Electrochemical properties of Ml(NiCoMnCu)5 used as an alkaline fuel cell anode

The electrochemical properties of AB(5)-type rare earth-nickel multicomponent compounds Ml(NiCoMnCu)(5) (Ml: La-rich mischmetal) used as an alkaline fuel cell anode were investigated at 30 degrees C. A double-layer porous film structure with foamed nickel as current collector was adopted for the anode. A catalyst layer made of Ml(NiCoMnCu)(5) alloy powder and a 60% aqueous suspension of polytetrafluoroethylene (PTFE) was on the electrolyte side, and a waterproof layer made of a Teflon aqueous suspension and Na2SO4 powder was on the gas side. The experimental results revealed that the anode performance strongly depends on the PTFE content of the catalyst layer, the thickness of the catalyst layer and the waterproof layer, and the cold compression pressure for electrode formation. When these four parameters were 12 wt.%, 0.25 mm, 0.2 mm and 12 MPa, respectively, the anode had a life-time of approximatly 550 h at a current density of 20 mA/cm(2). (C) 1999 Elsevier Science S.A. All nights reserved.