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Pradeep R Guduru - One of the best experts on this subject based on the ideXlab platform.
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quantifying capacity loss due to solid electrolyte interphase layer formation on Silicon negative Electrodes in lithium ion batteries
Journal of Power Sources, 2012Co-Authors: Siva P V Nadimpalli, Vijay A Sethuraman, Michael J Chon, Brett L. Lucht, Swapnil Dalavi, Vivek B Shenoy, Pradeep R GuduruAbstract:Abstract Charge lost per unit surface area of a Silicon Electrode due to the formation of solid-electrolyte-interphase (SEI) layer during initial lithiation was quantified, and the species that constitute this layer were identified. Coin cells made with Si thin-film Electrodes were subjected to a combination of galvanostatic and potentiostatic lithiation and delithiation cycles to accurately measure the capacity lost to SEI layer formation. While the planar geometry of amorphous thin films allows accurate calculation of surface area, creation of additional surface by cracking was prevented by minimizing the thickness of the Si film. The cycled Electrodes were analyzed with X-ray photoelectron spectroscopy to characterize the composition of the SEI layer. The charge lost due to SEI formation measured from coin cell experiments was found to be in good agreement with the first-cycle capacity loss during the initial lithiation of a Si(100) crystal with planar geometry. The methodology presented in this work is expected to provide a useful practical tool for battery-material developers in estimating the expected capacity loss due to first cycle SEI layer formation and in choosing an appropriate particle size distribution that balances mechanical integrity and the first cycle capacity loss in large volume expansion Electrodes for lithium-ion batteries.
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in situ measurements of stress potential coupling in lithiated Silicon
Journal of The Electrochemical Society, 2010Co-Authors: Vijay A Sethuraman, Venkat Srinivasan, Allan F Bower, Pradeep R GuduruAbstract:An analysis of the dependence of electric potential on the state of stress of a lithiated-Silicon Electrode is presented. Based on the Larche and Cahn chemical potential for a solid solution, a thermodynamic argument is made for the existence of the stresspotential coupling in lithiated Silicon; based on the known properties of the material, the magnitude of the coupling is estimated to be 60 mV/GPa in thin-film geometry. An experimental investigation is carried out on Silicon thin-film Electrodes in which the stress is measured in situ during electrochemical lithiation and delithiation. By progressively varying the stress through incremental delithiation, the relation between stress change and electric-potential change is measured to be 100–120 mV/GPa, which is of the same order of magnitude as the prediction of the analysis. The importance of the coupling is discussed in interpreting the hysteresis observed in the potential vs state-of-charge plots and the role of stress in modifying the maximum charge capacity of a Silicon Electrode under stress.
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in situ measurements of stress evolution in Silicon thin films during electrochemical lithiation and delithiation
Journal of Power Sources, 2010Co-Authors: Vijay A Sethuraman, Michael J Chon, Maxwell Shimshak, Venkat Srinivasan, Pradeep R GuduruAbstract:We report in situ measurements of stress evolution in a Silicon thin-film Electrode during electrochemical lithiation and delithiation by using the multi-beam optical sensor (MOS) technique. Upon lithiation, due to substrate constraint, the Silicon Electrode initially undergoes elastic deformation, resulting in rapid rise of compressive stress. The Electrode begins to deform plastically at a compressive stress of ca. −1.75 GPa; subsequent lithiation results in continued plastic strain, dissipating mechanical energy. Upon delithiation, the Electrode first undergoes elastic straining in the opposite direction, leading to a tensile stress of ca. 1 GPa; subsequently, it deforms plastically during the rest of delithiation. The plastic flow stress evolves continuously with lithium concentration. Thus, mechanical energy is dissipated in plastic deformation during both lithiation and delithiation, and it can be calculated from the stress measurements; we show that it is comparable to the polarization loss. Upon current interruption, both the film stress and the Electrode potential relax with similar time constants, suggesting that stress contributes significantly to the chemical potential of lithiated Silicon.
Vijay A Sethuraman - One of the best experts on this subject based on the ideXlab platform.
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quantifying capacity loss due to solid electrolyte interphase layer formation on Silicon negative Electrodes in lithium ion batteries
Journal of Power Sources, 2012Co-Authors: Siva P V Nadimpalli, Vijay A Sethuraman, Michael J Chon, Brett L. Lucht, Swapnil Dalavi, Vivek B Shenoy, Pradeep R GuduruAbstract:Abstract Charge lost per unit surface area of a Silicon Electrode due to the formation of solid-electrolyte-interphase (SEI) layer during initial lithiation was quantified, and the species that constitute this layer were identified. Coin cells made with Si thin-film Electrodes were subjected to a combination of galvanostatic and potentiostatic lithiation and delithiation cycles to accurately measure the capacity lost to SEI layer formation. While the planar geometry of amorphous thin films allows accurate calculation of surface area, creation of additional surface by cracking was prevented by minimizing the thickness of the Si film. The cycled Electrodes were analyzed with X-ray photoelectron spectroscopy to characterize the composition of the SEI layer. The charge lost due to SEI formation measured from coin cell experiments was found to be in good agreement with the first-cycle capacity loss during the initial lithiation of a Si(100) crystal with planar geometry. The methodology presented in this work is expected to provide a useful practical tool for battery-material developers in estimating the expected capacity loss due to first cycle SEI layer formation and in choosing an appropriate particle size distribution that balances mechanical integrity and the first cycle capacity loss in large volume expansion Electrodes for lithium-ion batteries.
