Battery Characteristics Research Articles

Analysis of Pressure Characteristics of Ultra-High Specific Energy Lithium Metal Battery for Flying Electric Vehicles

The lithium metal battery is likely to become the main power source for the future development of flying electric vehicles for its ultra-high theoretical specific capacity. In an attempt to study macroscopic battery performance and microscopic lithium deposition under different pressure conditions, we first conduct a pressure cycling test proving that amplifying the initial preload can delay the battery failure stage, and the scanning electron microscope (SEM) shows that the pressure is effective in improving the electrode’s surface structure. Secondly, we analyze how differing pressure conditions affect the topography of lithium deposits by coupling the nonlinear phase-field model with the force model. The results show that the gradual increase in the external pressure is accompanied by a drop in the length of the dendrite and the migration curvature in the diaphragm, and the deposition morphology is gradually geared towards smooth and thick development, which can significantly reduce the specific surface area of lithium dendrite. However, as cyclic charging and discharging continue, the decrease in the electrolyte diffusion coefficient results in higher internal stress inside the battery, and thus the external pressure must be increased so as to achieve marked inhibitory effects on the growth of the lithium dendrite.

Study on fire characteristics of lithium battery of new energy vehicles in a tunnel

In order to explore fire safety of lithium battery of new energy vehicles in a tunnel, a numerical calculation model for lithium battery of new energy vehicle was established. This paper used eight heat release rate (HRR) for lithium battery of new energy vehicle calculation models, and conducted a series of simulation calculations to analyze and compare the fire development characteristics of fuel vehicles and new energy vehicles with different HRR in a tunnel. This paper investigated temperature distribution below the ceiling and smoke diffusion in a tunnel, as well as the distribution of CO2 and CO concentrations, to explore the spread of lithium battery of new energy vehicle fires in a tunnel. Then, the accuracy of the numerical simulation was verified through comparison with existing examples. The results showed that there is a correlation between the temperature distribution below the ceiling in a tunnel and the HRR of lithium battery of new energy vehicle fires, with higher HRR and higher temperature below the ceiling in a tunnel. In addition, the heat release of fuel vehicles in a tunnel is lower than that of lithium battery of new energy vehicles. The analysis of the ceiling temperature of new energy vehicles in tunnels after a fire showed that for different HRR, the temperature below the ceiling increases with the increase of HRR. In tunnel fires, lithium battery of new energy vehicles generate higher temperature, smoke, and CO emission concentrations than fuel vehicles. Therefore, the risk of fire for lithium battery of new energy vehicles in tunnels is higher than that of fuel vehicles, and their fire safety needs to be paid more attention.

Towards a State of Health Definition of Lithium Batteries through Electrochemical Impedance Spectroscopy

In the era of Industry 4.0, achieving optimization in production and minimizing environmental impact has become vital. Energy management, particularly in the context of smart grids, plays a crucial role in ensuring sustainability and efficiency. Lithium-ion batteries have emerged as a leading technology for energy storage due to their versatility and performances. However, accurately assessing their State of Health (SOH) is essential for maintaining grid reliability. While discharge capacity and internal resistance (IR) are commonly used SOH indicators, battery impedance also offers valuable insights into aging degradation. This article explores the use of Electrochemical Impedance Spectroscopy (EIS) to define the SOH of lithium batteries. By analyzing impedance spectra at different frequencies, a comprehensive understanding of battery degradation is obtained. A life cycle analysis is conducted on cylindrical Li–Mn batteries under various discharge conditions, utilizing EIS measurements and an Equivalent Circuit Model (ECM). This study highlights the differential effects of aging on battery characteristics, emphasizing the variations at different life stages and the behavior changes on each region of the impedance spectrum. Furthermore, it demonstrates the efficacy of EIS and the advantages of this technique compared to the solely IR measurements used in tracking SOH over time. This research contributes to advancing the understanding of lithium battery degradation and underscores the importance of EIS in defining their State of Health for Smart Grids applications.

The suppression of thermal propagation using spray cooling with R410A in overheated lithium battery pack

Currently, the thermal safety control of lithium-ion batteries for electric vehicles has emerged as a prominent research focus in both academia and industry. During the transition from overheating to the initial stage of thermal runaway, lithium batteries undergo an overheating decomposition reaction, which presents an opportunity for proactive prevention of thermal runaway. In this context, this study proposes a spray cooling method and performs numerical simulations to investigate the impact of spray cooling on suppressing overheating propagation in battery packs. Specifically, we examine the suppressor effect of spray cooling on propagating overheating within the battery pack. The cooling effect of R410A spray was investigated at three typical positions prone to overheating. We analyzed changes in thermal behavior characteristics of individual batteries within the pack and evaluated its inhibitory effect on propagating of overheating. The spray strategy is also improved and optimized by increasing the number of spray nozzles and spraying in advance. The results demonstrate that the implementation of the spray cooling method in this study effectively mitigates the average temperature of the overheated battery, thereby preventing the overheating decomposition reaction. Simultaneously, the spray cooling effectively suppresses the heat propagation of excessively heated batteries within the battery pack, thereby preventing and delaying the onset of thermal runaway in the battery pack.

