An interesting thing is discovered that the newly added demo "capacity fade.mph" in 4.3a was deleted in 4.3b for unkonwn reason.
The capacity fade model was established by referreing to these two papers:
1. P. Ramadass, B. Haran, P. Gomadam, R. White, and B. Popov, “Development of
First Principles Capacity Fade Model for Li-Ion Cells,” Journal of the Electrochemical
Society, vol. 151, no. 2, pp A196–A203, 2004.
2. G. Ning, R. White, B. Popov. “A generalized cycle life model of rechargeable Li-ion
batteries”, Electrochimica Acta, vol 51, 2012-2022 (2006).
Most settings in the demo is the same as the models in the papers, except "the exchage current density of side reaction i0_side".
In the papers, i0_side was set to constant with typical value of 1.5e-6 [A/m^2].
However, in the demo of comsol 4.3a, i0_side was regarded as a varible of local current density of the main lithium intercalation (Jn). (Page 2 of models.bfc.capacity_fade.pdf)
This fundamental difference would lead to distinct simulation results.
I am very intereting if there is any argument for comsol to relate i0_side to Jn?
In fact, the simulation results appear more reasonable with Jn-related i0_side than constant i0_side. But, after refering to more than 20 papers, I have not find any phsical-based evidence to support the assumption that the i0_side is related to Jn.
The capacity fade model was established by referreing to these two papers:
1. P. Ramadass, B. Haran, P. Gomadam, R. White, and B. Popov, “Development of
First Principles Capacity Fade Model for Li-Ion Cells,” Journal of the Electrochemical
Society, vol. 151, no. 2, pp A196–A203, 2004.
2. G. Ning, R. White, B. Popov. “A generalized cycle life model of rechargeable Li-ion
batteries”, Electrochimica Acta, vol 51, 2012-2022 (2006).
Most settings in the demo is the same as the models in the papers, except "the exchage current density of side reaction i0_side".
In the papers, i0_side was set to constant with typical value of 1.5e-6 [A/m^2].
However, in the demo of comsol 4.3a, i0_side was regarded as a varible of local current density of the main lithium intercalation (Jn). (Page 2 of models.bfc.capacity_fade.pdf)
This fundamental difference would lead to distinct simulation results.
I am very intereting if there is any argument for comsol to relate i0_side to Jn?
In fact, the simulation results appear more reasonable with Jn-related i0_side than constant i0_side. But, after refering to more than 20 papers, I have not find any phsical-based evidence to support the assumption that the i0_side is related to Jn.