Learning Forum

[Evan Sandoval]

Hello,

 

I am part of an FSAE electric team, and we are interested in using Ansys Fluent to model our battery throughout and endurance race (operating between 25degC and 60degC for about 10-20 minutes). The user manual says to that HPPC data can be inputted into the parameter estimation tool to get an estimate for internal resistances/capacitances, however the Battery Modeling course in the Ansys learning hub states that this is only accurate at one operating point. My main questions are:

• If we collect our HPPC data at various temperatures/SOC's, does Ansys create a lookup table for the different operating points? If so, how reliable are Ansys's interpolations/extrapolations of these operating points? Ideally, we'd have internal battery parameters as functions of SOC and temperature.
• I've noticed mention of a "state-space model" crafted from Electrochemical Impedance Spectroscopy data. Is this relevant to our use case for modeling various operating conditions?

Thank you for your help!

[Murari Iyengar]

Hi,

 ECM model is a linear model, so it calculates parameters at a single operating point and then interpolates/extrapolates for other operating points. Considering your HPPC test is done correctly, Fluent should be able to identify parameters accurately. Once this is done, Fluent is quite robust and accurate in providing results at various operating points and boundary conditions. We have done numerous tests to confirm this so, I can assure you of Fluent's reliability is this domain. 

You don't require the state-space model for this application, although it can be an alternative. As mentioned above, using HPPC data and Fluent's parameter estimation tool, Fluent can accurately calculate at various operating points.