Research

Jump to: Review

15 pages, 15642 KiB

Open AccessArticle

Analytical Model of Critical Ventilation Flow Rate for Accidental Hydrogen Leakage in a Confined Space

by Xuxu Sun, Jiale Yang, Jun Wang, Xianfeng Chen and Jihao Shi

Energies 2023, 16(19), 6864; https://doi.org/10.3390/en16196864 - 28 Sep 2023

Viewed by 846

The determination of the critical ventilation flow rate is significant for risk control and standard development during accidental hydrogen leakage in a confined space with hydrogen-related equipment. This paper presents an analytical model for calculating the critical ventilation flow rate through the quantification [...] Read more.

The determination of the critical ventilation flow rate is significant for risk control and standard development during accidental hydrogen leakage in a confined space with hydrogen-related equipment. This paper presents an analytical model for calculating the critical ventilation flow rate through the quantification and constraint solution of the ventilation effect and ventilation cost. The experimental method was used to investigate the effects of nozzle diameter and stagnation pressure on the diffusion and ventilation of horizontal hydrogen leakage in a cuboid chamber. Ventilations from 30 to 180 m³/h were carried out through the rectangular vent. It was shown that the peak concentration of the measuring point was positively correlated with the stagnation pressure and the nozzle diameter. The experimental data were used to verify the analytical model by calculating the effective ventilation time. This study demonstrates that the critical ventilation flow rate can be increased significantly at higher stagnation pressures and larger nozzle diameters. Furthermore, the discrepancy of critical ventilation flow rates under different nozzle diameters will be enhanced with the increase of stagnation pressure. For a stagnation pressure of 0.4 MPa, the critical ventilation flow rate under a 4 mm nozzle even increased by 52% relative to the 2 mm nozzle. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

14 pages, 3419 KiB

Open AccessArticle

Characteristics of Explosion Hazards in Methane–Air Mixtures Diluted by Hydrogen

by Jiajia Liu, Danyang Yu, Ping Li, Xuxu Sun and Xianfeng Chen

Energies 2023, 16(18), 6416; https://doi.org/10.3390/en16186416 - 05 Sep 2023

Viewed by 826

Abstract

The combustion efficiency of methane can be effectively enhanced with the occurrence of hydrogen. However, the combustion characteristic of premixed methane/hydrogen/air is not fully understood. In this study, the effect of the amount of hydrogen addition on the explosion risk of premixed CH [...] Read more.

The combustion efficiency of methane can be effectively enhanced with the occurrence of hydrogen. However, the combustion characteristic of premixed methane/hydrogen/air is not fully understood. In this study, the effect of the amount of hydrogen addition on the explosion risk of premixed CH₄/air combustion was fully investigated through experiments and simulations. The explosion overpressure of premixed CH₄/air combustion with various hydrogen additions was measured in a standard 20 L spherical closed vessel. Meanwhile, the microscopic flame structures for the same cases were simulated using 2022 Chemkin-Pro software. The results showed that hydrogen could increase the explosion risks of premixed CH₄/air combustion. The rate of key elementary reactions R38: H + O₂ <=> O + OH and R84: OH + H₂ <=> H + H₂O in the system could be accelerated by hydrogen. The peak explosion overpressure in the closed chamber is boosted and the arrival time of peak overpressure rise rate is shortened, which raises the danger. Especially under lean and rich combustion conditions, hydrogen could potentially lead to more dangerous situations. With the increase in hydrogen concentration, the reaction rate of key elementary reactions accelerates faster, the peak explosion overpressure increases more, and the peak overpressure rise rate arrives earlier. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

14 pages, 3425 KiB

Open AccessArticle

Online Prediction of Electric Vehicle Battery Failure Using LSTM Network

by Xuemei Li, Hao Chang, Ruichao Wei, Shenshi Huang, Shaozhang Chen, Zhiwei He and Dongxu Ouyang

Energies 2023, 16(12), 4733; https://doi.org/10.3390/en16124733 - 15 Jun 2023

Cited by 3 | Viewed by 1116

Abstract

The electric vehicle industry is developing rapidly as part of the global energy structure transformation, which has increased the importance of overcoming power battery safety issues. In this paper, first, we study the relationship between different types of vehicle faults and battery data [...] Read more.

