Effect of LiH on electrochemical hydrogen storage properties of Ti55V10Ni35 quasicrystal

• At the process of charge/discharge, the reversible reaction LiH ↔ Li+ + H− can take place in LiH.
• Lithium-ions may get into the interspaces in the quasicrystal, which attracts more hydrogen ions.
• The results of HRD indicate that the LiH plays an important role in improving kinetic properties.

The electrochemical hydrogen storage properties and mechanisms of the Ti55V10Ni35 quasicrystal + xLiH(x = 3, 6 and 9 wt.%) system are investigated and discussed in this paper. A composite material in the Ti55V10Ni35 quasicrystal and system has been synthesized moderately by means of mechanical milling under an argon atmosphere, which can avoid reaction of releasing of hydrogen during the process of milling. The results indicate that the addition of LiH significantly improves the electrochemical characteristics of composite material. The maximum discharge capacity increases from 220.1 mAh/g to 292.3 mAh/g on Ti55V10Ni35 + 6 wt.% LiH, and the cycling stability is also enhanced too. In addition, the high rate dischargeability (HRD) is ameliorated remarkably, and the value of HRD value at 240 mA/g rises by 78.1%–87.8% for Ti55V10Ni35 + 6 wt.% LiH alloy electrodes. The improvement of characteristics of the electrochemical hydrogen storage characteristics may be attributed to LiH, which has excellent electrochemical activity.

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