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in situ measurements of stress potential coupling in lithiated Silicon
Journal of The Electrochemical Society, 2010Co-Authors: Vijay A Sethuraman, Venkat Srinivasan, Allan F Bower, Pradeep R GuduruAbstract:An analysis of the dependence of electric potential on the state of stress of a lithiated-Silicon Electrode is presented. Based on the Larche and Cahn chemical potential for a solid solution, a thermodynamic argument is made for the existence of the stresspotential coupling in lithiated Silicon; based on the known properties of the material, the magnitude of the coupling is estimated to be 60 mV/GPa in thin-film geometry. An experimental investigation is carried out on Silicon thin-film Electrodes in which the stress is measured in situ during electrochemical lithiation and delithiation. By progressively varying the stress through incremental delithiation, the relation between stress change and electric-potential change is measured to be 100–120 mV/GPa, which is of the same order of magnitude as the prediction of the analysis. The importance of the coupling is discussed in interpreting the hysteresis observed in the potential vs state-of-charge plots and the role of stress in modifying the maximum charge capacity of a Silicon Electrode under stress.
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in situ measurements of stress evolution in Silicon thin films during electrochemical lithiation and delithiation
Journal of Power Sources, 2010Co-Authors: Vijay A Sethuraman, Michael J Chon, Maxwell Shimshak, Venkat Srinivasan, Pradeep R GuduruAbstract:We report in situ measurements of stress evolution in a Silicon thin-film Electrode during electrochemical lithiation and delithiation by using the multi-beam optical sensor (MOS) technique. Upon lithiation, due to substrate constraint, the Silicon Electrode initially undergoes elastic deformation, resulting in rapid rise of compressive stress. The Electrode begins to deform plastically at a compressive stress of ca. −1.75 GPa; subsequent lithiation results in continued plastic strain, dissipating mechanical energy. Upon delithiation, the Electrode first undergoes elastic straining in the opposite direction, leading to a tensile stress of ca. 1 GPa; subsequently, it deforms plastically during the rest of delithiation. The plastic flow stress evolves continuously with lithium concentration. Thus, mechanical energy is dissipated in plastic deformation during both lithiation and delithiation, and it can be calculated from the stress measurements; we show that it is comparable to the polarization loss. Upon current interruption, both the film stress and the Electrode potential relax with similar time constants, suggesting that stress contributes significantly to the chemical potential of lithiated Silicon.
Brett L. Lucht - One of the best experts on this subject based on the ideXlab platform.
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Thermal Decomposition of the Solid Electrolyte Interphase (SEI) on Silicon Electrodes for Lithium Ion Batteries
Chemistry of Materials, 2017Co-Authors: Taeho Yoon, Mickdy S. Milien, Bharathy S. Parimalam, Brett L. LuchtAbstract:Thermal behavior of the solid electrolyte interphase (SEI) on a Silicon Electrode for lithium ion batteries has been investigated by TGA. In order to provide a better understanding of the thermal decomposition of the SEI on Silicon, the thermal decomposition behavior of independently synthesized lithium ethylene dicarbonate (LEDC) was investigated as a model SEI. The model SEI (LEDC) has three stages of thermal decomposition. Over the temperature range of 50–300 °C, LEDC decomposes to evolve CO2 and C2H4 gases leaving lithium propionate (CH3CH2CO2Li) and Li2CO3 as solid residues. The lithium propionate decomposes over the temperature range of 300–600 °C to evolve pentanone leaving Li2CO3 as a residual solid. Finally, the Li2CO3 decomposes over 600 °C to evolve CO2 leaving Li2O as a residual solid. A very similar thermal decomposition process is observed for the SEI generated on cycled Silicon Electrodes. However, two additional thermal decomposition reactions were observed characteristic of LixPOyFz at 30...
