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对La Ni3.8Co0.6Mn0.3M0.3(M=Ni,Al,Cu)储氢合金在238,273,303和323 K温度下的结构和电化学性能进行了一系列的实验研究。A,B,C分别代表La Ni4.1Co0.6Mn0.3(Ni替代),La Ni3.8Co0.6Mn0.3Al0.3(Al替代)和La Ni3.8Co0.6Mn0.3Cu0.3(Cu替代)3种储氢合金,通过X射线衍射仪分别对样品A,B,C的结构进行了研究,对样品A,B,C合金粉末制成的电极进行了模拟电池测试。结果证实,制备的合金均由具有Ca Cu5型六方晶格结构的La Ni5相构成。3种合金中,Cu替代的合金电极低温性能得到改善,Al替代的合金电极高温放电能力得到提高。交流阻抗图谱分析表明,B合金电极样品的高温放电能力提高是由于合金电极表面形成的致密氧化膜层减缓了合金腐蚀所致,样品B,C的高倍率性能衰退是由于电极表面的充放转移反应和氢原子扩散速率下降造成的,而样品C的优良低温性能则是合金电极表面高的充放电转移反应速率所致。
A series of experimental studies on the structure and electrochemical properties of La Ni3.8Co0.6Mn0.3M0.3 (M = Ni, Al, Cu) hydrogen storage alloy at 238, 273, 303 and 323 K were carried out. A, B and C represent La Ni4.1Co0.6Mn0.3 (Ni substitution), La Ni3.8Co0.6Mn0.3Al0.3 (Al substitution) and La Ni3.8Co0.6Mn0.3Cu0.3 (Cu substitution) 3, respectively A hydrogen storage alloy was prepared. The structures of samples A, B and C were studied by X-ray diffractometer. The simulated batteries were tested on the electrodes made of the samples A, B and C alloy powders. As a result, it was confirmed that the prepared alloys each consisted of a LaNi5 phase having a CaCu5-type hexagonal lattice structure. Among the three alloys, the low-temperature performance of Cu-substituted alloy electrodes is improved, and the high-temperature discharge capability of Al-substituted alloy electrodes is improved. AC impedance spectroscopy analysis showed that the high-temperature discharge capacity of B alloy electrode samples was enhanced due to the corrosion of the alloy due to the dense oxide film formed on the surface of the alloy electrode. The high-rate performance degradation of samples B and C was due to the charge- Reaction and hydrogen atom diffusion rate caused by the decline, while the excellent low-temperature performance of the sample C is the alloy electrode surface charge-discharge transfer reaction rate due to high.