Enhanced electrochemical performance of cerium-based metal organic frameworks derived from pyridine-2,4,6-tricarboxylic acid for energy storage devices

Modern era demands development of hybrid supercapacitor amalgamating characteristics of battery and supercapacitor is a single unit. Various contender electrode materials have been used so far, however, metal organic frameworks, having rich porosity and distinctive electrochemical properties can be integrated in energy storage devices to improve electrochemical performance. Herein, we have synthesized Ce-PTA-MOF from pyridine-2,4,6-tricarboxylic acid which was structurally as well as electrochemically characterized. Effects of different concentrations of KOH electrolyte on electrochemical properties of Ce-PTA-MOF electrode has been investigated using three electrodes assembly and practical applications of hybrid supercapacitor device has also been explored by fabricating it with activated carbon. The stability and capacitive-diffusive contributions of the hybrid supercapacitor has been analyzed by theoretical approach. The specific capacity, maximum energy density and power density were calculated as 115 C/g, 26.75 Wh/kg and 5760 W/kg respectively which showed efficiency of 99.2 % even after 5000 GCD cycles. High energy density and power density with extraordinary stability make Ce-PTA-MOF electrode a promising candidate for futuristic hybrid supercapacitor devices.

Simulation of Dispersion and Explosion Characteristics of LiFePO4 Lithium-Ion Battery Thermal Runaway Gases.

In recent years, as the installed scale of battery energy storage systems (BESS) continues to expand, energy storage system safety incidents have been a fast-growing trend, sparking widespread concern from all walks of life. During the thermal runaway (TR) process of lithium-ion batteries, a large amount of combustible gas is released. In this paper, the 105 Ah lithium iron phosphate battery TR test was conducted, and the flammable gas components released from the battery TR were detected. The simulation tests of the diffusion and explosion characteristics of lithium iron phosphate battery's (LFP) TR gases with different numbers and positions in the BESS were carried out using FLACS simulation software. It was found that the more batteries TR simultaneously, the shorter the time for the combustible gas concentration in the energy storage cabin to reach the explosion limit. When 48 batteries were in TR simultaneously in the energy storage cabin, the shortest time was 9.8 s, and the further the location of the fire is from the hatch, the largest explosion overpressure is generated to the hatch, up to 583 kPa. When the gas generated by the TR of 48 batteries explodes, the maximum explosion overpressure at 5 m outside the energy storage cabin hatch is more significant than 40 kPa, which will cause serious injury to humans. The causes of TR of batteries in prefabricated chambers are complex, and the location and amount of thermal runaway of batteries as well as the diffusion of combustible fumes can have different effects on the external environment. The research results can provide support for the safety design of BESS.

Strategy of Flywheel–Battery Hybrid Energy Storage Based on Optimized Variational Mode Decomposition for Wind Power Suppression

The fluctuation and intermittency of wind power generation seriously affect the stability and security of power grids. Aiming at smoothing wind power fluctuations, this paper proposes a flywheel–battery hybrid energy storage system (HESS) based on optimal variational mode decomposition (VMD). Firstly, the grid-connected power and charging–discharging power of the HESS are determined based on the sliding average algorithm. Secondly, the VMD algorithm, optimized using long short-term memory (LSTM), is used to decompose the hybrid energy storage power (HESP) into a series of sub-modes with frequencies from low to high. Then, the state of charge of the battery energy storage system and the speed of the flywheel energy storage system are monitored in real time, and the primary power of the HESS is modified according to the rules formulated by fuzzy control. Finally, through a simulation example, it is concluded that the method meets the requirements of smoothing wind power fluctuations and gives full play to the characteristics of energy storage battery and flywheel energy storage to ensure the stable operation of the energy storage system. The method presented in this paper can provide a reference for HESP configuration and control operation strategy formulation.