The electric vehicle industry is developing rapidly as part of the global energy structure transformation, which has increased the importance of overcoming power battery safety issues. In this paper, first, we study the relationship between different types of vehicle faults and battery data based on the actual vehicle operation data in the big data supervisory platform of new energy vehicles. Second, we propose a method to realize the online prediction of electric vehicle battery faults, based on a Long Short-Term Memory (LSTM). Third, we carry out prediction research for two kinds of faults: low State of Charge (SOC) alarm and insulation alarm. Last, we show via experimental results that the model based on the LSTM network can effectively predict battery faults with an accuracy of more than 85%. Through this research, it is possible to complete online pre-processing of vehicle operation data and fault prediction of power batteries, improve vehicle monitoring capabilities and ensure the safety of electric vehicle use. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

16 pages, 8158 KiB

Open AccessArticle

Study on Surface Configurations and Force Transfer Mechanism of Dual-Wedge Shaped Slips for Liner Hanger

by Feng Han, Hua Han, Pengrui Zhong, Yong Zou, Jiqiang Huang and Long Xue

Energies 2023, 16(7), 3177; https://doi.org/10.3390/en16073177 - 31 Mar 2023

Cited by 1 | Viewed by 1309

Abstract

The penetration force and depth of the slip teeth are important factors influencing the hanging capacity of liner hanger, which can lead to failure of well cementation. In this study, a method to calculate the penetration force of dual-wedge slip teeth was presented [...] Read more.

The penetration force and depth of the slip teeth are important factors influencing the hanging capacity of liner hanger, which can lead to failure of well cementation. In this study, a method to calculate the penetration force of dual-wedge slip teeth was presented by considering the surface configuration and the force transfer mechanism of dual-wedge slip in three dimensions. The interaction between dual-wedge slips and casing was simulated using ABAQUS 6.14 software, and the contact force (penetration force) was obtained. Experimental research was carried out to verify the correction of calculation and simulation. The strain of casing was obtained after the dual-wedge slips set under axial loads. The experimental results, theoretical prediction, and the numerical simulation are in good agreement. The effects of geometrical parameters on force transfer characteristics were discussed, which shows that the penetration force of dual-wedge slips increases with increase in the liner weight and Eulerian angle γ, and it decreases with the increase in Eulerian angle α and friction coefficient. The geometric parameters of the dual-wedge slip can be designed to obtain an optimal penetration force, and ensure that the slip teeth penetrate into the inner wall of casing without damage to the casing. The penetration force can be obtained by optimizing the parameters related to geometry of dual-wedge slips. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

17 pages, 4331 KiB

Open AccessArticle

Investigation on the Properties of Flame-Retardant Phase Change Material and Its Application in Battery Thermal Management

by Yilin Cui, Yin Chen, Luyao Zhao, Fang Zhu, Lixia Li, Qinghong Kong and Mingyi Chen

Energies 2023, 16(1), 521; https://doi.org/10.3390/en16010521 - 03 Jan 2023

Cited by 6 | Viewed by 1758

Abstract

The thermal safety problem of lithium-ion batteries (LIB) in use requires an excellent thermal management system to preserve it. In the paper, an expansion flame-retardant composed of APP and CFA and kaolinite is used to enhance the flame-retardant property of phase change materials [...] Read more.

The thermal safety problem of lithium-ion batteries (LIB) in use requires an excellent thermal management system to preserve it. In the paper, an expansion flame-retardant composed of APP and CFA and kaolinite is used to enhance the flame-retardant property of phase change materials (PCM). The performances of PCM and their property in the thermal management of LIB were studied. The results indicate that the kaolinite can improve the long-term thermostability of PCM. The addition of flame retardant can make the flame-retardant property of PCM reach V0 level. The synergistic action of expansion flame-retardant and kaolinite can increase the residual carbon and enhance the thermal reliability of flame-retardant PCM (RPCM). The RPCM has an obvious cooling effect on the surface temperature of the battery. The RPCM can reduce the maximum temperature of the cell to 37.4 °C at 3 C, which is 12 °C lower than pure PA. The peak temperature of the battery pack at 3 C is also reduced to 50.28 °C by the flame-retardant PCM, and the temperature difference is kept within 5 °C. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

