[kimsw0103]

I am investigating lithium ion batteries using ANSYS.
My previous research was effect of phase transformation of micro size particle on mechanical stress. The important thing was phase transformation.
I use LiFePO4 as a cathode material.
During discharging process, lithium ion move from anode to cathode, and it cause phase transformation from FePO4 to LiFePO4.
FePO4 and LiFePO4 have totally different material properties. So, I use temperature dependent material properties (fig1). As you can see in fig1, I assumed that before discharging(FePO4), temperature is 0C and after discharging(LiFePO4), temperature will be 1C. It is the way i could simulate phase transformation according to the lithium insertion.
However, the model i developed did not considered effect of temperature since temperature is used to simulate phase transformation.

The next objective is to consider phase transformation and effect of temperature (thermal expansion) at the same time. To do this, I need to use "something (not temperature)" dependent material properties. I need help at this point!!!!!!!!!!!!!!!!! My idea is particle concentration. When small particle concentration, has material properties of FePO4. After accumulating (discharging), the particle concentration will increase and it has material properties of LiFePO4. Is it possible to do like this???

The second question is lithium ion concentration distribution. I am attaching the figure in the dissertation ch5 (http://etd.lib.msu.edu/islandora/obj...tream/OBJ/view). He did lithium concentration distribution in the electrode using COMSOL. Is it possible to simulate like this with ANSYS? And I also want to change material properties according to the concentration.

The last thing i want to do is cycle life of batteries.
To do this, I need to change the material properties change after specific cycle.... I am still thinking how to simulate.
Please give me any comments for cycle life of batteries.