Shuai Jiang, Fangyuan Shi, Jie Li, Yongjun Pan, Honggang Li, Binghe Liu
Prismatic lithium-ion batteries (LIBs) are becoming the most prevalent battery type in electric vehicles, and their mechanical safety is garnering increased attention. Understanding the mechanical response and internal short circuit (ISC) of prismatic LIBs during dynamic impact is important for enhancing the safety and reliability of electric vehicles. Thanks to the pioneer's works on the cylindrical and pouch LIB, prismatic LIB can draw on relevant experimental and numerical modeling methods. However, there is still a lack of research on the dynamic effects of prismatic LIB in various loading directions. To address this disparity, the current research utilizes quasi-static and dynamic impact experiments on prismatic LIBs as a foundation. First, the mechanical response of a sizable prismatic LIB under quasi-static conditions and the dynamic effects are examined when subjected to mechanical abuse from various loading directions. Second, an anisotropic finite element model that considers dynamic strain rates are developed, enabling it to accurately represent the mechanical response to both quasi-static and dynamic impact loads. At last, we performed an analysis of ISC occurring under dynamic loading conditions combining the experimental and simulated results. The experimental results as well as the established model can provide reference for the safe design, application, and analysis of prismatic LIBs.
{"title":"Internal short circuit and dynamic response of large-format prismatic lithium-ion battery under mechanical abuse","authors":"Shuai Jiang, Fangyuan Shi, Jie Li, Yongjun Pan, Honggang Li, Binghe Liu","doi":"10.1115/1.4066056","DOIUrl":"https://doi.org/10.1115/1.4066056","url":null,"abstract":"\u0000 Prismatic lithium-ion batteries (LIBs) are becoming the most prevalent battery type in electric vehicles, and their mechanical safety is garnering increased attention. Understanding the mechanical response and internal short circuit (ISC) of prismatic LIBs during dynamic impact is important for enhancing the safety and reliability of electric vehicles. Thanks to the pioneer's works on the cylindrical and pouch LIB, prismatic LIB can draw on relevant experimental and numerical modeling methods. However, there is still a lack of research on the dynamic effects of prismatic LIB in various loading directions. To address this disparity, the current research utilizes quasi-static and dynamic impact experiments on prismatic LIBs as a foundation. First, the mechanical response of a sizable prismatic LIB under quasi-static conditions and the dynamic effects are examined when subjected to mechanical abuse from various loading directions. Second, an anisotropic finite element model that considers dynamic strain rates are developed, enabling it to accurately represent the mechanical response to both quasi-static and dynamic impact loads. At last, we performed an analysis of ISC occurring under dynamic loading conditions combining the experimental and simulated results. The experimental results as well as the established model can provide reference for the safe design, application, and analysis of prismatic LIBs.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141801759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zhenhai Gao, S. Rao, Zien Zhang, Yupeng Wang, Yang Xiao, Quan Yuan, Weifeng Li
Enhancing the safety performance of high-energy-density lithium-ion batteries are crucial for their widespread adoption. Herein, a cost-effective and highly efficient electrolyte additive, Triphenyl phosphate (TPP), demonstrates flame-retardant properties by scavenging hydrogen radicals in the flame, thereby inhibiting chain reactions and flame propagation to enhance the safety performance of graphite/LiNi0.8Co0.1Mn0.1O2 (NCM811) pouch cells. The results reveal that the capacity retention of cells without flame retardants, and those with the addition of 1 wt%, 3 wt%, 5 wt%, and 10 wt% TPP, is 96.4%, 92.1%, 84.15%, 71.0%, and 15.4% (1/2C 300 cycles), respectively. Furthermore, compared to cells without flame retardants, the highest temperature during thermal runaway decreases by 10.7%, 28.9%, 36.8%, and 40.4% with the addition of 1 wt%, 3 wt%, 5 wt%, and 10 wt% TPP, respectively. Through comprehensive analysis of the impact of flame-retardant additives on battery electrochemical performance and safety, it is determined that the optimal addition amount is 3 wt%. At this level, there are no significant flames during battery abuse, the triggering temperature for thermal runaway increases by 26.6°C, nd the maximum temperature decreases by 175°C. Moreover, even after 300 cycles at 1/2C, a capacity of 814.5mAh g-1 is retained, with a capacity retention rate of 84.1%. This study provides valuable insights into the mitigation of thermal runaway in high-energy-density power batteries.