16 pages, 4755 KiB

Open AccessArticle

Numerical Simulation of the Combination of Novel Spiral Fin and Phase Change Material for Cylindrical Lithium-Ion Batteries in Passive Thermal Management

by Jiahao Liu, Qingwen Ma and Xianbin Li

Energies 2022, 15(23), 8847; https://doi.org/10.3390/en15238847 - 23 Nov 2022

Cited by 5 | Viewed by 2173

Abstract

This paper uses ANSYS Fluent to simulate the heat dissipation of a phase change material (PCM)-based cooling system combined with novel spiral fins for a single battery cell. Compared with a circular fin, a spiral fin with the same contact length can reduce [...] Read more.

This paper uses ANSYS Fluent to simulate the heat dissipation of a phase change material (PCM)-based cooling system combined with novel spiral fins for a single battery cell. Compared with a circular fin, a spiral fin with the same contact length can reduce the battery temperature by 0.72 °C, and has a superior temperature uniformity. For the PCM-based system with spiral fins, increasing the spiral width from 2 mm to 8 mm can reduce the battery temperature from 41.27 °C to 39.9 °C. As the number of spiral turns increases from two to eight, the maximum temperature rise of the battery shows a downward trend, and six turns can effectively satisfy the heat dissipation requirements of the battery. With respect to the effect of ambient temperature on the cooling performance, the system with a PCM-spiral fin still exhibits optimal cooling effectiveness compared with the pure PCM and PCM-circular systems. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

14 pages, 4249 KiB

Open AccessArticle

Theoretical and Experimental Investigation of Explosion Characteristics of Hydrogen Explosion in a Closed Vessel

by Huadao Xing, Runze Yu, Guangan Xu, Xiaodong Li, Yanyu Qiu, Derong Wang, Bin Li and Lifeng Xie

Energies 2022, 15(22), 8630; https://doi.org/10.3390/en15228630 - 17 Nov 2022

Cited by 4 | Viewed by 1507

Abstract

A simplified model that calculates the deflagration pressure–time curves of a hydrogen explosion was proposed. The deflagration parameters (pressure peak, duration, deflagration index, and impulse) of hydrogen–air mixtures with different hydrogen concentrations were experimentally investigated. The results show that the pressure curves calculated [...] Read more.

A simplified model that calculates the deflagration pressure–time curves of a hydrogen explosion was proposed. The deflagration parameters (pressure peak, duration, deflagration index, and impulse) of hydrogen–air mixtures with different hydrogen concentrations were experimentally investigated. The results show that the pressure curves calculated by the model are consistent with experimental data pertaining to a methane and hydrogen explosion. By comparison, the pressure peak and deflagration index are found to be influenced by the aspect ratio and surface area of vessels. The impulse and explosion times at fuel-lean hydrogen concentrations are greater than those at fuel-rich concentrations. When the hydrogen concentration is between 34 vol.% and 18 vol.%, the greatest explosion damage effect is formed by both the overpressure and the impulse, which should be considered for hydrogen explosion safety design in industrial production. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

Review

Jump to: Research

21 pages, 3847 KiB

Open AccessReview

Recent Advances in Ball-Milling-Based Silicon Anodes for Lithium-Ion Batteries

by Han Yang, Shiyu Lin, Alex Cheng, Fangbo He, Zhoulu Wang, Yutong Wu, Yi Zhang and Xiang Liu

Energies 2023, 16(7), 3099; https://doi.org/10.3390/en16073099 - 29 Mar 2023

Cited by 4 | Viewed by 3278

Abstract

Having a high theoretical capacity density of 4200 mAh g⁻¹, silicon has been highlighted as one of the most promising anode materials for lithium-ion batteries. Countless silicon-based materials have been proposed and reported in research articles, mostly synthesized using bottom-up methods. [...] Read more.

