#Thermal Modelling

Battery pack performances are widely affected by the temperature of the cells. It is basically all related to their chemical and physical nature. Moreover, cell temperature relies on several factors such as cell internal resistance and cell heat exchange.

An accurate battery pack thermal model implies a deep knowledge on thermo and fluid dynamics of the system components, not only inside the battery but also in all the sub-systems working with the heat transfer medium.

The figure below shows the results of an experiments carried out during our validation activities of a racing electric powertrain with a liquid cooled battery pack. Cell and coolant temperatures are modeled with a maximum error of ±1.5°C.

Model inputs:

• battery cell thermal model calibration;
• vehicle speed;
• electric motor torque;
• thermal management system (air cooling, heat pumps or customer based cooling system).

The model is able to simulate the temperature of each cell inside the battery pack, keeping the computational effort low, and allowing the use of the model even in Real-Time applications. The model is flexible and easily tunable to cover the whole range of thermal management solutions.

#Voltage Modelling

Compact models with accurate results is the main goal we aim to accomplish.

In this case, a brief comparison between simulated battery pack voltage and State of Charge with experimental data is shown. Our battery pack model is an easly tunable model that can be used to simulate the electrical performances of HV battery packs composed with different Li-ion cell types.

Thanks to several calibration activities, our model allows us to simulate the battery pack voltage with a relative error lower than 1% with respect to the experimental data and the battery State of Charge with an absolute error even lower than 1%.

The variety of applications in which the model has been deployed enables us to check simulations reliability and precision, verifying the goodness of the results in 800V automotive powertrains architectures and many other.

What distinguishes us from existing solutions:

• Precision and flexibility;
• Complete emulation of electrical and thermal flows;
• Ability to drive any power supply on the market.