Incremental thermo-electric CFD modeling of a high-energy Lithium-Titanate Oxide battery cell in different temperatures: A comparative study

This paper presents the concept of a hybrid thermal management system (TMS) including natural convection, heat pipe, and air cooling assisted heat pipe (ACAH) for electric vehicles. Experimental and numerical tests are described to predict the thermal behavior of a lithium titanate oxide (LTO) battery cell in a fast discharging process (8C rate). Specifications of different cooling techniques are deliberated and compared. The mathematical models are solved by COMSOL Multiphysics® (Stockholm, Sweden), the commercial computational fluid dynamics (CFD) software. The simulation results are validated against experimental data with an acceptable error range. The results specify that the maximum cell temperatures for the cooling systems of natural convection, heat pipe, and ACAH reach 56, 46.3, and 38.3 °C, respectively. We found that the maximum cell temperature experiences a 17.3% and 31% reduction with the heat pipe and ACAH, respectively, compared with natural convection.

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Heat Loss Measurement of Lithium Titanate Oxide Batteries under Fast Charging Conditions by Employing Isothermal Calorimeter

Batteries ◽

10.3390/batteries4040059 ◽

2018 ◽

Vol 4 (4) ◽

pp. 59 ◽

Cited By ~ 5

Author(s):

Seyed Madani ◽

Erik Schaltz ◽

Søren Knudsen Kær

Keyword(s):

Lithium Ion Batteries ◽

Heat Loss ◽

Lithium Ion ◽

Lithium Titanate ◽

Constant Current ◽

Maximum Temperature ◽

Battery Cell ◽

Lithium Titanate Oxide ◽

Temperature Efficiency ◽

Constant Current Charge

To understand better the thermal behaviour of lithium-ion batteries under different working conditions, various experiments were applied to a 13 Ah Altairnano lithium titanate oxide battery cell by means of isothermal battery calorimeter. Several parameters were measured such as the battery surface temperature, voltage, current, power, heat flux, maximum temperature and power area. In addition, the efficiency was calculated. Isothermal battery calorimeter was selected as the most appropriate method for heat loss measurements. Temperatures on the surface of the battery were measured by employing four contact thermocouples (type K). In order to determine the heat loss of the battery, constant current charge and discharge pulses at sixteen different C-rates were applied to the battery. It was seen that the charge and discharge C-rates has a considerable influence on the thermal behaviours of lithium-ion batteries. In this research paper, the C-rate was linked to the peak temperature, efficiency and heat loss and it was concluded that they are linear dependent on the C-rate. In addition, the outcomes of this investigation can be used for battery thermal modelling and design of thermal management systems.

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An Electrical Equivalent Circuit Model of a Lithium Titanate Oxide Battery

Batteries ◽

10.3390/batteries5010031 ◽

2019 ◽

Vol 5 (1) ◽

pp. 31 ◽

Cited By ~ 14

Author(s):

Seyed Madani ◽

Erik Schaltz ◽

Søren Knudsen Kær

Keyword(s):

Lithium Ion Battery ◽

Equivalent Circuit Model ◽

Lithium Ion ◽

Lithium Titanate ◽

Electrical Circuit ◽

Battery Cell ◽

Electrical Equivalent Circuit ◽

Battery Model ◽

Lithium Titanate Oxide ◽

Voltage Performance

A precise lithium-ion battery model is required to specify their appropriateness for different applications and to study their dynamic behavior. In addition, it is important to design an efficient battery system for power applications. In this investigation, a second-order equivalent electrical circuit battery model, which is the most conventional method of characterizing the behavior of a lithium-ion battery, was developed. The current pulse procedure was employed for parameterization of the model. The construction of the model was described in detail, and a battery model for a 13 Ah lithium titanate oxide battery cell was demonstrated. Comprehensive characterization experiments were accomplished for an extensive range of operating situations. The outcomes were employed to parameterize the suggested dynamic model of the lithium titanate oxide battery cell. The simulation outcomes were compared to the laboratory measurements. In addition, the proposed lithium-ion battery model was validated. The recommended model was assessed, and the proposed model was able to anticipate precisely the current and voltage performance.

