CNT-GoO Complex Conductive Agent for the Positive Electrodes of MH/Ni Batteries

摘要

CoO was usually added to the positive electrodes of MH/Ni batteries as the conductive ageat. In this paper, well crystallized multi-walled carbon nanotubes (CNTs) with diameter about 10 ran were added to the positive electrodes of MH/Ni batteries together with CoO. During the process of transformation from CoO to CoOOH, a complex conductive network was created with CNTs as the frame, Because of the high conductivity and the excellent tension characteristics of CNTs, the charge-transfer capability of the electrode was improved and the integrality of the complex conductive network was enhanced. The electrochemical measurements indicated that the impedance of the electrode with CNT-CoO complex conductive agent was lessened compared to the electrode with simple CoO agent. Performance tests of the sealed batteries showed that the positive electrodes with CNT-CoO complex conductive agent exhibited higher discharge voltage, improved capacity, modified discharge stability and prolonged lifespan, especially at high current rates.