Having a high theoretical capacity density of 4200 mAh g⁻¹, silicon has been highlighted as one of the most promising anode materials for lithium-ion batteries. Countless silicon-based materials have been proposed and reported in research articles, mostly synthesized using bottom-up methods. While the infamous volume expansion issue can be settled with the bottom-up processes, the complicated protocols and high cost leave a non-neglectable gap between laboratory-scale and mass production. The top-down ball-milling method is still favored by industrial suppliers because of its simplicity and cost-effectiveness, even with compromised electrochemical performances. This paper reviews the latest development of ball-milling-based silicon anode materials. Although the ball-milling process seems straightforward, the procedures and parameters influencing the product have hardly been discussed in research papers compared to the bottom-up ones. This paper reviews recent advances in ball-milling-based silicon anode materials, provides a material comparison, and discusses how ball milling can provide lithium-ion batteries with greater possibilities at a larger scale. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

35 pages, 4489 KiB

Open AccessReview

Early Warning Method and Fire Extinguishing Technology of Lithium-Ion Battery Thermal Runaway: A Review

by Kuo Wang, Dongxu Ouyang, Xinming Qian, Shuai Yuan, Chongye Chang, Jianqi Zhang and Yifan Liu

Energies 2023, 16(7), 2960; https://doi.org/10.3390/en16072960 - 23 Mar 2023

Cited by 8 | Viewed by 4734

Abstract

Lithium-ion batteries (LIBs) are widely used in electrochemical energy storage and in other fields. However, LIBs are prone to thermal runaway (TR) under abusive conditions, which may lead to fires and even explosion accidents. Given the severity of TR hazards for LIBs, early [...] Read more.

Lithium-ion batteries (LIBs) are widely used in electrochemical energy storage and in other fields. However, LIBs are prone to thermal runaway (TR) under abusive conditions, which may lead to fires and even explosion accidents. Given the severity of TR hazards for LIBs, early warning and fire extinguishing technologies for battery TR are comprehensively reviewed in this paper. First, the TR reaction mechanism and hazards of LIBs are discussed. Second, the TR early warning and monitoring methods of LIBs are summarized in five aspects consisting of acoustic, heat, force, electricity, and gas. In addition, to reduce the fire and explosion hazards caused by the TR of LIBs, the highly efficient extinguishing agents for LIBs are summarized. Finally, the early warning technology and fire extinguishing agent are proposed, which provides a reference for the hazard prevention and control of energy storage systems. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

16 pages, 22033 KiB

Open AccessReview

Electrochemical Impedance Spectroscopy: A New Chapter in the Fast and Accurate Estimation of the State of Health for Lithium-Ion Batteries

by Ming Zhang, Yanshuo Liu, Dezhi Li, Xiaoli Cui, Licheng Wang, Liwei Li and Kai Wang

Energies 2023, 16(4), 1599; https://doi.org/10.3390/en16041599 - 05 Feb 2023

Cited by 91 | Viewed by 8376

Abstract

Lithium-ion batteries stand out from other clean energy sources because of their high energy density and small size. With the increasing application scope and scale of lithium-ion batteries, real-time and accurate monitoring of its state of health plays an important role in ensuring [...] Read more.

Lithium-ion batteries stand out from other clean energy sources because of their high energy density and small size. With the increasing application scope and scale of lithium-ion batteries, real-time and accurate monitoring of its state of health plays an important role in ensuring the healthy and stable operation of an energy storage system. Due to the interaction of various aging reactions in the aging process of lithium-ion batteries, the capacity attenuation shows no regularity. However, the traditional monitoring method is mainly based on voltage and current, which cannot reflect the internal mechanism, so the accuracy is greatly reduced. Recently, with the development of electrochemical impedance spectroscopy, it has been possible to estimate the state of health quickly and accurately online. Electrochemical impedance spectroscopy can measure battery impedance in a wide frequency range, so it can reflect the internal aging state of lithium-ion batteries. In this paper, the latest impedance spectroscopy measurement technology and electrochemical impedance spectroscopy based on lithium-ion battery health state estimation technology are summarized, along with the advantages and disadvantages of the summary and prospects. This fills the gap in this aspect and is conducive to the further development of this technology. Full article

(This article belongs to the Special Issue Development of New Energy Materials/Devices and Their Safety)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Development of New Energy Materials/Devices and Their Safety

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (10 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI