金属钴对储氢合金电极的表面修饰研究

运用真空蒸镀法时MH／Ni电池储氢合金电极进行了镀覆金属钴的表面修饰，测试了电池的放电容量、高倍率放电性能、循环寿命和充电时的内压，利用XPS和XRD时电极进行了表面和结构分析。实验结果表明，运用该方法对电极进行表面修饰可以降低电池内阻，提高电池的放电容量和放电电压，极片经过修饰的电池，5C（8．5A）放电容量提高了120mAh，放电平台电压提高了约0．05V，内阻降低了19．3％。极片经过表面镀钴后，显著改善了电池的循环性能，电池500周循环后的放电容量仍为初始容量的94．09／6，同时，电池在充电时的内压有了明显的降低，充电效率有了较大的提高。

Study on the surface modification of the MH electrode with cobalt

The metal-hydride electrode of the MH/Ni batteries was modified with a thin cobalt film using vacuum evaporate plating technology.The discharge capacity,high-rate dischargeability,cyclic stability and inner pressure of the batteries were tested.The XPS and XRD were used to analyze the surface and structure of the electrode.Experimental results indicated that the surface modification could decrease the resistance and increase the discharge capacity and voltage of the batteries.After surface modification,the discharge capacity at 5C(8.5A) was increased by 120mAh and discharge voltage was increased by 0.05V,the resistance of the batteries was also decreased by 19.3%.The cyclic stability of the batteries was remarkably improved after surface modification. The remaining capacity of the modified batteries was 94.0% of the initial capacity even after 500 cycles.The inner pressure of the batteries during overcharging was lowered and the charging efficiency of the batteries was enhanced.