Thermal Management Material Development for High Density Electric Batteries

Charging and discharging inefficiencies of spaceborne and airborne battery cell designs result in significant heat dissipation. A closely packed battery of these cells poses a heat removal problem. The efficient removal of this energy is critical in maintaining target operation temperatures. Thermal pyrolytic graphite (TPG) is a highly aligned crystalline graphite with an in-plane thermal conductivity of 1700 W/mK. Encapsulating TPG within a carbon fiber encapsulant results in a high conductivity (> 1000 W/mK), low mass density (< 2.0 g/cm3) material system. The isotropic in-plane conductivity of the TPG will increase the composite thermal performance by 300% over typical K1100/Polymer composites. In addition to high specific conductivity, the proposed material system can have tailored thermal expansion and stiffness properties. The objective of this Phase I program is to determine the feasibility of using the carbon fiber encapsulated TPG material in airborne and spaceborne battery structure designs through the development and evaluation of material samples. The program will establish, through sample evaluation, key design, fabrication, and performance characteristics.