Layered carbon electrode for electrochemical cells

摘要

There is provided an electrode structure comprising a current collector sheet and first and second layers of electrode material. Together, the layers improve catalyst utilization and water management. The first electrode layer is between the current collector sheet and the second electrode layer. The first layer comprises a first group of carbon particles and the second layer comprises a second group of carbon particles. The first layer is uncatalyzed or catalyzed with a first group of very finely divided catalytic particles; and the second layer is catalyzed with a second group of very finely divided catalytic particles. The weight ratio of catalytic particles to carbon particles of the first layer is less than that of the second layer. In one embodiment, each one of the carbon particle groups comprises a plurality of the carbon particles having internal and external surfaces defining a plethora of pores within and between the carbon particles. The very finely divided catalytic particles are supported on the internal and the external surfaces of the carbon particles. In another embodiment, the first layer is uncatalyzed and the second layer comprises the carbon particles having very finely divided catalytic particles supported on the internal and the external surfaces of the carbon particles.