New Publication in “Journal of Materials Chemistry A”

Electrochemical reactions within Li-ion batteries occur far from equilibrium and are accompanied by considerable heterogeneity. The sequence and propagation of these phase transformations determine energy dissipation and the proportion of actively intercalating materials, which play a vital role in influencing characteristics such as cyclability, degradation, and hysteresis. …

Prof. Xu gave an invited talk in the 649. WE-Heraeus-Seminar “In-operando characterization of energy materials” in Bad Honnef, 23-27 Aug 2017. She spoke about “Multiphysics phase field modeling of electrode materials in Li-ion batteries”.

New Publication in “RSC Advances”

Lithium transport and phase separation in and across interconnected electrode particles are investigated in this paper. This paper signifies the influential role of particle size variation on battery performance with phase-separating electrodes. In this work, a model is developed which accounts for lithium transport in the particles, phase separation, and interface reactions across the particle network. …

New Publication in “Acta Mechanica”

The dynamic response of a pre-stretched elastomer membrane under electric loading was analysed. Thereby, two cases of voltage application, constant voltage and an incrementally increased voltage were regarded. The equation of motion (EOM) was derived from the Euler–Lagrange equation and the Rayleigh dissipation function. This allowed to include the influence of prestretch into the evolution equation of the viscous stretch. …

New Publication in “Continuum Mechanics and Thermodynamics”

A comprehensive study on a finite-deformation gradient crystal-plasticity model which has been derived based on Gurtin’s framework is carried out here. This systematic investigation on the different roles of governing components of the model represents the strength of this framework in the prediction of a wide range of hardening behaviors as well as rate-dependent and scalevariation responses in a single crystal. …

New Publication in “Physical Review Applied”

We perform a combined first-principles and micromagnetic study on the strain effects in Nd-Fe-B permanent magnets. First-principles calculations on Nd2Fe14B reveal that magnetocrystalline anisotropy (K) is insensitive to deformation along the c axis, and that a-b in-plane shrinkage is responsible for K reduction. The predicted K is more sensitive to lattice deformation than the previous phenomenological model suggests. …

New Publication in “Nature Communications”

A higher saturation magnetization obtained by an increased iron content is essential for yielding larger energy products in rare-earth Sm2Co17-type pinning-controlled permanent magnets. Here we present model magnets with an increased iron content based on a unique nanostructure and -chemical modification route using Fe, Cu, and Zr as dopants. …

Prof. Sarbajit Banerjee and his colleagues visited our group from June 25th to 29th, 2017. Prof. Banerjee also gave a presentation at the colloquium of the department on June 26th, 2017. We had an intense discussion about the coorperation of the modeling and experiments on the intelligent and energy materials.

New Publication in JOM

In order to simulate the diffusion of Li ions in SiOC nanocomposites, we developed a reaction-diffusion model for multiphase materials. This model extends existing models for single-phase diffusion through consideration of the ion transport across material interfaces. …

The event TU Darmstadt Day at Tongji University took place in Shanghai successfully on 19.05.2017. In the framework of TU Darmstadt Day, the bilateral workshop of Functional Materials also took place, colleagues have exchanged their current research results and discussed the possible future steps of research and collaboration in the field of materials science.