{"title":"Thermal runaway characteristics of Ni-rich lithium-ion batteries employing TPP-based electrolytes","authors":"Zhenhai Gao, S. Rao, Zien Zhang, Yupeng Wang, Yang Xiao, Quan Yuan, Weifeng Li","doi":"10.1115/1.4066013","DOIUrl":"https://doi.org/10.1115/1.4066013","url":null,"abstract":"\u0000 Enhancing the safety performance of high-energy-density lithium-ion batteries are crucial for their widespread adoption. Herein, a cost-effective and highly efficient electrolyte additive, Triphenyl phosphate (TPP), demonstrates flame-retardant properties by scavenging hydrogen radicals in the flame, thereby inhibiting chain reactions and flame propagation to enhance the safety performance of graphite/LiNi0.8Co0.1Mn0.1O2 (NCM811) pouch cells. The results reveal that the capacity retention of cells without flame retardants, and those with the addition of 1 wt%, 3 wt%, 5 wt%, and 10 wt% TPP, is 96.4%, 92.1%, 84.15%, 71.0%, and 15.4% (1/2C 300 cycles), respectively. Furthermore, compared to cells without flame retardants, the highest temperature during thermal runaway decreases by 10.7%, 28.9%, 36.8%, and 40.4% with the addition of 1 wt%, 3 wt%, 5 wt%, and 10 wt% TPP, respectively. Through comprehensive analysis of the impact of flame-retardant additives on battery electrochemical performance and safety, it is determined that the optimal addition amount is 3 wt%. At this level, there are no significant flames during battery abuse, the triggering temperature for thermal runaway increases by 26.6°C, nd the maximum temperature decreases by 175°C. Moreover, even after 300 cycles at 1/2C, a capacity of 814.5mAh g-1 is retained, with a capacity retention rate of 84.1%. This study provides valuable insights into the mitigation of thermal runaway in high-energy-density power batteries.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141816441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anudeep Mallarapu, I. Çaldichoury, Pierre L'Eplattenier, Nathaniel Sunderlin, S. Santhanagopalan
Considerable advances have been made on battery safety models, but achieving predictive accuracy across a wide range of conditions continues to be challenging. Interactions between dynamically evolving mechanical, electrical and thermal state variables make model prediction difficult during mechanical abuse scenarios. In this study, we develop a physics-based modeling approach which allows for choosing between different mechanical and electrochemical models depending on the required level of analysis. We demonstrate the use of this approach to connect cell-level abuse response to electrode-level and particle-level transport phenomenon. A pseudo-two-dimensional model and a simplified single-particle models are calibrated to electrical-thermal cycling data and applied to mechanically induced short circuit scenario to understand how the choice of electrochemical model affects the model prediction under abuse scenarios. These models are implemented using user defined subroutines on LS-DYNA finite element software and can be coupled with existing automotive crash safety models.
