The input for a degradation simulation is the lithium concentration at the start and the end of a charging simulation. A previously run charging simulation with Charge Battery or Charge Electrode is therefore required before a degradation simulation can be run. With the Input Mode, define how the results of the charging simulation are provided for the expansion simulation.

Select Load from BatteryDict Results (*.gdr) to choose a charging simulation result file. Browse to the result file and choose the simulation step that you want to use as initial and final step for the degradation simulation.

GeoDict verifies if the battery currently in memory matches the selected result file. If a match is found, it will be displayed in green below the .cap files chosen as the initial and final steps. If a different structure is currently loaded, a warning is displayed in red.

Check Use intermediate Battery solution files (*.cap) to use all intermediate *.cap files between initial step and final step in the simulation.

Select Choose *.cap Files as Input Mode to define the .cap file directly. Browse to the .cap file with the lithium concentration for initial and final step of the expansion simulation. Make sure that the structure currently in memory fits to the selected .cap files.

In the upper right part of the dialog, choose the Experiment Conditions.

Since GeoDict 2025 you can simulate external mechanical load in the charging direction. This way you can analyze which amount of load leads to cracks and scratches in the battery microstructure. This is useful for solid state batteries, which are always operated under an external stack pressure or for cells confined in a battery pack. Select the Load Type X-Direction to be Stress or Strain. Then prescribe the compressive Stress in MPa (mega pascal) or the applied Strain in % in X-direction, which is the charging direction. Note that applying stress of 0 MPa is equivalent with setting the load type in X-direction to free in previous GeoDict releases. For confined boundary conditions in X-direction set the Strain to 0%.

For the tangential coordinate directions, define if the cell can expand Free in these coordinate directions, or if it cannot expand at all (Confined). Chose Mixed, when the cell can only expand in one direction.

Additionally, define the Number of Steps for the simulation. The number of steps defines the number of intermediate steps in the computation of the expansion. Either the whole concentration difference between initial and final step is applied in one step, or it is divided linearly and applied in several steps. If Use intermediate Battery solution files (*.cap) is checked, the number of steps defined is applied between all intermediate .cap files available.

Enable Object Tracking to keep object indices in the deformation simulation. This allows for the identification of the deformation of each individual object in the simulation. If the structure considered contains analytic object information, the .g32 file with object indices can be created from this analytic information,

or a previously created *.g32 file can be selected.

Finally, select the boundary conditions for the structure in the simulation. Use Periodic if the structure is periodic in all coordinate directions, Symmetric if it is not. Mixed boundary conditions are not available so far in BatteryDict-Degradation.