RML Group is a leading high-performance engineering company delivering world-class solutions in motorsport and automotive.

They also specialize in EV technology for road and race applications utilizing their state-of-the-art energy storage design and manufacturing facility.

Problem: Minimise Variations in Battery Temperature

RML is developing a modular 48V battery concept for automotive and motorsport applications.

RML want to optimise the cooling of the battery pack to minimise variations in temperature across the pack which can negatively impact the performance and life of the pack.


CFD Analysis

RML asked Caepro to perform a CFD analysis of the current design of the battery pack to identify the cooling system efficiency.

A coupled thermal analysis was also required to determine the variation in cell temperatures across the module which drives the design for positioning cell thermistors in the module design.

Caepro have significant experience in performing thermal analysis for conventional internal combustion engines and electrified powertrains.

The analysis included the resistive heating of the busbar and interconnect along with the cell heat rejection for the complete duty cycle.

Assumptions were made on thermal gap resistance at the interfaces of the components where information was not readily available based on Caepro’s experience with thermal modelling of electrical components.

Design Recommendations

Based on the initial analysis Caepro were able to propose design changes to improve the cooling circuit efficiency and thermal performance of the modular battery system.

The reduction in the areas of stagnation (which was significant throughout the cooling circuit) should help to reduce the pressure drop across the circuit.

With increase in coolant velocities the same coolant mass flow rate should be able to increase the heat transfer coefficients.

The design changes should also better balance the battery temperatures and reduce the cell-to-cell temperature variation.


RML made the changes to the design and this was re-analysed.

The new design showed a reduction in cell-to-cell temperature variation by around 14%.

Duty cycle maximum temperatures were reduced by 11% and pressure drop was reduced by around 39%.


Client Feedback

“The analysis performed by Caepro was very helpful in guiding the design to optimise the battery cooling performance.

The quality of the analysis, reporting and design recommendations were excellent.

We were also impressed with the ease of interaction with the engineering team.

We look forward to using Caepro’s services again in design and analysis in other areas in the near future”.

Mark Way, Director of Engineering, RML

Can we help you?

If you think Caepro can help you with your current engineering requirements or you would like to know more about our company and services please send us an email at info@caepro.com and we’ll get back to you straight away.