Electrochemical Properties of the Amorphous Ti3Ni2 Alloy in Ni/MH Batteries

摘要:

采用机械球磨晶态Ti3Ni2 (Ti2Ni/TiNi)合金的方法制备非晶态的Ti3Ni2合金，并研究其电化学性能。充放电测试结果显示，非晶态Ti3Ni2合金成功地解决了晶态Ti3Ni2合金在高温下（333 K）循环寿命极短的缺点。在333 K循环19次后，相对于晶态Ti3Ni2合金较低的容量保持率(39.47%)，其非晶态合金有效的将容量保持率提高到88.83%。通过Tafel极化，线性极化以及交流阻抗测试，发现这种改善源于非晶态Ti3Ni2合金的耐蚀性远优于其晶态合金。

Abstract:

Amorphous Ti3Ni2 (Ti2Ni/TiNi) alloy has been prepared by mechanical milling of crystalline Ti3Ni2 alloy, and its electrochemical properties were investigated. The results of charge and discharge test show that the amorphous Ti3Ni2 alloy can resolve the problem of extremely short cycle life of crystalline Ti3Ni2 alloy at high temperature (333 K). The capacity retention rate of amorphous Ti3Ni2 alloy is greatly increased to 88.83% at 333 K compared with the retention rate of its crystalline counterpart 39.47% after 19 cycles. Based on analysis of Tafel polarization, linear polarization, and electrochemical impedance spectroscopy, it is found that the major reason for the improvement is the presence of amorphous Ti3Ni2 alloy, which has much better corrosion resistance compared with its crystalline counterpart.