Discussion Forum

%%%%% update 1:20130903 00:57 %%%%%
I have made a mistake.
The volume fraction and diffusion coefficient on both sides of boundary 3 may not be the same,
so there is sudden change in the gradient of electrolyte salt concentration.

Sorry to propose this stupid question.

%%%%% update 1:20130903 00:50 %%%%%
I may have made ​​a mistake in the original posts.
Please let me check it.

%%%%% Original posts %%%%%

In the demo "capacity fade.mph" in 4.3a, the electrolyte salt concentration is continuous in domanin 2 (Negative electrode), domain 3(Separator), domain 4(Positive electrode).
But its flux is not continous in boundary 3 and 4, which link the three domain. This can be seen from the simulation results by downloading attached file or clicking the following seb albums address:

o6i1gw.bay.livefilestore.com/y2preQpl7xXbSJIg1wuTk2wLwFnyRawPsuTO8nHSAe7pPLfdV4ASWeuNpjJsTvdNMxDe2e6hUMQ-grQF09UNUb5_cnsQmKAPtSfdHtJJkcynuk/comsol_2.jpg?psid=1

The "capacity fade.mph" was established by referreing to reference [1], which didn't explicitly discuss the flux continuity problem on electrolyte salt concentration.
The reference [2], which is more authoritative, believed that the flux of electrolyte salt concentration c_l is continous between negative electrode and separator and between positive electrode and separator. (see fig.3 of reference [2]).
The reference [3] was also claiming the flux continuty by Eq.(8) and Eq.(9).

My questions are:
1. How the flux was determined, if it was not explicitly defined in "capacity fade.mph" or other battery demos.
2. How to make sure the flux is continous in this demo?

Reference:
[1] Development of First Principles Capacity Fade Model for Li-Ion Cells
[2] Thomas F. Fuller,* Marc Doyle,* and John Newman. Simulation and Optimization of the Dual LithiumIon Insertion Cell.
[3] NALIN A. CHATURVEDI,REINHARDT KLEIN,JAKE CHRISTENSEN,JASIM AHMED, andALEKSANDAR KOJIC. Algorithms for advanced battery management systems.