Abstract: The invention provides a cathode for an electrochemical cell, a cell incorporating the cathode, and a method of rendering the cathode resistant to a drop in capacity associated with cell cycling. The invention involves dispersing a transition metal, other than Ni, Fe, Cr, Co or Mn, in the active cathode substance, the cathode comprising an electronically conductive porous matrix impregnated with sodium aluminium halide molten salt electrolyte containing chloride ions. Said active cathode substance is an chlorinated nickel-containing substance dispersed in the matrix.