Abstract : The mini-symposium addresses various aspects of modelling and simulation of electro-chemo-mechanical processes in batteries and fuel cells. It is aimed at scientists from academia and industry and focuses on the physical and mathematical fundamentals of the processes rather than the system level. Aspects such as model derivation at the microscopic level and its upscaling, model validation and model reduction are the focus of this mini-symposium. It covers contributions on lithium and sodium ion and redox flow batteries, solid oxide and polymer electrolyte fuel cells, among others.
Organizer(s) : Thomas Carraro, Manuel Landstorfer, Yosuke Komatsu
[01934] Li-Ion battery kinetics model validation of NMC 111 and Graphite
Format : Talk at Waseda University
Author(s) :
Robert Morasch (Technical University of Munich)
Bharatkumar Suthar (Indian Institute of Technology Bombay)
Hubert Gasteiger (Technical University of Munich)
Abstract : Understanding Li-Ion battery fundamentals is an important aspect when modelling Li-Ion batteries. The Doyle-Fuller-Newman model is often used as mathematical basis for such models, but rarely validated. Here we present an in-depth analysis of the kinetic behavior of NMC 111 and graphite using Electrochemical Impedance Spectroscopy. Measurements on thin electrodes allow an easy distinction of the kinetic resistance for either electrode without the influence of transport resistances.
[04354] Fluid–electrochemical-stress-coupled Simulation Method for SOFC Degradation Prediction
Format : Talk at Waseda University
Author(s) :
Mayu Muramatsu (Keio University)
Masami Sato (Tohoku University)
Reika Nomura (Tohoku University)
Kenjiro Terada (Tohoku University)
Yashiro Keiji (Tohoku University)
Tatsuya Kawada (Tohoku University)
Harumi Yokokawa (The University of Tokyo)
Abstract : To predict the mechanical degradation of solid oxide fuel cells (SOFCs) during operation, we have developed an analysis system for their electro-chemo-mechanical phenomena by incorporating general-purpose finite element analysis software. This simulation system also takes into account the effects of gas and heat distributions, also calculated by commercial software.
[02306] Modeling and State Estimation of Lithium-Ion Batteries under Long-Term Degradation Conditions in Aerospace Application
Format : Talk at Waseda University
Author(s) :
Linda Juliane Bolay (German Aerospace Center (DLR))
Abstract : The performance and durability of Li-ion batteries is impacted by various degradation mechanisms such as SEI growth. Here, we address the modeling and simulation of the batteries of the Japanese satellite REIMEI. We simulate SEI growth in a P2D and microstructure-resolved framework. The simulations are validated with in-flight data from JAXA. Furthermore, a multi-time-scale filter algorithm is applied to estimate the inner states of the battery by making use of the battery in-flight data.
[02922] Simulation of Chemo-Mechanically Coupled Battery Active Particles with Mechanical Constraints
Format : Talk at Waseda University
Author(s) :
Raphael Schoof (Karlsruhe Institute of Technology)
Giuseppe Fabian Castelli (Karlsruhe Institute of Technology)
Willy Dörfler (Karlsruhe Institute of Technology)
Abstract : During charging and discharging of lithium-ion batteries, large mechanical stresses can occur due to phase-separation or limited swelling area. A chemo-mechanically coupled model for cycling battery active particles with mechanical constraints is used to investigate the stress development within representative active particles. The combination of the primal-dual active set algorithm, interpreted as semismooth Newton method, and a spatial and temporal adaptive algorithm allows the efficient two- and three-dimensional numerical simulation and computationally intensive parameter regimes.
[03277] A Model Framework for Lithium Ion Intercalation Cells
Format : Talk at Waseda University
Author(s) :
Manuel Landstorfer (Weierstrass Institute for Applied Analysis and Stochastics (WIAS))
Alireza Selahi (Weierstrass Institute for Applied Analysis and Stochastics (WIAS))
Abstract : We present a model framework for Lithium-ion batteries based on non-equilibrium thermodynamics. It emphasizes thermodynamic consistency, especially for reaction rates and concentration-dependent diffusion coefficients. A coupled two-scale PDE system is derived using periodic homogenization. Numerical simulations are finally shown, predicting the cell voltage during cycling at different C-Rates. We compare single- and many-particle electrode models and discuss the impact of material functions, diffusion coefficients, and reaction rate models based on numerical simulations.
