Comparison of one and two time constant models for lithium ion battery

The fast and accurate modeling topologies are very much essential for power train electrification. The importance of thermal effect is very important in any electrochemical systems and must be considered in battery models because temperature factor has highest importance in transport phenomena and chemical kinetics. The dynamic performance of the lithium ion battery is discussed here and a suitable electrical equivalent circuit is developed to study its response for sudden changes in the output. An effective lithium cell simulation model with thermal dependence is presented in this paper. One series resistor, one voltage source and a single RC block form the proposed equivalent circuit model. The 1 RC and 2 RC Lithium ion battery models are commonly used in the literature are studied and compared. The simulation of Lithium-ion battery 1RC and 2 RC Models are performed by using Matlab/Simulink Software. The simulation results in his paper shows that Lithium-ion battery 1 RC model has more maximum output error of 0.42% than 2 RC Lithium-ion battery model in constant current condition and the maximum output error of 1 RC Lithium-ion battery model is 0.18% more than 2 RC Lithium-ion battery model in UDDS Cycle condition. The simulation results also show that in both simple and complex discharging modes, the error in output is much improved in 2 RC lithium ion battery model when compared to 1 RC Lithium-ion battery model. Thus the paper shows for general applications like in portable electronic design like laptops, Lithium-ion battery 1 RC model is the preferred choice and for automotive and space design applications, Lithium-ion 2 RC model is the preferred choice. In this paper, these simulation results for 1 RC and 2 RC Lithium-ion battery models will be very much useful in the application of practical Lithium-ion battery management systems for electric vehicle applications

A model-based approach for temperature estimation of a lithium-ion battery pack

Temperature is an essential factor that substantially impacts lithium-ion batteries\u27 cycle lifetime, capacity, safety, and heat loss. The present investigation analyses the influence of the lithium-ion battery cell\u27s current rate on its temperature and thermal behaviour. The experiments were fulfilled at different discharge and charge cycles with different current rates. In this study, the thermal behaviour of a lithium-ion battery was analyzed at different current rates by employing a model-based approach from MATLAB. A correlation was seen between the current rate of the lithium-ion battery and the most remarkable temperature growth. The results would produce a more robust understanding of the temperature evolution of the lithium-ion battery cell for various applications. A smaller temperature was seen on the upper part of the lithium-ion battery pack

Running Test of VVVF Inverter Type Railcar Using Lithium Ion Battery

Lithium ion battery was applied to the running of VVVF inverter type railcar. 15kWh of Mn type lithium ion battery was used. The relation between running time and voltage, current and integrating watt was investigated. The running test was also carried out using VVVF inverter type railcar to investigate charge performance due to regenerative energy. Lithium ion battery module was quickly charged for three times at rate of 4.68C by regenerative braking system. It was estimated that the effect of energy saving was about 22% by the charge of lithium ion battery from regenerative energy

Applying different configurations for the thermal management of a lithium titanate oxide battery pack

This investigation’s primary purpose was to illustrate the cooling mechanism within a lithium titanate oxide lithium-ion battery pack through the experimental measurement of heat generation inside lithium titanate oxide batteries. Dielectric water/glycol (50/50), air and dielectric mineral oil were selected for the lithium titanate oxide battery pack’s cooling purpose. Different flow configurations were considered to study their thermal effects. Within the lithium-ion battery cells in the lithium titanate oxide battery pack, a time-dependent amount of heat generation, which operated as a volumetric heat source, was employed. It was assumed that the lithium-ion batteries within the battery pack had identical initial temperature conditions in all of the simulations. The lithium-ion battery pack was simulated by ANSYS to determine the temperature gradient of the cooling system and lithium-ion batteries. Simulation outcomes demonstrated that the lithium-ion battery pack’s temperature distributions could be remarkably influenced by the flow arrangement and fluid coolant type

Real-time state of charge estimation of electrochemical model for lithium-ion battery

