Electrochemical properties of titanium-based hydrogen storage alloy prepared by solid phase sintering

The structure and electrochemical properties of titanium-based hydrogen storage alloy prepared by solid phase sintering at 1123 K were investigated. The result of X-ray diffraction (XRD) showed that the sintered alloy mainly consists of Ti₂Ni phase coexisting with TiNi, TiNi₃ and Ni phases. The alloy had a maximum discharge capacity of 205 mAh/g at a discharge current density of 60 mA/g and showed a discharge capacity of 146 mAh/g at 150 mA/g. The results of linear polarization (LP) and potential-step measurement presented that the exchange current density and hydrogen diffusion efficient of the alloy were 100 mA/g and 4.2 × 10^-9 cm²/s, respectively. The electrochemical performance of the alloy could be effectively improved by using solid phase sintering.