Numerical study on the critical characteristics of internal short-circuit hot spot in lithium-ion batteries

High current density resulting from internal short circuit (ISC) in lithium-ion batteries leads to rapid local temperature rise, forming a hot spot. This study quantitatively characterized the critical properties of ISC hot spot in batteries. ISC hot spot in batteries exhibit two different evolution patterns. When the short circuit resistance approaches the internal resistance of the battery, the hot spot temperature reaches its peak at 1165 K. The thermal runaway characteristics of batteries vary depending on the short circuit resistance, with the hot spot growing and spreading rapidly when the resistance value is 30 mΩ. In addition, a modeling study was conducted to examine the critical characteristics of short circuit resistance. At a hot spot radius of 2 mm, the critical resistance was determined to be 281 mΩ, accompanied by a critical hot spot temperature of 562 K. Under subcritical conditions, the SEI film decomposes completely, while the electrolyte undergoes minimal decomposition. Interestingly, it was observed that the critical resistance and critical hot spot temperature decrease as the hot spot radius increases. Finally, the study quantified the effects of hot spot thermal conductivity, convective heat transfer coefficient, and hot spot position on the critical threshold of hot spots. These findings provide valuable references for the design of batteries with high critical thresholds.

Electrochemical Characteristics of Lithium-Air Secondary Battery Using Amide-Based Ionic Liquids

Electrochemical Characteristics of Lithium-Air Secondary Battery Using Amide-Based Ionic Liquids

Effects of capacity on the thermal runaway and gas venting behaviors of large-format lithium iron phosphate batteries induced by overcharge

Large-capacity lithium iron phosphate (LFP) batteries are widely used in electric bicycles. However, while crucial, thermal runaway (TR) behaviors under overcharge conditions have rarely been studied, leading to frequent fire accidents. This paper investigates the overcharge behavior and TR characteristics of four LFP batteries with the same components and materials but varying capacities (86, 100, 120, and 140 Ah). Overcharge tests were conducted in a customized apparatus, and the surface temperature, mass loss, and gas venting phenomenon were recorded. The results revealed that under the same overcharge conditions, the TR early warning temperature can differ considerably with respect to battery capacity, highlighting the importance of selecting the appropriate early warning temperature in real-time temperature monitoring based on the capacity of the LFP battery. Three characteristic times were used to describe the thermal behavior of the batteries, namely, the time to reach the voltage plateau (tPV), the time when the safety valve opens (tSV), and the start time of TR (tTR). Analysis of critical heat accumulation indicated that the 86 Ah LFP battery has the lowest tolerance to overcharge and, thus, the highest TR risk. However, after TR, the 86 Ah LFP battery exhibited the smallest maximum temperature (Tmax), maximum temperature increase rate (Rmax), maximum total mass loss, and maximum mass loss rate (Mmax) among all the batteries, suggesting the least TR hazard. Consequently, a safety evaluation and scoring system using these six parameters was established considering the overcharge behavior and TR characteristics of LFP batteries. The results indicated that the TR risk ranking of LFP batteries with different capacities was 86 Ah LFP > 100 Ah LFP > 140 Ah LFP > 120 Ah LFP, while the TR hazard ranking was 140 Ah LFP > 120 Ah LFP > 100 Ah LFP > 86 Ah LFP. This comparative study of LFP batteries with varying capacities enhances our understanding of their overcharge behavior and TR characteristics, and a safety evaluation and scoring system can also be used for risk and hazard assessments of other types of batteries.

Development of electroforming technology for flexible metal substrates for high-efficiency double-sided electronic devices

In this study, we investigate a novel material that surpasses conventional concepts used for substrate materials in flexible electronic devices. Unlike traditional materials, this novel material can replace polymers with a metallic substance. This substance is capable of supporting electronic devices on both sides. Our development focuses on a metallic substrate material based on Fe-Ni. This material allows for the implementation of secondary batteries on its extremely flat opposite side through the electroforming method. The Fe (Iron)-Ni (Nickel) material produced by electroforming shows superior characteristics in terms of coefficient of thermal expansion (CTE) and mechanical properties. This superiority is due to its finer grain size, compared to Fe-Ni produced by the rolling process. Furthermore, when we use the Fe-Ni material to manufacture secondary batteries, it demonstrates equivalent or superior battery characteristics compared to the conventional aluminum (Al) collector material. During thermal shock tests, the Fe-Ni material also shows superior adhesion compared to the traditional Al collector. This advantage is attributed to Fe-Ni's low CTE. Our approach enables the implementation of secondary batteries for power generation on one side and the manufacture of electronic components for power consumption on the other. This creates a new concept for flexible substrate materials.

