提高MH-Ni电池循环寿命的研究

Research on the cycle life of Ni-MH battery

循环寿命是MH Ni电池的重要指标之一。从材料的角度综述了MH Ni电池循环寿命下降的原因 ,指出负极贮氢合金性能的衰减、正极氢氧化镍性能的恶化和隔膜本身性质的变化所带来的碱液丧失是导致MH Ni电池循环寿命降低的主要因素。同时 ,指出优化负极合金的组分 ,对合金进行表面处理可提高合金的抗粉化、氧化或耐酸碱腐蚀的能力 ;通过添加合适的添加剂如Co、Zn、Cd等可提高氢氧化镍的活性 ,抑制镍电极的膨胀并提高镍电极的充电接受能力 ;选用面电阻小、吸碱率大、综合性能好的隔膜可保证电池内合适的电解液量 。

The cycle life was one of the most important parameters of Ni-MH battery. The reason for the decay of cycle life of Ni-MH battery was reviewed from the point of view of the material. The decay is mainly caused by the performance deterioration of hydrogen storage alloy in anode and of Ni(OH) 2 in cathode as well as the degradation of the separator resulting in the alkaline loss in Ni-MH battery. Some methods adopted to improve the cycle life of Ni-MH battery were also indicated, including optimizing the anode alloy composition and applying surface treatment method, to improve the capability of antioxidation, antipulverization and resistance to electrolyte of anode alloy. Selecting proper cathode additives, such as Co, Zn, Cd, etc., can increase the activities of Ni(OH) 2 electrode and reduce its swell as well as improve its chargeable capability. In addition, the separator with smaller surface resistance, better ability of absorbing the electrolyte can prevent from the loss of the electrolyte during the cycle of Ni-MH battery, therefore, the battery have better cycle life.