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Hansdieter Wiemhofer - One of the best experts on this subject based on the ideXlab platform.
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the impact of calendar aging on the thermal stability of a limn2o4 li ni1 3mn1 3co1 3 o2 graphite lithium ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.
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a detailed thermal study of a li ni0 33co0 33mn0 33 o2 limn2o4 based lithium ion Cell by accelerating rate and differential scanning calorimetry
Journal of Power Sources, 2014Co-Authors: P Roder, N Baba, Hansdieter WiemhoferAbstract:Abstract Accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were used to study the thermal behaviour of a commercially available Lithium-Ion Cell. Both the complete Cell (pouch type, 2 Ah) and its electrode materials, respectively, were investigated. As positive electrode material a blend system consisting of NCM (=Li[Ni 0.33 Co 0.33 Mn 0.33 ]O 2 ) and LMO (=LiMn 2 O 4 ) with a weight ratio of 4:1 was identified. The main exothermic behaviour is dominated by the positive electrode–electrolyte reaction. ARC studies on the positive electrode material in presence of our reference electrolyte show an inhibiting effect of the conducting salt LiPF 6 towards the oxidation of the organic based electrolyte by released oxygen. X-ray diffraction measurements were performed to study the thermal decomposition behaviour of the positive active material. Both the blend system and the single components, NCM and LMO, were investigated at different temperatures. A significant phase transformation from the hexagonal layered to a cubic structure as well as various reduction products could be identified. Finally, the thermal behaviour of the NCM/LMO-blend and its single phases, NCM and LMO, at different states of charge (SOC) was investigated. Therefore, detailed investigations based on differential scanning calorimetry (DSC) and cyclic voltammetry (CV) were performed.
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The impact of calendar aging on the thermal stability of a LiMn2O4–Li(Ni1/3Mn1/3Co1/3)O2/graphite Lithium-Ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.
Ralph E. White - One of the best experts on this subject based on the ideXlab platform.
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comparison of single particle and equivalent circuit analog models for a lithium ion Cell
Journal of Power Sources, 2011Co-Authors: Saeed Khaleghi Rahimian, Sean Rayman, Ralph E. WhiteAbstract:The physics-based single particle (SP) model was compared to the semi-empirical equivalent circuit analog (ECA) model to predict the Cell voltage under constant current charge and discharge for different sets of Li-ion Cell data. The parameters of the models were estimated for each set of data using nonlinear least squares regression. In order to enhance the probability of finding the global optima, a combination of the trust region method with a genetic algorithm was applied to minimize the objective function (the sum of squared residuals). Several statistical quantities such as sum of the squared errors, adjusted R2, root mean squared error, confidence intervals of the parameters, and prediction bounds were included to compare the models. A significance test (t test) on the parameters and the analysis of the variances (F and χ2 tests) were also performed to discriminate between the goodness of the fit obtained from the two models. The statistical results indicate that the SP model superiorly predicts all sets of data compared to the ECA model, while the computation times of both models are on the same order of magnitude.
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single particle model for a lithium ion Cell thermal behavior
Journal of The Electrochemical Society, 2011Co-Authors: Godfrey Sikha, Ralph E. WhiteAbstract:15 developed a thermal model for the LiCoO2-mesocarbon microbead MCMB pouch Cells based on the PP model and obtained good agreement between model predictions and experimental data. A disadvantage common to the P2D model and the PP model is the long simulation time due to the large number of nonlinear equations, so these models become computationally inefficient for simulating conditions such as cycling behavior and series/parallel configuration of stacked Cells in battery packs. To improve computational run time without compromising accuracy, the singleparticle model SP modelRef. 3 and 16 was proposed. The SP model ignores the detailed distribution of local concentration and potential in the solution phase and instead accounts for a lumped solution resistance term. Furthermore, the local reaction currents across the porous electrode are assumed to be constant, which allows treatment of a porous electrode as a large number of single particles, all of which are subjected to the same conditions. These assumptions are reasonable for low applied current densities, thin electrodes, and highly conductive electrodes. In such cases the overpotential is primarily affected by the diffusion in the solid state. At high current densities, the concentration gradients in the electrolyte become important. The model presented here does not include these concentration gradients and is consequently limited to low to moderate current densities. These assumptions simplify the model equations significantly. The SP model using a two term polynomial approximation shows good agreement with the detailed PP model for charge/discharge below 1C, where C denotes the Cell capacity. 3 In this work, the single-particle model is extended to include thermal effects by adding the energy balance equation to the SP model. Instead of using a two term polynomial approximation, the solid phase diffusion equations are solved by the eigenfunction expansion method, which improved the accuracy of the model. Parameters in this SP thermal model are estimated by fitting the simulated discharge curves up to 1C rate with the experimental data obtained on Lithium-Ion pouch Cells. Also, good agreement between the SP thermal model and the PP thermal model presented in Ref. 15 is obtained.
