Similar to the default Newman’s P2D model, the physics-based battery swelling model can also be solved in the E-Chem standalone mode. In this case, the following types of mechanical load can be modeled for the battery sandwich layer in Ansys Fluent:
External pressure exerted normal to the electrode layer
The effective mechanical pressure
is obtained as:
(19–78)
Total thickness change of the electrode layer
The effective mechanical pressure
is inversely calculated by the following equation to meet the target total
thickness change:
(19–79)
Effective stiffness of the electrode layer mounting
(for example, the battery case)The effective mechanical pressure
is inversely calculated by the following equation to meet the
stress-strain-relation under external stiffness:
(19–80)
In Equation 19–79 and Equation 19–80, the nomenclature used is the same as in Equation 19–72 and Equation 19–77. The left-hand side represents the total electrode deformation strain averaged over the sandwich layer, and the right-hand side represents the effective load strain.
Refer to Running the Standalone Echem Model in the Fluent User's Guide for more information.