Get more out of your system with battery pack simulation

Battery pack simulation predicts how a pack of cells behaves in a system: voltage, current, temperature and state of charge over a duty cycle. Engineers use it to size cooling, set current limits and test control strategies before a prototype exists. Simulation-based development is much faster than building one prototype after another. You can also test far more comprehensively in simulation and so clearly reduce the probability of remaining errors in the current design. The pack model connects cells, thermal paths and control. Its cell model decides whether the result holds.

The pack model mostly multiplies and connects what the cell model delivers. If the cell voltage is wrong at high current or low temperature, every series connection repeats that error. The same applies to heat: if the heat generation of the cell is wrong, the temperatures of the whole pack are wrong. The inverter, the thermal management and the control read voltage and temperature. A wrong value therefore leads to wrong control decisions, not to a slightly wrong result. Simulations are often about the limit cases, and that is exactly where the cell limits the system. The cell model has to be accurate there. That is what Batemo Cell Models are built for, because other approaches do not work well enough at these limits.

No. An equivalent circuit model copies the terminal behavior with simple elements. Its structure does not match the physics, and nonlinearities are not handled properly. It reproduces the points it was fitted to and drifts elsewhere. In cold, high-power or aged conditions, the results of the simulation are simply wrong. That is dangerous in system development, because you can no longer rely on your simulations. Equivalent circuit models should therefore not be used in system development.

A battery thermal model computes how much heat a cell produces and how that heat spreads and leaves the pack. For system questions in the pack, the Batemo Cell Model is the right approach: it predicts the heat dissipation of the cell in every operating point, couples it to the electrical behavior in your system simulation and is accurate enough for almost every question. Only when the temperature inside a cell is strongly unbalanced do you need the Batemo Cube Model, which resolves local hot spots. That is not the standard case, because a good pack design aims at cells that are as thermally homogeneous as possible. The Cube Model is therefore for detailed studies. For a complex pack geometry with coolant flow, the models run in 3D fluid simulation.

Batemo Cell Models have built-in integration for MATLAB Simulink, MATLAB Simscape, Simcenter Amesim, AVL CRUISE M, AVL FIRE M, Elements and Hexagon Cradle CFD, and as an FMU they run in all common simulation tools.

Across 198 validated cells the median model deviation is 0.8 %, measured against validation experiments. Batemo backs its models with a guarantee: if you can show us another battery cell model that is more accurate, we will refund your money. We publish the accuracy of every model on its own cell page on this website, and for every model we provide Excel reports that show its accuracy under the validation conditions in detail.