Top Challenges faced during eV Battery Simulation

Challenge 1: Getting an accurate Duty cycle data in the concept phase.

It is usually difficult for designers to have accurate Duty cycle test data in the concept phase. This data can be derived based on 1D System Simulations but requires very good technical knowledge of how to model the drivetrain in the 1D system simulations.

 

Challenge 2: Accurately predicting current and/ or heat

                The current inside the battery depends greatly upon the chemical composition of the electrolyte, the Ion Flow and the anode/cathode materials. Most commercial CFD solvers are coming up with Electrochemical physics modules to simulate chemistry and Ion flow inside the battery. The evaluation of CFD results need prior experience and a solid understanding of electrochemistry. The output of this simulation will be the primary inputs to the battery thermal simulations. So any error in the output out of this simulation may lead to the wrong cumulated outputs.

 

Challenge 3: Building the model for CFD Simulations

Even though the geometry of individual battery cell may not be very complex when it comes to the battery module/pack the number of cells become very large. And the cooling passages available are significantly narrow because of space constraints. So, the CFD simulations need good amount of time, high end graphical hardware and modeling expertise to capture fluid cavities and model fluid with boundary layers in narrow gaps. A CHT model size of a battery pack may easily cross a cell count of 100Million.

 

 Challenge 4: Access to an HPC Cluster for Computation as well as Multi-CPU licenses for simulating transient duty cycles.

                The models for battery packs can be very large and need the best computational hardware to simulate CHT analysis. High end workstations are usually insufficient for the purpose and an HPC cluster with a minimum 96 cores is a must. This is followed by the requirement of multi-CPU CFD software licenses. 

 

  Challenge 5: Interpreting simulation results and providing engineering proposals to the designer based on the simulation

                Unavailability of test data for correlation of simulation results might be one of the biggest hindrances that exist because most EVs are still in development phase. This makes it necessary to have very good domain knowledge & engineering knowhow   to be able to interpret the results of the simulation.