PRODUCING ELECTRODE ACTIVE LAYER FROM ACTIVE CARBON PARTICLES AND FIBRILLATED POLYTETRAFLUOROETHYLENE COATED CARBON BLACK

摘要

This invention covers fibrillated matrix active layers for gas-fed electrodes having improved strength, service durability and resistance to mechanical failure as well as methods of making such active layers and electrodes. The term "matrix" is used to indicate that the active carbon particles (which constitute the main component thereof) are disposed within an unsintered network of carbon black/PTFE (fibrillated) material. The finished electrodes are generally three-layer laminates wherein said active layer is positioned between a hydrophobic (wet-proofing) backing layer on its nonworking surface and a current distributor on its working surface. Key features of technical advancement in this invention include the use of active carbons as the main electrocatalytic component of the active layers disposed within a strong, highly conductive matrix, the use of a shear blending step to mix the ingredients and fibrillate said matrix and the final formation of the complete mixture into an active layer without sintering.