Development of Zr-based hydrogen-absorbing alloys with laves phase for battery.

Fifteen Zr-based alloys with C15 type Laves phase for the negative electrode of Ni-MH battery were examined.Their compositions were designed by considering crystal structure, average atomic radius and average electronegativities of the alloys.The most part of them had a large discharge capacity over 380mAh/g and their electrochemical characteristics were excellent even for discharging in high-rate current density.The relationships between the hydride formation enthalpy(ΔH0)and the lattice volume and the average electronegativity of alloys were discussed on the basis of experimental results.