The Estimation of Battery State of Charge using Corny Network

State of charge (SOC) estimation of lithium-ion batteries has been extensively studied and the estimation accuracy was mainly investigated through the development of various battery models and dynamic estimation algorithms. All battery models, however, contain inherent model bias due to the simplifications and assumptions, which cannot be effectively addressed through the development of various conventional computation and intelligent computation. Consequently, some existing methods performed battery SOC estimation using conventional and intelligent computation have not very accurate to predict the SOC battery characteristics. There some drawbacks in employment deep learning to estimate SOC battery, such as complicated algorithm or network, over fitting and so on. The proposed method, the Corny architecture has narrow layers design. This design has low cost computation and prevent over fitting. The result shows the accuracy of method is very high. The predicted and targeted values are almost merged in a single line. The RMSE and MAX error indexes are very low. That the accuracy of the model is acceptable. The electric vehicle battery can estimate to life longer and more reliable to perform mobility task. Finally, this method also show the accuracy of estimation SOC battery of electric vehicle can be solved by narrow learning layers.

Rancang Bangun Prototipe Solar Home System Menggunakan Baterai Lithium Sebagai Penyimpan Energi

Utilizing the Solar Home System requires a battery as an energy storage medium produced from photovoltaic modules. Today's batteries are lead-carbon Valve Regulated Lead Acid (VRLA) batteries. This type of battery has a 90-95% round-trip efficiency and a deep discharge (DOD) level of 80%. This type of battery is not environmentally friendly because it produces lead acid. Therefore, the development of batteries in the SHS system from lithium battery technology is carried out. Besides being environmentally friendly, its round-trip efficiency is quite good compared to lead-carbon, which is 92-96% with a DOD level of 100%. In this study, it is proposed to apply lithium batteries on a lab scale so that they can assist students in developing scientific fields, especially lithium battery-based energy storage. In addition, this research will describe the process of making and prototyping lithium batteries in solar practicum learning media. From the test results obtained, a laboratory-scale Solar Home System prototype for solar power system practicum using Lithium batteries as Energy Storage. The average effect of charging the battery is 21.09 watts. With the highest battery charging voltage set at 14.08 Vdc. And the highest charging current rate is 1.37 A, with the highest battery charging efficiency rate of 12%. The characteristics of the Lithium battery itself, the DoD shown is also good when the capacity read on the battery meter is 0%. The battery can still supply 15 watts of load for 20 minutes

Method for predicting the size of Ni1/3Mn1/3Co1/3(OH)2 particles precipitated in a stirred-tank semi-batch crystallizer using CFD and particle agglomeration models

NixMnyCoz(OH)2 is widely used as a precursor for the cathode active material LiNixMnyCozO2 in lithium ion batteries, and the precursor size, which determines the size of the active cathode material, affects the characteristics of lithium-ion batteries. This paper proposes a method for predicting the particle size of Ni1/3Mn1/3Co1/3(OH)2 precipitated by semi-batch reaction crystallization. The distribution of supersaturated components formed in the reactor varies with the reactor scale, feed conditions of the raw material solution, and agitation conditions. Therefore, the method presented in this paper considers the effects of these conditions on particle growth. First, to identify the turbulent dispersion and concentration distribution of the supersaturated components formed in the reaction crystallizer, a computational fluid dynamics (CFD) model was constructed consisting of the governing equations of hydrodynamics and the mass balance equations of the supersaturated components considering the production by neutralization and consumption by precipitation. Next, a model of agglomeration was constructed that focused on the balance of the binding and breaking up energies for the particle pairs. The binding energy was quantified based on the bridging between particle pairs by surface deposition. The breaking up-energy was quantified based on the hydrodynamic forces when the agglomerate passes through the impeller. These models were fitted using experimental results for the final average size of the Ni1/3Mn1/3Co1/3(OH)2 secondary aggregate, which was precipitated in a small-scale stirred-tank type semi-batch reaction crystallizer. The models predicted the experimental results of the final average size in a large-scale crystallizer, with the feeding conditions of the raw material solution and stirring conditions as experimental parameters, within ±20%. The models may be used to analyze semi-batch reaction crystallization systems of NixMnyCoz(OH)2 of any composition by adjusting the model parameters according to the procedure developed in this study.

Effect of Aging Path on Degradation Characteristics of Lithium-Ion Batteries in Low-Temperature Environments

Typical usage scenarios for energy storage and electric vehicles (EVs) require lithium-ion batteries (LIBs) to operate under extreme conditions, including varying temperatures, high charge/discharge rates, and various depths of charge and discharge, while also fulfilling vehicle-to-grid (V2G) interaction requirements. This study empirically investigates the impact of ambient temperature, charge/discharge rate, and charge/discharge cut-off voltage on the capacity degradation rate and internal resistance growth of 18,650 commercial LIBs. The charge/discharge rate was found to have the most significant influence on these parameters, particularly the charging rate. These insights contribute to a better understanding of the risks associated with low-temperature aging and can aid in the prevention or mitigation of safety incidents.

