AA型密封MH-Ni电池内阻特性研究

研究了ＡＡ型密封ＭＨ－Ｎｉ电池在充放电过程及循环寿命测试实验中的内阻及内压变化情况。实验结果表明，在充放电过程中，内阻变化受正负极活性物质氧化态／还原态的转化反应影响，充电过程还与内压有关；在循环寿命测试实验中，由于正极膨胀及电解液的减少，内阻增大，导致电池容量衰减，性能降低。因此，减小正极膨胀和保持电解液量是降低内阻、提高电池性能、延长电池循环寿命的有效方法。

Research on the internal resistance of AA size sealed Ni-MH batteries

The variation of the internal resistance and inner pressure of AA size sealed Ni MH batteries were investigated in the charge/discharge and cycle life test. The results show that the transformation of O/R of active materials cause the internal resistance change during charge/discharge. Moreover, the inner pressure also affectes the internal resistance during charge. In cycle life test, the internal resistance increased because the nickel electrode expanded and the electrolyte decreased. As a result, the capacity of battery become lower and its performance was decreased. So preventing the nickel electrode from expan ding and maintaining the electrolyte should be effective methods to avoid the internal resistance increasing thus the performance and cycle life of battery can be improved.