AvCarb EP40 Gas Diffusion substrates are unparalleled in their ability to meet the rigorous demands of the fuel cell, including platinum catalyst and functional layer support, effective transport of gases and liquids, and conduction of heat and electricity. Moreover AvCarb EP40 substrates are highly durable, both chemically and mechanically.

AvCarb EP40 is the base substrate used in the gas diffusion layers: GDS3215, GDS3250, and GDS3260.

AvCarb Carbon Papers Properties Sheet

Gas Diffusion Layer Properties
Material Type	Carbon Paper Substrate
Nominal Thickness	.200 mm (200 microns) (@ 1psi / 0.7 N/cm²)
X-Nominal Thickness (@ 7.3psi / 5.1 N/cm²)	.190 mm (190 microns) (@ 7.3psi / 5.1 N/cm²)
Bulk Density	0.20 g/cm3 (@ 0.69 N/cm3 / 1psi)
Break Strength machine direction	5.0 MPa
Break Strength cross machine direction	3.5 MPa
Basis Weight	36 g/m3
Compressibility	14.0% ((22N - 113N)/22 x 100%)
Stiffness machine direction	9.5 Taber
Stiffness cross machine direction	3.5 Taber
Air Permeability (through-plane)	4.5 sec/100cc
Air Permeability (in-plane)	50.9 sec/100cc
PTFE Treatment	None
Microporous Layer (MPL)	None
Membrane Properties
Through-Plane Conductivity (mS/cm)	8.0 mOhm*cm²