BatteryDict Module

The module BatteryDict

BatteryDict is the GeoDict module to generate electrode material models and simulate the charge of Li-ion batteries.
For the latter, the BEST solver (Battery and Electrochemistry Simulation Tool) of the Fraunhofer Institute for Industrial Mathematics, ITWM has been integrated into GeoDict.
The charge curve at a user-chosen charging rate is obtained and compared to the corresponding equilibrium curve at a very slow charging rate. The curves are displayed in the simulation result summary. BatteryDict also analyzes the microstructure of battery materials and shows inactive regions in material and electrolyte.

The BatteryDict module contains:

  • BatteryDesigner - Battery modelling
  • BESTmicro - Battery-charging simulation
  • BESTmicroFFT - Battery-charging simulation

Concentration of Li-ions in an electrode during charging.

BatteryDict features

BatteryDesigner - Battery modelling

The BatteryDesigner produces battery materials with material models generated in GeoDict. The separation distance and the orientation of the electrodes can be specified to obtain the cell geometry, including the amount and location of all the components of the cell and the unconnected components, which reduce the energy density of the cell.

The following parameters and materials can be digitally defined and modified:

  • Anode material
  • Cathode material
  • Separator
  • Current collectors on anode and cathode side

BESTmicro - Battery-charging simulation

GeoDict with BESTMicro is a user-friendly, easy-to-use bridge between the structures modelled with GeoDict and the testing of their performance using the feature-rich BESTMicro (Battery and Electrochemistry Simulation Tool).
BESTMicro, already well known in the field of battery simulations, is being developed at the Fraunhofer ITWM for years. Uniting these two software-tools was a natural step after long years of parallel development.
As a result, many of the functionalities of BESTMicro can be used without leaving the comfortable environment of GeoDict.

BESTmicroFFT - Battery-charging simulation

BESTMicroFFT is a very fast algorithm for performing cell charging and discharging simulations. The domain sizes can be as large as needed to simulate the thickness of the real electrode.
As a result, the user obtains the charge and discharge curves, the electrical potential, and even the lithium concentrations for several charge states in all given materials. All these fields can be visualized in 3D.

Examples of BatteryDict applications

Improving lithium-ion batteries:

  • Checking for inactive material in the cell.
  • Running the simulations with several charge rates.
  • Estimating the efficiency of the battery by comparing the cell potential over state of charge to the open-circuit voltage.
  • Observing the changes in Li-ion concentration in each particle during charging.

Additional modules needed?

  • The GeoDict Base package is needed for basic functionality.
  • BatteryDict works on 3D (micro-)structure models that can either be a segmented 3D image (microCT-scan, FIB-SEM) imported with ImportGeo-VOL, or a 3D structure model created with GrainGeo, one of GeoDict modules for Digital Material Design.
  • BatteryDict can make use of the solver of ConductoDict to determine the diffusion coefficient within the materials
  • The GrainFind module might be useful to determine the grain sizes of granular structures in the battery materials.
  • PoroDict and MatDict might be interesting to analyze the geometric properties of pore space and solids in the battery model.