{"title":"Coupled Multiphysics Modeling of Lithium-ion Batteries for Automotive Crashworthiness Applications","authors":"Anudeep Mallarapu, I. Çaldichoury, Pierre L'Eplattenier, Nathaniel Sunderlin, S. Santhanagopalan","doi":"10.1115/1.4066019","DOIUrl":"https://doi.org/10.1115/1.4066019","url":null,"abstract":"\u0000 Considerable advances have been made on battery safety models, but achieving predictive accuracy across a wide range of conditions continues to be challenging. Interactions between dynamically evolving mechanical, electrical and thermal state variables make model prediction difficult during mechanical abuse scenarios. In this study, we develop a physics-based modeling approach which allows for choosing between different mechanical and electrochemical models depending on the required level of analysis. We demonstrate the use of this approach to connect cell-level abuse response to electrode-level and particle-level transport phenomenon. A pseudo-two-dimensional model and a simplified single-particle models are calibrated to electrical-thermal cycling data and applied to mechanically induced short circuit scenario to understand how the choice of electrochemical model affects the model prediction under abuse scenarios. These models are implemented using user defined subroutines on LS-DYNA finite element software and can be coupled with existing automotive crash safety models.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.7,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141821416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yong Li, Yunhao Wu, He Huang, Kai Zhang, Fuqian Yang
Understanding the interaction between mechanical deformation and mass transport, such as diffusion-induced stress, is crucial in the development of advanced battery materials and electrochemical devices. Mathematical modeling and solving the coupling problems have played important roles in advancing the understanding of the interaction between mechanical deformation and mass transport. As the complexity of mathematical modeling continues to increase, numerical methods used to solve the related coupling problems are likely to encounter significant challenges. This work explores the feasibility of designing a neural network specifically for solving diffusion-induced stress in the electrode of lithium-ion battery via deep learning techniques. A loss function is constructed from the spatiotemporal coordinates of sampling points within the solution domain, the overall structure of the system of partial differential equations, boundary conditions, and initial conditions. The distributions of stress and lithium concentration in a hollow-cylindrical nanoelectrode are obtained. The high degree of conformity between the numerical results and those from finite element method is demonstrated.
{"title":"Neural Network-Based Modeling of Diffusion-Induced Stress in a Hollow Cylindrical Nano-Electrode of Lithium-Ion Battery","authors":"Yong Li, Yunhao Wu, He Huang, Kai Zhang, Fuqian Yang","doi":"10.1115/1.4065536","DOIUrl":"https://doi.org/10.1115/1.4065536","url":null,"abstract":"\u0000 Understanding the interaction between mechanical deformation and mass transport, such as diffusion-induced stress, is crucial in the development of advanced battery materials and electrochemical devices. Mathematical modeling and solving the coupling problems have played important roles in advancing the understanding of the interaction between mechanical deformation and mass transport. As the complexity of mathematical modeling continues to increase, numerical methods used to solve the related coupling problems are likely to encounter significant challenges. This work explores the feasibility of designing a neural network specifically for solving diffusion-induced stress in the electrode of lithium-ion battery via deep learning techniques. A loss function is constructed from the spatiotemporal coordinates of sampling points within the solution domain, the overall structure of the system of partial differential equations, boundary conditions, and initial conditions. The distributions of stress and lithium concentration in a hollow-cylindrical nanoelectrode are obtained. The high degree of conformity between the numerical results and those from finite element method is demonstrated.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141122261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ikenna Chris-Okoro, Jacob Som, Sheilah Cherono, Mengxin Liu, Swapnil Nalawade, Xiaochuan Lu, Frank Wise, Shyam Aravamudhan, Dhananjay Kumar
Electrocatalytically active titanium oxynitride (TiNO) thin films were fabricated on commercially available titanium metal plates using a pulsed laser deposition (PLD) method for energy storage applications. The elemental composition and nature of bonding were analyzed using x-ray photoelectron spectroscopy (XPS) to reveal the reacting species and active sites responsible for the enhanced electrochemical performance of the TiNO electrodes. Symmetric supercapacitor devices were fabricated using two TiNO working electrodes separated by an ion-transporting layer to analyze their real-time performance. The galvanostatic charge-discharge studies on the symmetric cell have indicated that TiNO films deposited on the polycrystalline titanium plates at lower temperatures are superior to TiNO films deposited at higher temperatures in terms of storage characteristics. For example, TiNO films deposited at 300°C exhibited the highest specific capacity of 69 mF/cm2 at 0.125 mA/cm2 with an energy density of 7.5 Wh/cm2. The performance of this supercapacitor (300°C TiNO) device is also found to be ∼ 22 % better compared to that of a 500°C TiNO supercapacitor with a capacitance retention ability of 90% after 1000 cycles. The difference in the electrochemical storage and capacitance properties is attributed to the reduced leaching away of oxygen from the TiNO films by the Ti plate at lower deposition temperatures, leading to higher oxygen content in the TiNO films and, consequently, a high redox activity at the electrode/electrolyte interface.
