Question about pybamm.lithium_ion.get_initial_stoichiometries()

[Weisserlinks]

Dear Pybamm team,
Recently I've been trying to do aging-simulation of the Samsung 35E battery. In order to calculate the capacity, I chose to use pybamm.lithium_ion.get_initial_stoichiometries() function to get the stoichiometry both in SOC=0 and 1 and then did the calculation: C_0 = (x_100 - x_0) * solution["Negative electrode capacity [A.h]"].data[0]. For unknown reasons there was a small "jump" of my results on some batteries as the picture attached shows. I managed to figure out that it was due to the sudden change of the variable 'x_100' ---- stoichiometry of negative electrode at SOC=1. Would anyone happen to know the reason?
Many thanks in advance :)

[valentinsulzer]

It looks like numerical error in the algebraic equation solve that is used to solve for x_100. Maybe a non-monotonic OCV? I'm planning on working on improving this solver and debugging tools around it

[Weisserlinks]

Thanks for your answer! I'm now avoiding this problem by simulating less cycles.