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quantifying capacity loss due to solid electrolyte interphase layer formation on Silicon negative Electrodes in lithium ion batteries
Journal of Power Sources, 2012Co-Authors: Siva P V Nadimpalli, Vijay A Sethuraman, Michael J Chon, Brett L. Lucht, Swapnil Dalavi, Vivek B Shenoy, Pradeep R GuduruAbstract:Abstract Charge lost per unit surface area of a Silicon Electrode due to the formation of solid-electrolyte-interphase (SEI) layer during initial lithiation was quantified, and the species that constitute this layer were identified. Coin cells made with Si thin-film Electrodes were subjected to a combination of galvanostatic and potentiostatic lithiation and delithiation cycles to accurately measure the capacity lost to SEI layer formation. While the planar geometry of amorphous thin films allows accurate calculation of surface area, creation of additional surface by cracking was prevented by minimizing the thickness of the Si film. The cycled Electrodes were analyzed with X-ray photoelectron spectroscopy to characterize the composition of the SEI layer. The charge lost due to SEI formation measured from coin cell experiments was found to be in good agreement with the first-cycle capacity loss during the initial lithiation of a Si(100) crystal with planar geometry. The methodology presented in this work is expected to provide a useful practical tool for battery-material developers in estimating the expected capacity loss due to first cycle SEI layer formation and in choosing an appropriate particle size distribution that balances mechanical integrity and the first cycle capacity loss in large volume expansion Electrodes for lithium-ion batteries.
Huajian Gao - One of the best experts on this subject based on the ideXlab platform.
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Failure progression in the solid electrolyte interphase (SEI) on Silicon Electrodes
Nano Energy, 2020Co-Authors: Kai Guo, Ravi Kumar, Xingcheng Xiao, Brian W. Sheldon, Huajian GaoAbstract:Abstract Maintaining an electrochemically and mechanically stable solid electrolyte interphase (SEI) is of fundamental importance to the performance of high capacity anode materials such as Silicon. In this study, a novel approach is utilized to apply controlled strains to SEI films on patterned Si Electrodes. Mechanical failure mechanisms of SEI are investigated with integrated in situ AFM, ex situ FIB measurements and finite element modeling. Cross-sectional images reveal that the SEI has a bilayer structure, and through-thickness cracks appear inside of the outer SEI and arrest at the outer and inner SEI interface. The absence of cracking of the inner SEI layer implies that it has a high fracture toughness, and that it is possible to create an inner SEI which exhibits excellent strain tolerance compared to the outer layer. Interfacial delamination occurs between the outer and inner SEI layers while the inner layer is still well adhered to the underlying Si. The experimental and modeling results indicate that the inner SEI layer is sufficient for passivation of the Si surface. More broadly, the present work provides important guidelines for producing inner SEI layers that can simultaneously satisfy both electrochemical and mechanical criteria for long term passivation of Silicon Electrode surfaces.
Michael J Chon - One of the best experts on this subject based on the ideXlab platform.
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quantifying capacity loss due to solid electrolyte interphase layer formation on Silicon negative Electrodes in lithium ion batteries
Journal of Power Sources, 2012Co-Authors: Siva P V Nadimpalli, Vijay A Sethuraman, Michael J Chon, Brett L. Lucht, Swapnil Dalavi, Vivek B Shenoy, Pradeep R GuduruAbstract:Abstract Charge lost per unit surface area of a Silicon Electrode due to the formation of solid-electrolyte-interphase (SEI) layer during initial lithiation was quantified, and the species that constitute this layer were identified. Coin cells made with Si thin-film Electrodes were subjected to a combination of galvanostatic and potentiostatic lithiation and delithiation cycles to accurately measure the capacity lost to SEI layer formation. While the planar geometry of amorphous thin films allows accurate calculation of surface area, creation of additional surface by cracking was prevented by minimizing the thickness of the Si film. The cycled Electrodes were analyzed with X-ray photoelectron spectroscopy to characterize the composition of the SEI layer. The charge lost due to SEI formation measured from coin cell experiments was found to be in good agreement with the first-cycle capacity loss during the initial lithiation of a Si(100) crystal with planar geometry. The methodology presented in this work is expected to provide a useful practical tool for battery-material developers in estimating the expected capacity loss due to first cycle SEI layer formation and in choosing an appropriate particle size distribution that balances mechanical integrity and the first cycle capacity loss in large volume expansion Electrodes for lithium-ion batteries.
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in situ measurements of stress evolution in Silicon thin films during electrochemical lithiation and delithiation
Journal of Power Sources, 2010Co-Authors: Vijay A Sethuraman, Michael J Chon, Maxwell Shimshak, Venkat Srinivasan, Pradeep R GuduruAbstract:We report in situ measurements of stress evolution in a Silicon thin-film Electrode during electrochemical lithiation and delithiation by using the multi-beam optical sensor (MOS) technique. Upon lithiation, due to substrate constraint, the Silicon Electrode initially undergoes elastic deformation, resulting in rapid rise of compressive stress. The Electrode begins to deform plastically at a compressive stress of ca. −1.75 GPa; subsequent lithiation results in continued plastic strain, dissipating mechanical energy. Upon delithiation, the Electrode first undergoes elastic straining in the opposite direction, leading to a tensile stress of ca. 1 GPa; subsequently, it deforms plastically during the rest of delithiation. The plastic flow stress evolves continuously with lithium concentration. Thus, mechanical energy is dissipated in plastic deformation during both lithiation and delithiation, and it can be calculated from the stress measurements; we show that it is comparable to the polarization loss. Upon current interruption, both the film stress and the Electrode potential relax with similar time constants, suggesting that stress contributes significantly to the chemical potential of lithiated Silicon.