{"title":"Effect of Substrate Temperature on the Electrochemical and Supercapacitance Properties of Pulsed Laser-Deposited Titanium Oxynitride Thin Films","authors":"Ikenna Chris-Okoro, Jacob Som, Sheilah Cherono, Mengxin Liu, Swapnil Nalawade, Xiaochuan Lu, Frank Wise, Shyam Aravamudhan, Dhananjay Kumar","doi":"10.1115/1.4065535","DOIUrl":"https://doi.org/10.1115/1.4065535","url":null,"abstract":"\u0000 Electrocatalytically active titanium oxynitride (TiNO) thin films were fabricated on commercially available titanium metal plates using a pulsed laser deposition (PLD) method for energy storage applications. The elemental composition and nature of bonding were analyzed using x-ray photoelectron spectroscopy (XPS) to reveal the reacting species and active sites responsible for the enhanced electrochemical performance of the TiNO electrodes. Symmetric supercapacitor devices were fabricated using two TiNO working electrodes separated by an ion-transporting layer to analyze their real-time performance. The galvanostatic charge-discharge studies on the symmetric cell have indicated that TiNO films deposited on the polycrystalline titanium plates at lower temperatures are superior to TiNO films deposited at higher temperatures in terms of storage characteristics. For example, TiNO films deposited at 300°C exhibited the highest specific capacity of 69 mF/cm2 at 0.125 mA/cm2 with an energy density of 7.5 Wh/cm2. The performance of this supercapacitor (300°C TiNO) device is also found to be ∼ 22 % better compared to that of a 500°C TiNO supercapacitor with a capacitance retention ability of 90% after 1000 cycles. The difference in the electrochemical storage and capacitance properties is attributed to the reduced leaching away of oxygen from the TiNO films by the Ti plate at lower deposition temperatures, leading to higher oxygen content in the TiNO films and, consequently, a high redox activity at the electrode/electrolyte interface.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141123331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jamie Foster, Young Hahn, Huzefa Patanwala, Victor Oancea, Elham Sahraei
Models that can accurately describe deformation and stress in lithium-ion batteries are required to inform new device designs that can better withstand mechanical fatigue. Developing such models is particularly challenging because (i) there is a need to capture several different materials including, active materials, binders, current collectors and separators, and (ii) the length scales of interest are highly disparate (ranging from a few microns, relevant to active material particles, up to centimeters, relevant to whole devices). In this study we present a continuum mechanical model that resolves individual active material particles of a nickel-manganese-cobalt-oxide cathode, and predicts the mechanical response of the cathode coating as a whole. The model is validated by comparison with experimental tests which mimic industrial-scale electrode calendaring, and then a parametric study is conducted to provide insight into the roles of the material and geometric properties of the electrode's constituents on the cathode's overall behavior.
{"title":"Mechanical deformation in lithium-ion battery electrodes: modelling and experiment","authors":"Jamie Foster, Young Hahn, Huzefa Patanwala, Victor Oancea, Elham Sahraei","doi":"10.1115/1.4065534","DOIUrl":"https://doi.org/10.1115/1.4065534","url":null,"abstract":"\u0000 Models that can accurately describe deformation and stress in lithium-ion batteries are required to inform new device designs that can better withstand mechanical fatigue. Developing such models is particularly challenging because (i) there is a need to capture several different materials including, active materials, binders, current collectors and separators, and (ii) the length scales of interest are highly disparate (ranging from a few microns, relevant to active material particles, up to centimeters, relevant to whole devices). In this study we present a continuum mechanical model that resolves individual active material particles of a nickel-manganese-cobalt-oxide cathode, and predicts the mechanical response of the cathode coating as a whole. The model is validated by comparison with experimental tests which mimic industrial-scale electrode calendaring, and then a parametric study is conducted to provide insight into the roles of the material and geometric properties of the electrode's constituents on the cathode's overall behavior.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141119880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As the fundamental part of battery production, the electrode manufacturing processes have a key impact on the mechanical and electrochemical properties of batteries. A comprehensive study is designed in this paper to reveal the manufacturing effect from the perspective of mechanical properties. Initially, the electrodes samples are prepared after different manufacturing process, i.e., slurry mixing, coating, drying, calendering, slitting, punching, cutting, assembling, electrolyte filling and formation. The effects of these processes on the mechanical response and morphology of electrodes are investigated. The calendering process significantly enhances the strength of both anode and cathode while providing a more uniform distribution of particles on the electrode. Besides, according to literature studies, the slurry mixing process has a critical impact on electrode deformation and failure. Hence, the effects of compaction density ρc and binder content Bc are further discussed to improve the slurry mixing and calendering processes. The active layer will debond from the current collector during cathode failure process as ρc and Bc decreases. This study provides valuable suggestions for optimizing the mechanical response of electrodes under key electrode processes.
