Exploring the Impact of Cell Orientation on Surface Cooling for Prismatic Battery Cell Testing
- Kelly Martin
- Jun 18
- 3 min read
Does the orientation of a prismatic cell matter when battery cell testing to mimic real-world conditions? We have found that it does.
As battery technology advances, the need for performance, characteristisation and storage testing for battery cells that closely replicates real-world applications is increasing. With the market leaning towards the use of prismatic cells, particularly in Electric vehicles (EVs), ensuring the cell will behave as expected in situ is an essential part of the battery development process.
Prismatic cells are typically surface-cooled when used in real world scenarios, and our lab has observed a growing demand for testing methods that align with this cooling approach. Thus we have been investigating the best methods for replicating the conditions a battery may be used in.
Effective thermal management is essential for battery performance and longevity; as such careful consideration is given to cooling loop flow rates and temperatures. Orientation of the cooling plate in relation to the cell also has an impact on cooling performance.
Our investigation
To quantify the impact of surface cooling orientation, we performed a controlled experiment on a 314Ah LFP prismatic cell, testing two distinct configurations. In the first configuration, the cooling plate was applied to the base edge of the cell. In the second configuration, the cooling plate was applied to the side edge. Each test was conducted over five hours to evaluate the thermal performance measured. The cooling plate was set to -30°C and the test was performed at 23°C ambient temperature.
Cooling Plate | Size: 305 x 178 x 15mm (LxWxH) Material: Aluminium |
Prismatic cell | 314Ah LFP prismatic cell Size: 174 x 72 x 205mm (LxWxH) |
Results
The results showed a significant difference in cooling performance between the two orientations. The side edge cooled cell cooled more quickly as seen in the figure below. It reached thermal equilibrium by 5 hours, whereas the base edge cooled cell was still cooling at this point. Additionally, the temperature gradient across the side edge cooled cell was lower during the cooling process, indicating more efficient and even heat dissipation.
These findings highlight the impact of internal cell geometry on cooling effectiveness. The current collectors conduct heat the best inside a cell. As seen in the figure below, due to the internal structure of the cell, the current collector may be closer to the side of the cell than to the base (see red arrows), while also present a larger area of contact for heat conduction. Hence, the orientation of the cooling surface in relation to the cell internal geometry directly affects heat transfer efficiency. Therefore, optimising cooling performance requires not only enhancing cooling capacity but also strategically managing where heat is extracted from the cell.
Refining surface cooling techniques for prismatic cells has significant implications for battery performance and lifespan. Proper thermal management ensures stable operating conditions, leading to predictable battery behaviour and improved efficiency. Additionally, reducing localized overheating minimizes cell degradation, thereby extending the operational life of the battery pack.
Cognition Energy: How we can help with battery cell testing
Interested in mimicking real-world scenarios in your next project through surface cooled testing?
Surface-cooled testing with CellPod Flow offers a practical way to replicate real-world conditions in a controlled environment. With complete flexibility, each project is bespoke including the cell size & chemistries and the types of tests run.
For more information on CellPod Flow Services click here: