Electrochemical cell

Claim 1

An electrochemical cell comprising a negative electrode, the electrochemically active material of which consists of an intermetallic compound forming hydride with hydrogen, which compound has the CaCu 5 -structure and the compositional formula AB m C n , where m+n is between 4.8 and 5.4, where n is between 0.05 and 0.6, in which A consists of Mischmetall or of one or more elements selected from the group consisting of Y, Ti, Hf, Zr, Ca, Th, La and the remaining rare earth metals, in which the total atomic quantities of the elements Y, Ti, Hf and Zr may not be more than 40% of A, in which B consists of two or more elements selected from the group formed by Ni, Co, Cu, Fe and Mn, where the maximum atomic quantity per gram atom of A is for Ni: 3.5, for Co: 3.5, for Cu: 3.5, for Fe: 2.0 and for Mn: 1.0, and in which C consists of one or more elements selected from the group formed by Al, Cr and Si in the indicated atomic quantities: Al: 0.05-0.6, Cr: 0.05-0.5 and Si: 0.05-0.5, characterized in that the electrochemically active material additionally comprises a quantity Ni which quantity of Ni, is present as a separate, finely-dispersed phase, the maximum atomic quantity of Ni per gram atom of A is 3.5, and the total of m+n and the said atomic quantity of Ni per gram atom of A lies between 5.0 and 5.5.