作为电池生产的基础部分，电极制造工艺对电池的机械性能和电化学性能有着关键影响。本文设计了一项综合研究，从机械性能的角度揭示制造效应。首先，电极样品经过不同的生产工艺制备而成，这些工艺包括浆料混合、涂覆、干燥、压延、分切、冲压、切割、组装、电解液填充和化成。研究了这些工艺对电极机械响应和形态的影响。压延工艺大大提高了阳极和阴极的强度，同时使电极上的颗粒分布更加均匀。此外，根据文献研究，浆料混合过程对电极变形和失效有重要影响。因此，我们将进一步讨论压实密度 ρc 和粘合剂含量 Bc 的影响，以改进浆料混合和压延工艺。在阴极失效过程中，随着 ρc 和 Bc 的降低，活性层会从集流器上脱落。这项研究为优化关键电极工艺下电极的机械响应提供了宝贵的建议。
{"title":"Optimization of electrode manufacturing processes from the perspective of mechanical properties","authors":"Binqi Li, Jinyang Song, Jianhua Zhou, Jiaying Chen, Jianping Li, Jiang Chen, Lubing Wang, Kai Wu","doi":"10.1115/1.4065380","DOIUrl":"https://doi.org/10.1115/1.4065380","url":null,"abstract":"\u0000 As the fundamental part of battery production, the electrode manufacturing processes have a key impact on the mechanical and electrochemical properties of batteries. A comprehensive study is designed in this paper to reveal the manufacturing effect from the perspective of mechanical properties. Initially, the electrodes samples are prepared after different manufacturing process, i.e., slurry mixing, coating, drying, calendering, slitting, punching, cutting, assembling, electrolyte filling and formation. The effects of these processes on the mechanical response and morphology of electrodes are investigated. The calendering process significantly enhances the strength of both anode and cathode while providing a more uniform distribution of particles on the electrode. Besides, according to literature studies, the slurry mixing process has a critical impact on electrode deformation and failure. Hence, the effects of compaction density ρc and binder content Bc are further discussed to improve the slurry mixing and calendering processes. The active layer will debond from the current collector during cathode failure process as ρc and Bc decreases. This study provides valuable suggestions for optimizing the mechanical response of electrodes under key electrode processes.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140670720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yong-Chun Tong, Qing-Yun Wang, Yu-Jie Hu, Zhi-Juan Shi, Ke Zhang
The O-H/C-H scission of methanol on Pt clusters is a crucial step in direct methanol fuel cells (DMFCs) applications. The first dehydrogenation process of methanol on Ptnq clusters (n=5, 13, 19; q=0, +1, −1) in various charge states is studied. Our findings indicate that methanol adsorbs more easily on cationic Ptn+ than on neutral Ptn or anionic Ptn−. However, the adsorption capacity of methanol on Ptnq gradually decreases with increasing cluster size, especially for CH3OH on Ptn+, which decreases significantly (from −57.61 to −16.41 kcal/mol). Compared with Ptn and Ptn+, the energy barrier of O-H/C-H bond cleavage is significantly reduced by injecting an electron into Ptn to form Ptn−, and the activity of catalyst is improved. However, the energy barrier of O-H/C-H cleavage increases gradually with cluster size, leading to a decrease in catalytic activity. The effect of charge weakens as cluster size increases, and small clusters with injected electrons exhibit better catalytic activity.
