27/09/2026
Is PCM or Silicone Potting Really the Answer to Battery Thermal Management?
When a battery pack starts getting hot, the obvious question is usually: How do we get the heat out?
That is where solutions such as PCM, silicon potting, thermal interface materials and cooling systems come into the discussion. They all have a role in managing the heat generated inside a battery pack.
But there is a more fundamental question that should come before that:
Why is the battery generating that much heat in the first place?
The heat generated inside a cell is influenced by its electrical resistance and the current flowing through it. A basic relationship is:
Q̇ = I²R
So, assuming resistance remains constant, doubling current increases resistive heat generation four times.
But in a real battery, resistance does not remain constant. Cell characteristics, temperature, SOC and the actual current profile all influence how the cell behaves.
And the current profile is rarely steady. A vehicle can move from cruising to acceleration, climbing, regeneration and repeated high-load events within the same drive cycle. Two battery packs with similar capacity can therefore experience very different thermal behaviour depending on the application.
This is why we think thermal management should not begin with the question of which material will dissipate the heat.
It should begin much earlier, with the cell.
The choice of cell, its behaviour under the expected load, the electrical architecture and the way current is distributed through the pack all influence the amount of heat that eventually reaches the thermal management system.
By the time we are discussing PCM or potting, we are already dealing with heat that has been generated.
Managing that heat is important. But understanding why it is being generated is where the deeper engineering begins.
That is why thermal engineering, in our view, is not a feature added to a finished battery pack. It is something that has to be considered from cell selection through pack architecture and actual application load.
At Redon, we don't look at thermal management simply as a way of getting heat out of the pack.
We look deeper, at the cell-level behaviour that creates the thermal problem in the first place.
