"uuid","repository link","title","author","contributor","publication year","abstract","subject topic","language","publication type","publisher","isbn","issn","patent","patent status","bibliographic note","access restriction","embargo date","faculty","department","research group","programme","project","coordinates"
"uuid:e72816bd-e344-4c8d-acf8-cf60bb90d3b3","http://resolver.tudelft.nl/uuid:e72816bd-e344-4c8d-acf8-cf60bb90d3b3","Tensorial effective transport properties of Li-ion battery separators elucidated by computational multiscale modeling","Zhuo, M. (TU Delft Applied Mechanics); Grazioli, D. (Università degli Studi di Padova); Simone, A. (TU Delft Applied Mechanics; Università degli Studi di Padova)","","2021","Existing battery modeling works have limitations in addressing the dependence of transport properties on local field variations and characterizing the response of anisotropic media. These limitations are tackled by means of a nested finite element (FE2) multiscale framework in which microscale simulations are employed to comprehensively characterize an anisotropic medium (macroscale). The approach is applied to the numerical simulation of transport processes in lithium ion battery separators. From the microscale solution, homogenized fluxes and their dependence on the downscaled macroscale variables are upscaled, thereby replacing otherwise assumed macroscale constitutive laws. The tensorial nature of macroscale effective transport properties stems from the numerical treatment. The proposed approach is verified against full-scale simulations. Several numerical examples are used to demonstrate the perils associated with accepted procedures, leading in some cases to severe discrepancies in the prediction of field quantities (from differences in the potential drop across the separator of about 27% for a fixed microstructure to more than 100% in the case of an evolving microstructure). Despite the use of simplified assumptions (e.g., synthetic microstructures), the numerical results demonstrate the importance of a tensorial description of transport properties in the modeling of battery processes.","Computational homogenization; Concentration-dependent transport property; Ionic transport in lithium ion battery separators; Multiscale battery component modeling; Time-evolving microstructure","en","journal article","","","","","","","","","","","Applied Mechanics","","",""
"uuid:4157736f-73ca-41e5-8c10-ecaee26256ff","http://resolver.tudelft.nl/uuid:4157736f-73ca-41e5-8c10-ecaee26256ff","Electrochemical-mechanical modeling of solid polymer electrolytes: Stress development and non-uniform electric current density in trench geometry microbatteries","Grazioli, D. (TU Delft Applied Mechanics); Zadin, Vahur (University of Tartu); Brandell, Daniel (Uppsala University); Simone, A. (TU Delft Applied Mechanics; Università degli Studi di Padova)","","2019","We study the effect of mechanical stresses arising in solid polymer electrolytes (SPEs) on the electrochemical performance of lithium-ion (Li-ion) solid-state batteries. Time-dependent finite element analyses of interdigitated plate cells during a discharge process are performed with a constitutive model that couples ionic conduction within the SPE with its deformation field. Due to the coupled nature of the processes taking place in the SPE, the non-uniform ionic concentration profiles that develop during the discharge process induce stresses and deformations within the SPE; at the same time the mechanical loads applied to the cell affect the charge conduction path. Results of a parametric study show that stresses induced by ionic redistribution favor ionic transport and enhance cell conductivity—up to a 15% increase compared to the solution obtained with a purely electrochemical model. We observe that, when the contribution of the mechanical stresses is included in the simulations, the localization of the electric current density at the top of the electrode plates is more pronounced compared to the purely electrochemical model. This suggests that electrode utilization, a limiting factor for the design of three-dimensional battery architectures, depends on the stress field that develops in the SPE. The stress level is indeed significant, and mechanical failure of the polymer might occur during service.","Battery performance; Electrochemical-mechanical coupling; Non-uniform electric current density; Solid polymer electrolytes; Trench geometry microbattery","en","journal article","","","","","","","","","","","Applied Mechanics","","",""
"uuid:2b4daa77-9394-4187-bad9-bb786f3cab8a","http://resolver.tudelft.nl/uuid:2b4daa77-9394-4187-bad9-bb786f3cab8a","Electrochemical-mechanical modeling of solid polymer electrolytes: Impact of mechanical stresses on Li-ion battery performance","Grazioli, D. (TU Delft Applied Mechanics); Verners, O. (TU Delft Applied Mechanics); Zadin, Vahur (University of Tartu); Brandell, Daniel (Uppsala University); Simone, A. (TU Delft Applied Mechanics; Università degli Studi di Padova)","","2019","We analyze the effects of mechanical stresses arising in a solid polymer electrolyte (SPE) on the electrochemical performance of the electrolyte component of a lithium ion battery. The SPE is modeled with a coupled ionic conduction-deformation model that allows to investigate the effect of mechanical stresses induced by the redistribution of ions. The analytical solution is determined for a uniform planar cell operating under galvanostatic conditions with and without externally induced deformations. The roles of the polymer stiffness, internally-induced stresses, and thickness of the SPE layer are investigated. The results show that the predictions of the coupled model can strongly deviate from those obtained with an electrochemical model—up to +38% in terms of electrostatic potential difference across the electrolyte layer—depending on the combination of material properties and geometrical features. The predicted stress level in the SPE is considerable as it exceeds the threshold experimentally detected for irreversible deformation or fracture to occur in cells not subjected to external loading. We show that stresses induced by external solicitations can reduce the concentration gradient of ions across the electrolyte thickness and prevent salt depletion at the electrode-electrolyte interface.","Battery performance; Electrochemical-mechanical coupling; Mechanical properties; Partial molar volume; Solid polymer electrolytes","en","journal article","","","","","","","","","","","Applied Mechanics","","",""
"uuid:7014198e-bbb9-44c6-b499-97772869147f","http://resolver.tudelft.nl/uuid:7014198e-bbb9-44c6-b499-97772869147f","Characterization of the structural response of a lithiated SiO2 / Si interface: A reactive molecular dynamics study","Verners, O. (TU Delft Applied Mechanics); Simone, A. (TU Delft Applied Mechanics; Università degli Studi di Padova)","","2019","We report the results of a computational study regarding the mechanical properties of a lithiated Si/SiO2 interface using reactive molecular dynamics. The study is motivated by an intended application of SiO2-coated Si
nanotubes as fibers in structural batteries with a fiber-reinforced composite architecture while serving as anodes. According to the results, main failure properties due to partly irreversible bond breakage during mechanical deformation are identified, indicating agreement with bond energy/bond order based estimates. Microscopic failure properties are also identified and interpreted in view of the observed processes of bonding degradation. In particular, the effect of Li distribution on the shear deformation response is evaluated as significant.","Composite cathode; Molecular dynamics; Silicon; Silicon oxide; Structural battery","en","journal article","","","","","","","","","","","Applied Mechanics","","",""