a novel two-dimensional binder is proposed to support Si anode via modifying oxidized graphene by p-aminobenzenesulfonic acid. Based on its flexible 2D structure, with the assistance of citric acid as the additive, this functionalized graphene oxide exhibits strong binding effect to anchor Si particles through strong and enriched point-to-plane interactions, which therefore effectively help maintain a pliable and robust 3D structure for the electrode when suffering from severe Si volume effect. Moreover, this binder introduces multiple Li ion transport paths by its sulfonated groups and defects etched on GO layers, so that can remarkably promote the Li+ diffusion rate in the electrode. Benefiting from this novel binder, the Si anodes demonstrate a high capacity of 1590 mAh g−1 after 400 cycles under the current density of 1 A g−1. The Li ion diffusion rate increases around one order of magnitude after the sulfonated functionalization of the binder. To sum up, this work verifies noticeable advantages of the GO-based binder on its flexible structure, enriched chemical properties and multi-functionalized potential, revealing a promising prospective of this two-dimensional binder on high performance Si anode applications.
为了突破传统聚合物链对活性位点和分子构型的限制，我们提出了一种新型二维粘合剂，通过对氨基苯磺酸对氧化石墨烯进行改性来支撑硅阳极。基于其柔韧的二维结构，在柠檬酸作为添加剂的辅助下，这种功能化氧化石墨烯通过强大而丰富的点对平面相互作用，对锚定硅颗粒表现出很强的结合力，因此在受到严重的硅体积效应影响时，能有效帮助电极保持柔韧而坚固的三维结构。此外，这种粘合剂通过其磺化基团和蚀刻在 GO 层上的缺陷引入了多条锂离子传输路径，从而显著提高了电极中的锂离子扩散速率。得益于这种新型粘合剂，硅阳极在电流密度为 1 A g-1 的条件下循环 400 次后，显示出 1590 mAh g-1 的高容量。粘合剂磺化官能化后，锂离子扩散率提高了约一个数量级。总之，这项工作验证了基于 GO 的粘合剂在柔性结构、丰富的化学特性和多功能化潜力方面的显著优势，揭示了这种二维粘合剂在高性能硅负极应用中的广阔前景。
{"title":"A novel two-dimensional binder based on functionalized-graphene oxide for high performance Si anodes of Li ion batteries","authors":"","doi":"10.1016/j.est.2024.114038","DOIUrl":"10.1016/j.est.2024.114038","url":null,"abstract":"<div><div>To break through the variety limitation on active sites as well as molecular configuration of conventional polymeric chains, a novel two-dimensional binder is proposed to support Si anode via modifying oxidized graphene by p-aminobenzenesulfonic acid. Based on its flexible 2D structure, with the assistance of citric acid as the additive, this functionalized graphene oxide exhibits strong binding effect to anchor Si particles through strong and enriched point-to-plane interactions, which therefore effectively help maintain a pliable and robust 3D structure for the electrode when suffering from severe Si volume effect. Moreover, this binder introduces multiple Li ion transport paths by its sulfonated groups and defects etched on GO layers, so that can remarkably promote the Li<sup>+</sup> diffusion rate in the electrode. Benefiting from this novel binder, the Si anodes demonstrate a high capacity of 1590 mAh g<sup>−1</sup> after 400 cycles under the current density of 1 A g<sup>−1</sup>. The Li ion diffusion rate increases around one order of magnitude after the sulfonated functionalization of the binder. To sum up, this work verifies noticeable advantages of the GO-based binder on its flexible structure, enriched chemical properties and multi-functionalized potential, revealing a promising prospective of this two-dimensional binder on high performance Si anode applications.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417305","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}
Pub Date : 2024-10-13DOI: 10.1016/j.est.2024.114036
The drastic depletion of fossil fuels and ever increasing environmental pollution are the two key factors to search for alternative renewable energy resources. Nowadays, hybrid Electrochemical Energy Storage device (EES) known as supercapattery is considered as the prominent green energy source, because of having the merits of both supercapacitors and batteries. In the present work, two different hybrid electrode materials namely Bismuth oxybromide (BiOBr)/graphitic carbon nitride (g-C3N4) [BBGN] and Bismuth oxychloride (BiOCl)/graphitic carbon nitride (g-C3N4) [BCGN] were synthesized using a facile precipitation method where BiOBr (BB)/BiOCl (BC) was decorated at the surface of g-C3N4 (GCN). The prepared hybrid electrodes BBGN and BCGN exhibit high specific capacity of 1248.84 C/g and 1022.67 C/g at a current density of 1 A/g, compared to BB, BC and GCN electrodes. The sheet like morphology of BBGN and BCGN promotes fast ion transfer and thereby enhances the power density and energy density. The fabricated BiOBr/g-C3N4||BiOBr/g-C3N4 symmetric supercapattery (SSC) device delivered an excellent energy density of 22.5 Wh/kg than BiOBr/g-C3N4||g-C3N4 asymmetric supercapattery (ASC) device (14.76 Wh/kg). The performance of SSC device was demonstrated using a 2 V red light emitting diode (LED) and it could able to power for 5 min 35 s. Hence, these results authenticate that the BiOBr/g-C3N4 nanocomposite may serve as a promising electrode material for supercapattery applications in the realm of renewable energy.
{"title":"Preparation and characterization of BiOBr/g-C3N4 and BiOCl/g-C3N4 electrode materials for high-performance asymmetric (BiOBr/g-C3N4||g-C3N4) and symmetric (BiOBr/g-C3N4||BiOBr/g-C3N4) supercapattery devices","authors":"","doi":"10.1016/j.est.2024.114036","DOIUrl":"10.1016/j.est.2024.114036","url":null,"abstract":"<div><div>The drastic depletion of fossil fuels and ever increasing environmental pollution are the two key factors to search for alternative renewable energy resources. Nowadays, hybrid Electrochemical Energy Storage device (EES) known as supercapattery is considered as the prominent green energy source, because of having the merits of both supercapacitors and batteries. In the present work, two different hybrid electrode materials namely Bismuth oxybromide (BiOBr)/graphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) [BBGN] and Bismuth oxychloride (BiOCl)/graphitic carbon nitride (g-C<sub>3</sub>N<sub>4</sub>) [BCGN] were synthesized using a facile precipitation method where BiOBr (BB)/BiOCl (BC) was decorated at the surface of g-C<sub>3</sub>N<sub>4</sub> (GCN). The prepared hybrid electrodes BBGN and BCGN exhibit high specific capacity of 1248.84 C/g and 1022.67 C/g at a current density of 1 A/g, compared to BB, BC and GCN electrodes. The sheet like morphology of BBGN and BCGN promotes fast ion transfer and thereby enhances the power density and energy density. The fabricated BiOBr/g-C<sub>3</sub>N<sub>4</sub>||BiOBr/g-C<sub>3</sub>N<sub>4</sub> symmetric supercapattery (SSC) device delivered an excellent energy density of 22.5 Wh/kg than BiOBr/g-C<sub>3</sub>N<sub>4</sub>||g-C<sub>3</sub>N<sub>4</sub> asymmetric supercapattery (ASC) device (14.76 Wh/kg). The performance of SSC device was demonstrated using a 2 V red light emitting diode (LED) and it could able to power for 5 min 35 s. Hence, these results authenticate that the BiOBr/g-C<sub>3</sub>N<sub>4</sub> nanocomposite may serve as a promising electrode material for supercapattery applications in the realm of renewable energy.</div></div>","PeriodicalId":15942,"journal":{"name":"Journal of energy storage","volume":null,"pages":null},"PeriodicalIF":8.9,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142417533","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}
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