Discussion Forum

Hello,

I am attempting to create a 1D model for an NCA type battery. To do this i have tried to set up a similar 1D electrochemical model to the isothermal tutorial one on the tutorial section of the Comsol website. There are some parameter values i have not yet changed from the old chemistry to the new one, but i think this isn't causing my issue.

I have created my geometry, imported the materials (applying only the electrolyte to the geometry at first) and then applied my electrode materials to each porous electrode. I then applied BC's of ground at the negative electrode outermost point, and a cell current density at the positive electrode outermost point, as well as initial conditions that are essentially identical to the tutorials one (a step function that charges for 2000s, 300s break and then 2000s discharge).

I then try to run the model and find there is no insertion of current into my system, all my plots remain constant and the model runs extremely quickly.

I believe the issue is somewhere within my porous electrodes (PE's): probably in the porous electrode reaction sections: as it stands i have both of these set for c = Insertion particle concentration. I have the rest of the PE settings for c = 0.

Within the porous electrode nodes there are many sections to input temperature and concentration, what is the difference between say: the concentration within the particle intercalation section and the porous electrode reaction section? should different values of c be used for each part? Lastly are there any sections that should have a concentration of zero? (since i would be looking at the change in concentration over time causing a change in voltage)

Thank you for any assistance, if you need any more information please let me know and i can provide it.