[02810] Asymptotic reduction of a model for mechanical stresses in cylindrical batteries
Format : Talk at Waseda University
Author(s) :
Jon Chapman (University of Oxford)
Robert Timms (University of Oxford)
Steven Psaltis (Queensland University of Technology)
Colin Please (University of Oxford)
Abstract : Macroscopic mechanical stresses in lithium-ion batteries are known to significantly affect the long-term degradation mechanisms. These stresses are created by expansion and contraction of the different parts of the structure, due both to thermal variations and lithiation state. Predicting the resulting stresses using numerical techniques is made difficult due to the small-scale geometry of current collectors, separator and regions of active material.
Here we use the methods of boundary layer analysis and homogenisation, exploiting the small-scale periodic structure of a spirally-wound cylindrical battery, to derive a reduced-order model to determine approximations to the resulting stresses.
[04382] Modeling Solid Oxide Fuel Cells based on Electrode Microstructure Information
Format : Talk at Waseda University
Author(s) :
Masashi Kishimoto (Kyoto University)
Hiroshi Iwai (Kyoto University)
Abstract : Understanding the effect of the porous microstructure of SOFC electrodes on the electrochemical performance is essential in predicting their macroscopic performance and thereby optimizing electrode microstructure. We present several numerical simulation models of SOFCs with quantitative information of the electrodes obtained by 3D imaging technique based on focused ion beam scanning electron microscope (FIB-SEM). Typical results of microscopic distribution within the electrodes and macroscopic performance, such as overpotential and impedance characteristics, are overviewed.
[03013] Exploring non-isothermal effects in all-vanadium redox flow batteries through advanced numerical models
Format : Talk at Waseda University
Author(s) :
Marcos Vera (Universidad Carlos III de Madrid)
Vanesa Muñoz-Perales (Universidad Carlos III de Madrid)
Santiago E. Ibáñez (Repsol)
Enrique García-Quismondo (IMDEA Energy)
Sabrina Berling (IMDEA Energy)
Jesús Palma (IMDEA Energy)
Abstract : Redox flow batteries are a promising electrochemical technology for large-scale stationary energy storage that still requires further development to increase its profitability and energy market penetration. Continuous macroscopic models enable the optimization of new architectures and operational strategies without extensive fabrication and experimental procedures. This work presents a non-isothermal two-dimensional steady-state model of a unit-cell all-vanadium redox flow battery. The model integrates state-of-the-art descriptions of the fundamental physical phenomena along with new features, such as local mass transfer coefficients for the active species, precise sulfuric acid dissociation kinetics, and experimentally determined electrochemical parameters and electrolyte properties. The model is validated at different states of charge, flow rates, and operating temperatures using polarization, conductivity, and open circuit voltage measurements. Then, the contribution of operating conditions to battery performance is studied by analyzing its separate effect on the various phenomena that affect cell performance, such as local pore mass transfer limitations, parasitic hydrogen evolution reactions, crossover, and self-discharge fluxes. After model calibration, a parametric study is carried out to explore the role of the operating temperature, deconvoluting the different contributions to cell heating and providing practical guidance about the thermal effects induced by operating conditions. The results reveal that i) increasing the cell temperature enhances species mass transfer but negatively affects activation losses, ii) the cell suffers higher overheating during charge than during discharge, and iii) cell heating increases proportionally with cell length. Lastly, we propose using asymmetric electrolyte temperatures as a performance improvement strategy for electrochemical storage systems hybridized with thermal energy storage. The resulting model is a reliable tool that can be used to assess the relevance of the coupled phenomena that take place simultaneously within the reaction cell. This vital information is critical to optimize cell components, reactor design and selecting optimal operating conditions.
