UDC 544.6 DETERMINATION OF SURFACE CAPACITY QS AND SUPERFICIAL ACTIVE LAYER THICKNESS dS OF LaNi5 Le Xuan Que1 1 , Do Tra Huong2 BASED INGOT ELECTRODES , Nguyen Anh Tien3 , Uong Van Vy1 Institute of Tropical Technology, Institute of Science and Technology, 18 Hoang Quoc Viet road, Hanoi, Vietnam 2Thai Nguyen City University of Pedagogy, Thai Nguyen City, Vietnam 3 Ho Chi Minh City University of Pedagogy, Ho Chi Minh City, Vietnam Received to editors 21.10.2010 ingot electrodes was carried out with an extrapolation to infi nite scan rate, taking into account the polarisation direction as charging or discharging. <...> The thickness of superfi cial active layer dS values. <...> Based on the variation of QS suitable Co ratios corresponding to two opposite processes: charging and discharging. <...> Keywords: LaNi5 and dS materials, surface capacity, active layer thickness, Co content. <...> However, in almost all electrochemical kinetic and mechanistic investigations of the LaNi5 Nickel-metal hydride (Ni/MH) batteries are the most suitable electric source for mobile devices, such as electronic instruments, hand-held computers, mobile phones, especially they are the most promising source of electric power for green vehicles. <...> The effective surface of the electrode is roughly hundreds of cm2 , and the current hence is very high, that is not usually suitable for kinetic and mechanistic studies, exclusive © Le Xuan Que, Do Tra Huong, Nguyen Anh Tien, Uong Van Vy, 2010 of the additives secondary effects. <...> One of the most signifi cant advantages of ingot electrodes is the possibility to dearly defi ne the surface, as its geometry and morphology, and consequently InE is practically suitable to study surface electrochemical phenomena. <...> Meanwhile, in general, the electrode material surface properties have a deciding role for the kinetics of electrochemical processes. <...> That is in particular signifi cant for electrodes materials research in NiMH batteries. <...> However, there are only some papers mentioning the application of ingot electrodes for materials research in Ni-MH batteries [14, 15]. <...> Composition and crystalline structural analyses of the powdered materials were <...>