Ti–Ni alloys as MH electrodes in Ni–MH accumulators

In hydrogen solid–gas reaction at 300 K and 1 bar, the hydrogen content for Ti3.87Ni1.73Fe0.7Ox (0.2≤ × ≤0.8) alloys was in range 1.93–0.05 (Cwt.H,%), and discharge capacity of 360–235 A h/kg was achieved accordingly. The Δ H H 2 and Δ S H 2 values of −32.29 kJ mol−1 and −111.04 J mol−1 K−1, respectively, for Ti3.87Ni1.73Fe0.7O0.5 alloy were obtained using experimental PCT relations, where hysteresis effect was only slightly visible. The half-cell potentials (vs. Hg/HgO) of metal hydride (MH) electrodes based on Ti3.87Ni1.73Fe0.7Ox (0.2≤ ×≤ 0.8) alloys were calculated. Ni1.73Fe0.7Ox (0.2≤ × ≤0.5) alloys might meet the requirements of general criteria for MH electrode, but only with the exception of good corrosion resistance.