Discussion Forum

Dear COMSOL Users, I am new to COMSOL and just getting started with the Battery Module. In my lab, we are exploring how architecturing electrodes can be used to fabricate high energy density, high power electrodes.

I tried building a model of a simple 2D cathode with a channel in it, a separator, and an anode. I used the Battery and Fuel Cells: Li-ion Battery Physics(uses the Newman equations). I applied a current density boundary condition to the cathode and an electric ground to the anode. The current density is a discharge current. (Eventually I would like to lookat a full cycle/ discharge and charge). The separator equations were used in the separator region, the material for this regions is LiPF6. Both the anode and cathode are modeled as porous electrodes(using the time dependent formulation). The study is a time dependent study.

For now, I used LMO for the cathode and graphite for the anode- I chose this hoping I might be able to compare the input values with the Application Libraries module 1D Li ion isothermal battery- I used all their values for the electrodes (i.e. diffusion constant, electrical confuctivty, etc.) Just my battery architecture is different .

I don't trust the results I am obtaining they are showing a voltage drop of 0.3V. This does not make physical sense! DO any of you have any thoughts on what I could be doing wrong? I would really appreciate any thoughts or even advice on where to start with these simulations.

As I am new, I am still trying to figure out what input I should use! My feeling is there is some problem with how I am formulating the problem!

Thanks again in advance. I look forward to seeing what replies I recieve