{"title":"The size and charge effect of Pt cluster on the electrocatalytic activity towards the first step of dehydrogenation of methanol","authors":"Yong-Chun Tong, Qing-Yun Wang, Yu-Jie Hu, Zhi-Juan Shi, Ke Zhang","doi":"10.1115/1.4065275","DOIUrl":"https://doi.org/10.1115/1.4065275","url":null,"abstract":"\u0000 The O-H/C-H scission of methanol on Pt clusters is a crucial step in direct methanol fuel cells (DMFCs) applications. The first dehydrogenation process of methanol on Ptnq clusters (n=5, 13, 19; q=0, +1, −1) in various charge states is studied. Our findings indicate that methanol adsorbs more easily on cationic Ptn+ than on neutral Ptn or anionic Ptn−. However, the adsorption capacity of methanol on Ptnq gradually decreases with increasing cluster size, especially for CH3OH on Ptn+, which decreases significantly (from −57.61 to −16.41 kcal/mol). Compared with Ptn and Ptn+, the energy barrier of O-H/C-H bond cleavage is significantly reduced by injecting an electron into Ptn to form Ptn−, and the activity of catalyst is improved. However, the energy barrier of O-H/C-H cleavage increases gradually with cluster size, leading to a decrease in catalytic activity. The effect of charge weakens as cluster size increases, and small clusters with injected electrons exhibit better catalytic activity.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140740475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Due to the advantages of ultra high power density, long cyclic life and desirable safety, ultra-high-rate LiFePO4/graphite batteries(U-LIBs) are used as the energy storage system for electromagnetic launcher. However, the short calendar life of U-LIB limits its further application in the field of electromagnetic launch. In this study, the calendar life of commercial U-LIB is improved through the optimization design of anode materials and electrolyte. The calendar life is successfully improved without affecting the battery performances by appropriately increasing the particle size of graphite in the anode and properly reducing the proportion of dimethyl carbonate (DMC) which has low stability in the electrolyte. The average particle size of graphite is increased from 5 µm to 8 µm with a compaction density of 1.3 g cm−3 as the best option. The electrolyte formulation is optimized from 30% ethylene carbonate (EC), 60% DMC, 10% ethyl methyl carbonate (EMC) to 30% EC, 50% DMC, 20% EMC. After comprehensive optimization, the calendar life of commercial U-LIB was significant improved at different temperature and state of charge(SOC). For example, the one-month-storage capacity retention of U-LIB increased from 96.9% to 98% under the temperature of 45°C at 50%SOC (meaning 35.5% decrease on capacity loss), and increased from 98.2% to 98.8% under the temperature of 25°C at 100%SOC (33.3% decrease on capacity loss).
{"title":"Calendar life enhancement of commercial ultra-high-rate LiFePO4/graphite batteries for electromagnetic launch","authors":"Xinlin Long, Lang Liu, Ziqing Zeng","doi":"10.1115/1.4065279","DOIUrl":"https://doi.org/10.1115/1.4065279","url":null,"abstract":"\u0000 Due to the advantages of ultra high power density, long cyclic life and desirable safety, ultra-high-rate LiFePO4/graphite batteries(U-LIBs) are used as the energy storage system for electromagnetic launcher. However, the short calendar life of U-LIB limits its further application in the field of electromagnetic launch. In this study, the calendar life of commercial U-LIB is improved through the optimization design of anode materials and electrolyte. The calendar life is successfully improved without affecting the battery performances by appropriately increasing the particle size of graphite in the anode and properly reducing the proportion of