This paper proposes the real-time Kalman filter based observer for Lithium-ion concentration estimation for the electrochemical battery model. Since the computation limitation of real-time battery management system (BMS) micro-processor, the battery model which is utilized in observer has been further simplified. In this paper, the Kalman filter based observer is applied on a reduced order model of single particle model to reduce computational burden for real-time applications. Both solid phase surface lithium concentration and battery state of charge (SoC) can be estimated with real-time capability. Software simulation results and the availability comparison of observers in different Hardware-in- the-loop simulation setups demonstrate the performance of the proposed method in state estimation and real-time application

Global sensitivity analysis of the single particle lithium-ion battery model with electrolyte

The importance of global sensitivity analysis (GSA) has been well established in many scientific areas. However, despite its critical role in evaluating a model’s plausibility and relevance, most lithium ion battery models are published without any sensitivity analysis. In order to improve the lifetime performance of battery packs, researchers are investigating the application of physics based electrochemical models, such as the single particle model with electrolyte (SPMe). This is a challenging research area from both the parameter estimation and modelling perspective. One key challenge is the number of unknown parameters: the SPMe contains 31 parameters, many of which are themselves non-linear functions of other parameters. As such, relatively few authors have tackled this parameter estimation problem. This is exacerbated because there are no GSAs of the SPMe which have been published previously. This article addresses this gap in the literature and identifies the most sensitive parameter, preventing time being wasted on refining parameters which the output is insensitive to

UV and EB Curable Binder Technology for Lithium Ion Batteries and UltraCapacitors

the basic feasibility of using UV curing technology to produce Lithium ion battery electrodes at speeds over 200 feet per minute has been shown. A unique set of UV curable chemicals were discovered that were proven to be compatible with a Lithium ion battery environment with the adhesion qualities of PVDF

Thermal Analysis of Cold Plate with Different Configurations for Thermal Management of a Lithium-Ion Battery

Thermal analysis and thermal management of lithium-ion batteries for utilization in electric vehicles is vital. In order to investigate the thermal behavior of a lithium-ion battery, a liquid cooling design is demonstrated in this research. The influence of cooling direction and conduit distribution on the thermal performance of the lithium-ion battery is analyzed. The outcomes exhibit that the appropriate flow rate for heat dissipation is dependent on different configurations for cold plate. The acceptable heat dissipation condition could be acquired by adding more cooling conduits. Moreover, it was distinguished that satisfactory cooling direction could efficiently enhance the homogeneity of temperature distribution of the lithium-ion battery

In-depth Life Cycle Cost Analysis of a Li-ion Battery-based Hybrid Diesel-Electric Multiple Unit

This study analyzes the life cycle costs of railway projects involving hybrid diesel-electric multiple units, focusing on the influence of lithium-ion battery technologies and energy management strategies. Specifically, 3 lithium-ion battery technologies and 6 energy management strategies are proposed, leading to a sensitivity analysis composed of 18 cases. In addition, for each case an approach for the optimal sizing of the diesel generator and lithium-ion battery is proposed. A scenario based on a real railway line is introduced and the results are compared to a traditional diesel-electric multiple unit. Potential life cycle cost savings of 16.0% are obtained when deploying a global optimization-based energy management strategy and LTO batteries

Thermal Simulation of Phase Change Material for Cooling of a Lithium-Ion Battery Pack

A new heat transfer enhancement approach was proposed for the cooling system of lithium-ion batteries. A three-dimensional numerical simulation of the passive thermal management system for a battery pack was accomplished by employing ANSYS Fluent (Canonsburg, PA, USA). Phase change material was used for the thermal management of lithium-ion battery modules and as the heat transmission source to decrease battery temperature in fast charging and discharge conditions. Constant current charge and discharge were applied to lithium-ion battery modules. In the experimental part of the research, an isothermal battery calorimeter was used to determine the heat dissipation of lithium-ion batteries. Thermal performance was simulated for the presence of phase change material composites. Simulation outcomes demonstrate that phase change material cooling considerably decreases the lithium-ion battery temperature increase during fast charging and discharging conditions use. The greatest temperature at the end of 9 C, 7 C, 5 C, and 3 C charges and discharges were approximately 49.7, 44.6, 38.4, and 33.1 °C, respectively, demonstrating satisfactory performance in lithium-ion battery thermal homogeneity of the passive thermal management system