Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

"In Battery Current Distribution" singularity when modelling Charge-Discharge cycling (with constant voltage charging)

Please login with a confirmed email address before reporting spam

Hello,

I'm very new to modeling in general, and COMSOL in particular, so I'm having difficulty troubleshooting this particular issue.

I have made a simple charge-discharge model based on the li_battery_tutorial_2d (2D test copy.mph file attached), and it works without issues, it will perform as many cycles as I want and terminate when told.

However then I modified the geometry and materials to reflect a real LFP cell cross-section (2D test LFP copy.mph attached). Now it throws up a singularity error in the current distribution calculation when getting close to the voltage cutoff, specifically:

And

I enabled the automatic mesh refinement in the Initialisation and reduced the Tolerance Factor in the Absolute Tolerance of the Time-Dependent Solver, but that doesn't seem to have much effect aside from making the solution take longer until running into the same issue.

I just can't see where exactly is the core of the issue, why do the two behave so differently. Judging by the mesh refinement, the problem is with the Positive Electrode, but I honestly can't tell why exactly.



0 Replies Last Post Sep 20, 2024, 8:18 a.m. EDT
COMSOL Moderator

Hello Daniel Reinowski

Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.

If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.