Copper and aluminium have carried heat out of electronics for a century. Graphene is the first material to beat both on the metric that matters in mobile, airborne and space hardware - conductivity per unit mass.
Five dimensions of comparison
| Dimension | Graphene plate | Copper | Aluminium |
|---|---|---|---|
| Through-thickness conductivity (W/m·K) | 1200 | ~400 | ~200 |
| Density (g/cm3) | ~1.5 | 8.9 | 2.7 |
| Weight at equal size | 1x | 6x | 1.8x |
| Corrosion resistance | Excellent | Oxidises readily | Moderate |
| Cost per unit thermal capability | Lowest | Highest | Low material cost, high mass cost |
When to choose graphene
Choose a graphene plate when mass matters (airborne, portable, satellite), when the heat source is a concentrated hot spot that needs to be spread before it reaches a cold plate, or when CTE matching against a ceramic package matters. The through-thickness conductivity is three times copper at a fraction of the density.
When to choose copper
Copper remains the right answer where thermal mass is an advantage (transient absorption), where high mechanical strength is needed, or where the part is a general structural component with a generous mass budget. Copper is also easier to solder and braze into legacy assemblies.
When to choose aluminium
Aluminium is the default for large, cost-sensitive structures. Its conductivity is modest, but it is cheap, easy to extrude and machine, and often the enclosure is aluminium anyway so the heat path is already there.
Three advantages of the Lenecold plate
- Conductivity per kilogram. 1200 W/m·K through-thickness at 1.5-4 g/cm³ - roughly 6x the specific conductivity of copper.
- Tunable CTE. 4-12 ppm/K can be matched to ceramics and composites, reducing solder and die-attach fatigue.
- Built to be stacked. The plate carries heat across the assembly while a 180 W/m·K pad crosses the gap - which is exactly how a stacked thermal path should be built.
Where the plate fits in a stack
The plate is a structural conductor, not a gap filler. In a high-power stack a 180 W/m·K pad crosses the gap between the die and the plate, and the plate carries the heat on to the cold plate or heatsink. Each layer does the job it is good at.