Holistic Energy Awareness and Robustness for Intelligent Drones

Drones represent a significant technological shift at the convergence of on-demand cyber-physical systems and edge intelligence. However, realizing their full potential necessitates managing the limited energy resources carefully. Prior work looks at factors such as battery characteristics, intelligent edge sensing considerations, planning, and robustness in isolation. But a global view of energy awareness that considers these factors and looks at various tradeoffs is essential. To this end, we present results from our detailed empirical study of battery charge-discharge characteristics and the impact of altitude and lighting on edge inference accuracy. Our energy models, derived from these observations, predict energy usage while performing various manoeuvres with an error of 5.6%, a 2.5X improvement over the state-of-the-art. Furthermore, we propose a holistic energy-aware multi-drone scheduling system that decreases the energy consumed by 21.14% and the mission times by 46.91% over state-of-the-art baselines. To achieve system robustness in the event of link or drone failure, we observe trends in Packet Delivery Ratio to propose a methodology to establish reliable communication between nodes. We release an open-source implementation of our system. Finally, we tie all of these pieces together using a people-counting case study.

Influence of cathode materials on thermal characteristics of lithium-ion batteries.

In this work, the thermal stability of four types of 18,650 lithium-ion batteries with LiCoO2 (LCO), LiFePO4 (LFP), LiNi0.8Co0.1Mn0.1O2 (NCM811) and LiNi0.8Co0.15Al0.05O2 (NCA) materials as cathodes are experimentally investigated by the accelerating rate calorimeter (ARC) and the isothermal battery testing calorimeter (iso-BTC) under adiabatic and isothermal conditions, respectively. The thermal runaway danger level of these batteries can be ranked as LCO > NCA > NCM811 >> LFP by judging from the values of Tmax and HRmax, nominal. The higher the nickel and cobalt content, the higher the lithium-ion battery capacity, but the worse the thermal stability. The Qtotal of NCA is the largest in the complete standard charge and discharge process, due to that the capacity of NCA is significantly higher than that of the other three batteries, resulting in remarkable increase in Qirre proportioned to the square of the current. When the ambient temperature rises, the energy release decreases owing to the decrease in the internal resistance of the battery. These studies are expected to have important implications for the subsequent safe design of commercial lithium-ion batteries with different cathode materials.

State Estimation of Lithium-ion Battery for Shipboard Applications: Key Challenges and Future Trends

With the aggravation of environmental problems caused by the long-term dependence of shipping traffic on heavy fossil fuels, it is an irreversible development trend for electrified ships to integrate large-capacity battery energy storage systems (ESSs). As the main component, the shipboard lithium-ion battery (LIB) plays an important role in the operation of ship power system to balance the source and load sides. By analyzing the effects of temperature, vibration, humidity and salt spray on battery characteristics in the shipping environment, this paper points out that the characteristics of shipboard LIB have certain differences on the state changes with the land-based batteries. Then, this paper systematically reviews the most commonly used LIB modeling and state estimation methods and their applicability to the shipping environment, including the empirical models, electrochemical models, equivalent circuit models (ECMs) and data-driven models. On this basis, the state estimation methods of state of charge (SOC), state of power (SOP), state of health (SOH), state of energy (SOE) and state of temperature (SOT) are reviewed. Finally, the challenges and prospects of shipboard LIB research are prospected, in the hope of providing inspiration for the development and design of efficient and safe electric ships.

An Overview of BMS Technologies in Electric Vehicles

Batteries are used extensively in high-power applications, including hybrid and electric vehicles (EVs), where the proper battery management system (BMS) is essential to the batteries' dependable and safe performance. The purpose of this study is to provide a quick overview of several important BMS technologies, such as battery charging, state estimation, and battery modelling. The most common battery types utilized in EVs are first examined, and then important BMS technologies are introduced. The most crucial step in determining the energetic range of an EV is the valuation of the electrical properties of batteries. It’s vital to apprehend the variability of battery performance characteristics in order to understand battery behavior in several environments. Finally, the performance characteristics of EV charging and batteries are analyzed to raise the demand for electric vehicles globally.

Comparative Study on the Thermal Characteristics of Solid-State Lithium-Ion Batteries

Comparative Study on the Thermal Characteristics of Solid-State Lithium-Ion Batteries