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The parameterization of a physico-chemical model constitutes a critical part in model development. Conclusions about the internal state of a battery can only be drawn if a correct set of material parameters is provided for the material combination under consideration. In this work, parameters to fully parameterize a physico-chemical model for a 7.5 Ah cell produced by Kokam are determined and are compared with existing literature values. The paper presents parameter values and procedures to determine the parameters. Cells were opened under argon atmosphere and the geometrical data were measured. Hg-porosimetry was conducted to determine porosity, particle radius as well as tortuosity of the electrodes and the separator. Conductivity and diffusion constants of the electrolyte as well as the electronic conductivity of the active material were measured detecting the voltage response to a dc current. Physico-chemical models are based on fundamental equations describing migration and diffusion processes as well as intercalation kinetics. They can be used to gain understanding of internal processes of batteries and to optimize material development. Several papers have been published developing physico-chemical simulation models that are based on the work of Newman and Tiedemann 1975, 1 amongst others. 2-6However, one crucial part of physico-chemical models is the model parameterization. Especially if conclusions about the internal state of the battery are drawn, it is of utmost importance to choose the right parameters for the materials under consideration. To the knowledge of the authors no work exists where a simulation model was completely parameterized using the geometric data and the parameters of the materials of one commercial cell in total. In most works dealing with physico-chemical models, values from supplementary literature sources were used; parameters were fitted or even guessed, e.g. [2][3][4][5][6] There are publications focusing on the determination of certain parameters for certain material combinations. Park et al. 7 for example gathered diffusion constants as well as conductivities investigated for different materials used in lithium-ion batteries in literature. Several authors also determined exchange currents for graphite materials. 8-11The problem here is that these parameters are usually not measured with the purpose to parameterize a battery model. This leads to measurement setups and finally to parameters that are not applicable in battery models. The exchange current, for example, is usually not scaled with the active surface area, which makes a transfer to a material with a different surface structure impossible. Another example is the determination of the electronic conductivity of active materials. The conductivity in literature is usually not measured for a whole electrode setup, including the filler, binder and porous structure. This makes it difficult to apply these values in models.Furthermore, there are parameters that have (to the knowledge of the authors) not yet been investigated ...

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To draw reliable conclusions about the internal state of a lithium-ion battery or about ageing processes using physico-chemical models, the determination of the correct set of input parameters is crucial. In the first part of this publication, the complete set of material parameters for model parameterization has been determined by experiments for a 7.5 Ah cell produced by Kokam. In this part of the publication, the measured set of parameters is incorporated into a physico-chemical model. Model results are compared to validation test results conducted on the Kokam cell. The influence of current rate and temperature is considered as well as a comparison with pulse tests is shown. It is discussed to which extent material parameters obtained by experimental investigation of laboratory coin cells can be transferred to commercial cells of the same material. The validity of physico-chemical models to describe cells is shown.

Physico-chemical models are key for a successful use of lithium-ion batteries, especially under extreme conditions. For correctly simulating of the internal battery states and battery aging a suitable set of material properties is needed. This work presents methods to extract these parameters from commercial cells and demonstrates them analyzing a high-power prismatic cell. In a first step, the electrolyte analysis is described, followed by an examination of the active material. The composition as well as the porous structure are measured using optical emission spectroscopy and Hg-porosimetry. To determine the electrochemical properties of the electrode materials, coin cells with lithium as counter electrode are build. With these test cells, open circuit voltage curves and galvanostatic intermittent titration technique measurements are performed to determine the electrode balancing as well as the diffusion constants of the active material. Electrochemical impedance spectroscopy experiments on the full cell are used to determine the charge transfer. In the second part of this paper, a determination of the thermal parameters as well as a validation for the complete parameterization are described.