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Capacity fade analysis of a lithium ion Cell
Journal of Power Sources, 2008Co-Authors: Qi Zhang, Ralph E. WhiteAbstract:Abstract A physics-based single particle model was used to simulate the life cycling data of a lithium ion Cell. The simulation indicates that there are probably three stages of capacity fade in a lithium ion Cell used at low rates. In the first stage, lithium ions are lost to a film formation reaction (e.g. SEI formation) and, consequently, the cathode becomes less intercalated during cycling. In the second stage, the loss of active cathode material outpaces the loss of lithium ions and the cathode gradually becomes more intercalated at the end of discharge. The anode is the limiting electrode in stages one and two and the change in the anode voltage causes the Cell to reach end of discharge voltage. In the third stage, the limiting electrode shifts from the anode to the cathode, and the anode becomes increasingly less discharged at the end of discharge. Thus, more and more “cyclable” lithium ions are left inside the anode, which causes additional capacity fade.
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Short communication Capacity fade analysis of a lithium ion Cell
2008Co-Authors: Qi Zhang, Ralph E. WhiteAbstract:A physics-based single particle model was used to simulate the life cycling data of a lithium ion Cell. The simulation indicates that there are probably three stages of capacity fade in a lithium ion Cell used at low rates. In the first stage, lithium ions are lost to a film formation reaction (e.g. SEI formation) and, consequently, the cathode becomes less intercalated during cycling. In the second stage, the loss of active cathode material outpaces the loss of lithium ions and the cathode gradually becomes more intercalated at the end of discharge. The anode is the limiting electrode in stages one and two and the change in the anode voltage causes the Cell to reach end of discharge voltage. In the third stage, the limiting electrode shifts from the anode to the cathode, and the anode becomes increasingly less discharged at the end of discharge. Thus, more and more “cyclable” lithium ions are left inside the anode, which causes additional capacity fade. © 2008 Elsevier B.V. All rights reserved.
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Parameter Estimation and Life Modeling of Lithium-Ion Cells
Journal of The Electrochemical Society, 2008Co-Authors: Shriram Santhanagopalan, Qi Zhang, Karthikeyan Kumaresan, Ralph E. WhiteAbstract:The Lithium-Ion Cell is among the most popular candidates considered actively as a replacement for nickel-based batteries in automobile, small-electronics, satellite, and several other applications. This demand has fueled the need for improved performance and safety of the Lithium-Ion system. Consequently, a substantial amount of work has gone into understanding the mechanism of the capacity fade occurring in the battery experimentally and via rigorous theoretical analysis. 1-18
Patrick Roder - One of the best experts on this subject based on the ideXlab platform.
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the impact of calendar aging on the thermal stability of a limn2o4 li ni1 3mn1 3co1 3 o2 graphite lithium ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.
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The impact of calendar aging on the thermal stability of a LiMn2O4–Li(Ni1/3Mn1/3Co1/3)O2/graphite Lithium-Ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.
Paul Lagaly - One of the best experts on this subject based on the ideXlab platform.
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the impact of calendar aging on the thermal stability of a limn2o4 li ni1 3mn1 3co1 3 o2 graphite lithium ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.
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The impact of calendar aging on the thermal stability of a LiMn2O4–Li(Ni1/3Mn1/3Co1/3)O2/graphite Lithium-Ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.
Jorg Ziegler - One of the best experts on this subject based on the ideXlab platform.
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the impact of calendar aging on the thermal stability of a limn2o4 li ni1 3mn1 3co1 3 o2 graphite lithium ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.
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The impact of calendar aging on the thermal stability of a LiMn2O4–Li(Ni1/3Mn1/3Co1/3)O2/graphite Lithium-Ion Cell
Journal of Power Sources, 2014Co-Authors: Patrick Roder, Barbara Stiaszny, Jorg Ziegler, Nilufer Baba, Paul Lagaly, Hansdieter WiemhoferAbstract:Abstract Aging of Lithium-Ion Cells is an inevitable phenomenon limiting the lifetime. Undesirable side reactions during cycle or calendar aging may affect the performance of all components of the Lithium-Ion Cell. This results in a decreased capacity and an increase in the overall Cell impedance. Based on electrochemical and physical characterization methods, the aging behavior during calendar aging of a 18650-Cell, containing a blend of LiMn 2 O 4 and Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 (NMC) as cathode material and graphite as anode material was systematically investigated. To understand how the safety behavior of a Lithium-Ion Cell changes with aging, accelerating rate calorimetry (ARC) and differential scanning calorimetry (DSC) were applied. With these methods the thermal stability behavior of the complete Lithium-Ion Cell and its respective cathode and anode material were investigated. The focus of this work was it to generate first cause–effect relations between the aging under one exemplary aging condition and the thermal stability of a Lithium-Ion battery both on Cell and material level.