Setting up multiple segments in Dualfoil.py
Dualfoil.py allows the user to set up multiple segments by entering lists in the Boundary
Conditions menu entries. Below is a list of descriptions for each parameter in the menu.
“Number of segments in this simulation:” This is where the user inputs how many different
sets of boundary conditions will be included in the following simulation.
All parameters after this point must be entered as comma delimited lists for more than one
specified segment. For example, if the number of segments desired is two, then each parameter
entry should have two values separated by a comma (see Fig. 1 below). The first value of each
list corresponds to the boundary conditions of the first segment, and the second set of values to
the boundary conditions of the second segment.
“Mode of segment(s)” Here the user enters what mode they want each segment to run in. This
entry should be a single integer from the list presented below the parameter.
“Segment current/potential/power/load:” This entry represents a current density in A/m2 for
modes -1, 1, and 2 where a positive entry will discharge the cell. For mode 0, this entry is a cell
potential in V. For mode -2, this entry is specified power in W/ m2. For mode -3, this entry is a
specified load in ohm-m2.
“Simulation time (min) OR potential cutoff (V):” For modes -3, -2, 0 and 1, this entry is the
simulation time for that segment in minutes. For modes -1 and 2, this entry is the potential cutoff
in V.
“Low voltage cutoff value (V):”
“High voltage cutoff value (V):”
“Internal resistance of foils, tabs, etc. (ohm-m2):”
An example scenario can be found on the following page.
While self-explanatory, these
parameters need to be specified for
every segment, even if they do not
change from segment to segment.
Figure 1: This setup will simulate a battery that runs 3 different segments. This battery will
discharge at 10 A/m2 for 10 minutes, then 5 A/m2 for 5 minutes, and then 15 A/m2 to a cutoff
potential of 2.8 V. The first two segments are designated as 1’s in the “Mode of segment(s)”
entry, and the third is designated as a 2. Thus, the first two segments will be galvanostatic for a
given time in minutes, and the third segment will be galvanostatic to a cutoff potential in V. For
all three segments, “Segment current/potential/power/load:” will be a current density. For the
first two segments, the “Simulation time (min) OR potential cutoff (V):” entry will represent a
simulation time in minutes, while the third value in the entry will correspond to a cutoff
potential, since the third mode was designated as a 2 (galvanostatic to a cutoff potential in V).
The rest of the entries were set to remain the same for all three segments, but note that three
values were still specified for each segment.