Hello Praveen,

You should remember that diffusion in Li-ion batteries has some differences if compared with the "traditional", Warburg-like "semi-infinite" diffusion.

Looking at your data, maybe it could be a good idea to go deep into lower frequencies (you can up to 1 mHz). Also you can increase the number of points per frequency decade to achieve better resolution of your data.

Also, try to use other diffusional elements such O and T, which are used for batteries. Take a look here: http://www.consultrsr.net/resources/eis/diffusion.htm

Hope it helps.

Hi Othon,

Thanks for your suggestion. My EIS tool can go only till 0.1Hz and only 6 points per decade. Those are the maximum possible features.

what model you have used to fit the above one

Priya Srivastava 2RC model, see pic

Dear Praveen Kumar Kuppusamy ,

Despite of nice fitting, I think your Equivalent circuit is not right, (from a Physics perspective)!

As I can see from your experimental data, your Warburg element should be considered as an Warburg open (Wo) connected in series to the Resistance (Rct or Rp) in second RC component (corresponding to the performance of Cathode during Discharge in low frequency).

Thus, even you have such a nice fitting, your experimental data does not support the equivalent Circuit and corresponded Electrochemical performance of the involved species !