Affiliation:
1. Czestochowa University of Technology , Faculty of Production Engineering and Materials Technology, Czestochowa , Poland
2. Institute of Low Temperatures and Structure Research PAS , Wrocław , Poland
Abstract
Abstract
The hydrogenation and corrosion behaviour of La2Ni9 · CoSn0.2 alloy was analysed in respect of its use in Ni–MH batteries. It has been proved that the presence of tin in the alloy causes a decrease in hydrogen equilibrium pressure. In the electrochemical studies several techniques, such as chronopotentiometry, multi-potential steps, linear sweep voltammetry and the potentiokinetic polarization were applied to characterize the electrochemical properties of a La2Ni9CoSn0.2 powder composite electrode. During long cycling, powder particles undergo micro-cracking or other forms of surface development causing a progressive increase in the exchange current density of the H2O/H2 system, but, on the other hand, this increase favours corrosion processes such as the electrode material's oxidation. This is also reflected in the capacity loss values.
Subject
Materials Chemistry,Metals and Alloys,Physical and Theoretical Chemistry,Condensed Matter Physics