01140 (3/3) : 5D @G404 [Chair: Manuel Landstorfer]
[04773] Electro-chemical based modelling of battery cells for automotive applications.
Format : Online Talk on Zoom
Author(s) :
Edwin Knobbe (BMW AG)
Abstract : This contribution presents challenges with respect to modelling and (numerical) simulations of the interaction of mechanics and electro-chemistry for applications in battery cell development. Some of the challenges will be explained by examples relevant for automotive applications. For instance: solid mechanics to model the swelling behavior of battery cells during cycling, fluid mechanics with detailed chemistry during a thermal event and modelling electro-chemical phenomena at the interface between an electrode and a solid electrolyte.
[02597] Analytical solution to a multilayer particle model for Li-ion cells under generic high current profiles
Format : Online Talk on Zoom
Author(s) :
Javid Piruzjam (Mercedes-Benz AG)
Lukas Rubacek (Mercedes-Benz AG)
Thomas Carraro (Helmut Schmidt University / UniBw Hamburg)
Abstract : Reduced order Li-ion battery models are widely used in applications such as state of charge estimation by electric vehicles’ battery management systems, or cell characterization. Among those models, Single Particle Model is a computationally inexpensive physics-based solution. However, neglecting the effect of the electrolyte dynamics on the cell performance, SPM can lead to large errors especially at high current applications. In this work, we propose an analytical solution to a single particle model including electrolyte dynamics (SPMe) which is applicable for a wide range of currents. The boundary conditions and source terms in all differential equations are time-varying, and a spherical multilayer diffusion scenario is also considered which allows modelling particles coating and degradation effect.
[05025] Microstructural resolved simulations of NVP-C electrodes for Sodium-ion batteries
Format : Talk at Waseda University
Author(s) :
Paul Maidl (German Aerospace Center)
Simon Hein (German Aerospace Center)
Timo Danner (German Aerospace Center)
Matthias Neumann (University Ulm)
Marcel Häringer (Karlsruher Institue of Technology )
Luca Schneider (Karlsruher Institue of Technology )
Werner Bauer (Karlsruher Institue of Technology )
Ingo Manke (Helmholtz-Zentrum Berlin)
Volker Schmidt (University Ulm)
Joachim R. Binder (Karlsruher Institue of Technology )
Arnulf Latz (German Aerospace Center)
Abstract : Sodium-ion batteries are a promising candidate for sustainable future energy storage technologies. Although they have some similarities with Lithium ion batteries, today's modelling and simulation techniques for Sodium-ion batteries is lacking behind their Lithium counterpart. One interesting material for both anode and cathode is NVP-C ($Na_3V_2(PO_4)_3$ with added carbon). In our contribution we show simulation approaches for virtual material characterization of its complex three-dimensional microstructure and its influence on cell performance.
[05164] Improving Lithium-ion Battery Models for Porous Secondary Particles: A Comparison of Homogenized and Microscopic 3D Models
Format : Talk at Waseda University
Author(s) :
Javid Piruzjam (Mercedes-Benz AG)
Phillip Gräfensteiner (Ulm University)
Matthias Neumann (Ulm University)
Lukas Rubacek (Mercedes-Benz AG)
Volker Schmidt (Ulm University)
Thomas Carraro (Helmut Schmidt University / UniBw Hamburg)
Abstract : We present a study on a homogenized model for porous secondary particles of lithium-ion batteries in comparison with microscopic 3D models. The 3D microstructures are based on FIB-SEM tomography, which provides high-resolution images of the secondary particles. Homogenized electrode-level models are widely used in battery applications due to their computational efficiency, e.g., in the electric vehicle industry. However, the accuracy of these models can be improved if the transport processes within the porous particles are considered, especially when complex microstructures are involved. Our investigation aims to improve the quantitative prediction of multiscale models. To perform a comprehensive study, we use digital twins to obtain adequate stochastic representations of the microstructure.
