摘要
利用交流阻抗法,对MHNi电池循环过程进行了跟踪研究,通过对交流阻抗谱的拟合解析,发现在循环过程中,电池多孔电极容抗效应CPE经历了先增大后减小的过程;欧姆阻抗在前150周期内变化不大,150周期以后显著增大。分析了这种现象产生的原因,认为电池充放电过程中正负极材料膨胀,挤压隔膜,逐渐使隔膜中的电解液减少,同时正负极材料的膨胀也导致了活性物质的粉化,造成其与导电基体间的接触电阻加大。
Properties of AA size Ni MH batteries was investigated in detail during charge/discharge by AC impedance technique. The results show that the CPE of porous electrode in the battery increases at first and decreases after 150 cycles. The ohmic resistance has little change in 150 cycles, but, it increases after 150 cycles. The reason of the phenomenon was analized. The author thinks that the positive and negative materials expanded during charge/discharge and pressed the separator. As a result, electrolyte in the separator was decreased. Moreover, the active materials was powdered due to the expansion of positive/negative materials and the contact resistance between it and conductive lose was increased. Expriement data were presented for improving the cycle life of Ni MH battery.
出处
《电源技术》
EI
CAS
CSCD
北大核心
2000年第1期25-27,共3页
Chinese Journal of Power Sources
基金
国家自然科学基金!资助项目 (597760 38)
关键词
NH-Ni电池
电化学
交流阻抗谱
充电
放电
Ni MH batteries
AC impedance
capacity impedance effect of porous electrode
ohmic resistance
