The innovation proposed in this STTR program is a high temperature membrane to increase the efficiency and power density of PEM fuel cells. The NASA application is newly emerging electric aircraft propulsion systems. The proposed membrane is based on novel proton conducting polymeric materials that will not require humidification or the use of leachable dopants to enhance proton transport. Operation of fuel cells at temperatures > 150 ?C will facilitate heat and water management, increase the current density, and reduce the over-potentials for hydrogen oxidation and oxygen reduction. These advantages will translate to lower power system weight for propulsion applications through reduced fuel cell system size and improved fuel economy. The high temperature membranes will be based on new polymer materials recently discovered at the University of Michigan (UM). In this program T/J Technologies will collaborate with UM to transfer this technology into fuel cell applications through developing blends or copolymers designed to improve fuel cell performance. T/J Technologies will modify casting and fabrication methods for the new membrane materials. The overall goal of phase I is to demonstrate a novel membrane that is mechanically, thermally and chemically robust at >150 ?C and attains a proton conductivity > 0.1 S/cm2.