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Simulation of Thermal Behaviour of a Lithium Titanate Oxide Battery

Energies ◽

10.3390/en12040679 ◽

2019 ◽

Vol 12 (4) ◽

pp. 679 ◽

Cited By ~ 6

Author(s):

Seyed Madani ◽

Erik Schaltz ◽

Søren Knudsen Kær

Keyword(s):

Heat Generation ◽

Electrochemical Behaviour ◽

Three Dimensional ◽

Lithium Ion ◽

Lithium Titanate ◽

Test System ◽

Three Dimensional Model ◽

Battery Cell ◽

Cell Parameters ◽

Lithium Titanate Oxide

One of the reasonable possibilities to investigate the battery behaviour under various temperature and current conditions is the development of a model of the lithium-ion batteries and then by employing the simulation technique to anticipate their behaviour. This method not only can save time but also they can predict the behaviour of the batteries through simulation. In this investigation, a three-dimensional model is developed to simulate thermal and electrochemical behaviour of a 13Ah lithium-ion battery. In addition, the temperature dependency of the battery cell parameters was considered in the model in order to investigate the influence of temperature on various parameters such as heat generation during battery cell operation. Maccor automated test system and isothermal battery calorimeter were used as experimental setup to validate the thermal model, which was able to predict the heat generation rate and temperature at different positions of the battery. The three-dimensional temperature distributions which were achieved from the modelling and experiment were in well agreement with each other throughout the entire of discharge cycling at different environmental temperatures and discharge rates.

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An Experimental Analysis of Entropic Coefficient of a Lithium Titanate Oxide Battery

Energies ◽

10.3390/en12142685 ◽

2019 ◽

Vol 12 (14) ◽

pp. 2685 ◽

Cited By ~ 1

Author(s):

Seyed Saeed Madani ◽

Erik Schaltz ◽

Søren Knudsen Kær

Keyword(s):

Heat Generation ◽

Thermal Cycle ◽

Lithium Ion ◽

Lithium Titanate ◽

State Of Charge ◽

Time Duration ◽

Battery Cell ◽

Temperature State ◽

Lithium Titanate Oxide ◽

Temperature Levels

In order to understand the thermal behaviour of a lithium-ion battery, the heat generation within the cell should be determined. The entropic heat coefficient is necessary to determine for the heat generation calculation. The entropic heat coefficient is one of the most important factors, which affects the magnitude of the reversible heat. The purpose of this research is to analyze and investigate the effect of different parameters on the entropic coefficient of lithium titanate oxide batteries. In this research, a lithium ion pouch cell was examined in both charging and discharging situations. The state of charge levels range was considered from 10% to 90%, and vice versa, in 10% increments. The temperature levels vary from 5 °C to 55 °C and the voltage levels vary from 1.5 V to 2.8 V. The effect of different parameters such as initial temperature, state of charge, thermal cycle, time duration for thermal cycles, and procedure prior to the thermal cycle on the entropic coefficient of lithium titanate oxide batteries were investigated. It was concluded that there is a strong influence of the battery cell state of charge on the entropic heat coefficient compared with other parameters.

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Impedance Analysis of Layer Structured NBT–CBT Mixed Ceramics

Modern Physics Letters B ◽

10.1142/s0217984998000536 ◽

1998 ◽

Vol 12 (11) ◽

pp. 433-441 ◽

Cited By ~ 1

Author(s):

P. S. Rama Sastry ◽

T. Bhimasankaram ◽

G. S. Kumar ◽

G. Prasad

Keyword(s):

Comparative Study ◽

Complex Impedance ◽

Impedance Analysis ◽

Equivalent Circuits ◽

Impedance Spectra ◽

Ceramic System ◽

Different Temperatures ◽

Mixed Ceramics ◽

Mixed Ceramic ◽

Complex Impedance Spectra

Complex impedance spectra of ferroelectric mixed ceramic system ( Na 0.5 Bi 0.5)1-x Ca x Bi 4 Ti 4 O 15 with x=0, 0.1, 0.3, 0.5, 0.7 and 1 was studied as a function of frequency and temperature in the range 1 KHz to 10 MHz and 30°C to 620°C respectively. Equivalent circuits involving resistive and capacitive elements at different temperatures, activation energies of relaxations and conduction were evaluated using impedance plots. A comparative study of impedance and conductivity facilities an insight in understanding the electrical nature of these electroceramics.

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A Comparative Study of Soldering Temperatures and Materials on the Reliability of Photovoltaic Modules

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.562-564.188 ◽

2012 ◽

Vol 562-564 ◽

pp. 188-191

Author(s):

Keh Moh Lin ◽

Yang Hsien Lee ◽

Wen Yeong Huang ◽

Po Chun Hsu ◽

Chin Yang Huang ◽

...

Keyword(s):

Comparative Study ◽

Lead Free ◽

Automatic Process ◽

Lead Free Solder ◽

Snagcu Solder ◽

Photovoltaic Modules ◽

Soldering Process ◽

Different Temperatures ◽

Free Solder

To find out the important factors which decisively affect the soldering quality of photovoltaic modules, solar cells were soldered under different conditions (different temperatures, PbSn vs. SnAgCu solder, manual vs. semi-automatic). Experimental results show that the soldering quality of PbSn under 350°C in the semi-automatic soldering process was quite stable while the soldering quality of lead-free solder was generally unacceptable in the manual or semi-automatic process under different temperatures. This result indicates that the soldering process with lead-free solder still needs to be further improved. It was also found that most cracks were formed on the interface between the solder and the silver paste and then expanded outwards.

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