dimethyl carbonate (DMC) which has low stability in the electrolyte. The average particle size of graphite is increased from 5 µm to 8 µm with a compaction density of 1.3 g cm−3 as the best option. The electrolyte formulation is optimized from 30% ethylene carbonate (EC), 60% DMC, 10% ethyl methyl carbonate (EMC) to 30% EC, 50% DMC, 20% EMC. After comprehensive optimization, the calendar life of commercial U-LIB was significant improved at different temperature and state of charge(SOC). For example, the one-month-storage capacity retention of U-LIB increased from 96.9% to 98% under the temperature of 45°C at 50%SOC (meaning 35.5% decrease on capacity loss), and increased from 98.2% to 98.8% under the temperature of 25°C at 100%SOC (33.3% decrease on capacity loss).","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140739262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Baohe Yuan, Zheng An, Heng Qi, Jianming Chen, Qi Xu
With the development of lithium-ion batteries, high capacity and high cycle stability have been the two main goals being pursued. Recent studies have shown that ZrV2O7 does not perform well in energy storage due to its low electrical conductivity and poor cycling stability. Elemental doping has proven to be an effective strategy for improving electrochemical performance. In this paper, we prepared Zr0.1Fe0.9V1.1Mo0.9O7(ZFVMO) and Zr0.1Fe0.9V1.1Mo0.9O7@C (ZFVMO@C) materials using a simple solid-phase sintering method and a fast microwave sintering method. Double ionic heterovalent substitution of Zr4+/V5+ in ZrV2O7 using Fe3+/Mo6+, Fe3+/Mo6+ gives it near-zero thermal expansion characteristics and excellent conductive properties. In electrochemical tests, the first discharge capacities of ZFVMO and ZFVMO@C are 2261 mA h g−1 and 727 mA h g−1 respectively, and the batteries were finally stabilized for 475 and 500 cycles. Compared to ZrV2O7, the electrochemical properties of ZFVMO are greatly improved.
随着锂离子电池的发展，高容量和高循环稳定性一直是人们追求的两大目标。最近的研究表明，ZrV2O7 由于导电率低和循环稳定性差，在储能方面表现不佳。事实证明，元素掺杂是提高电化学性能的有效策略。本文采用简单的固相烧结法和快速微波烧结法制备了 Zr0.1Fe0.9V1.1Mo0.9O7（ZFVMO）和 Zr0.1Fe0.9V1.1Mo0.9O7@C（ZFVMO@C）材料。利用 Fe3+/Mo6+、Fe3+/Mo6+ 对 ZrV2O7 中的 Zr4+/V5+进行双离子异价置换，使其具有接近零的热膨胀特性和优异的导电性能。在电化学测试中，ZFVMO 和 ZFVMO@C 的首次放电容量分别为 2261 mA h g-1 和 727 mA h g-1，电池最终在 475 次和 500 次循环中保持稳定。与 ZrV2O7 相比，ZFVMO 的电化学性能有了很大提高。
{"title":"Zr0.1Fe0.9V1.1Mo0.9O7 as cathode for LIB","authors":"Baohe Yuan, Zheng An, Heng Qi, Jianming Chen, Qi Xu","doi":"10.1115/1.4065248","DOIUrl":"https://doi.org/10.1115/1.4065248","url":null,"abstract":"\u0000 With the development of lithium-ion batteries, high capacity and high cycle stability have been the two main goals being pursued. Recent studies have shown that ZrV2O7 does not perform well in energy storage due to its low electrical conductivity and poor cycling stability. Elemental doping has proven to be an effective strategy for improving electrochemical performance. In this paper, we prepared Zr0.1Fe0.9V1.1Mo0.9O7(ZFVMO) and Zr0.1Fe0.9V1.1Mo0.9O7@C (ZFVMO@C) materials using a simple solid-phase sintering method and a fast microwave sintering method. Double ionic heterovalent substitution of Zr4+/V5+ in ZrV2O7 using Fe3+/Mo6+, Fe3+/Mo6+ gives it near-zero thermal expansion characteristics and excellent conductive properties. In electrochemical tests, the first discharge capacities of ZFVMO and ZFVMO@C are 2261 mA h g−1 and 727 mA h g−1 respectively, and the batteries were finally stabilized for 475 and 500 cycles. Compared to ZrV2O7, the electrochemical properties of ZFVMO are greatly improved.","PeriodicalId":15579,"journal":{"name":"Journal of Electrochemical Energy Conversion and Storage","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140753072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：