Ti-ni Alloys As Mh Electrodes In Ni-mh Accumulators

摘要

In hydrogen solid-gas reaction at 300 K and 1 bar, the hydrogen content for Ti_(3.87)Ni_(1.73)Fe_(0.7)O_x (0.2 ≤ x ≤ 0.8) alloys was in range 1.93-0.05 (Cwt.H,%), and discharge capacity of 360-235 Ah/ kg was achieved accordingly. The △H_(H_2) and △S_(H_2) values of -32.29 kJ mol~(-1) and -111.04 J mol~(-1)K~(-1), respectively, for Ti_(3.87)Ni_(1.73)Fe_(0.7)O_(0.5) 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 Ti_(3.87)Ni_(1.73)Fe_(0.7)O_(0.5) (0.2 ≤ x ≤ 0.8) alloys were calculated. Ti_(3.87)Ni_(1.73)Fe_(0.7)O_(0.5) (0.2 ≤ x ≤ 0.5) alloys might meet the requirements of general criteria for MH electrode, but only with the exception of good corrosion resistance.