De-protonation of Nickel Hydroxide by 200 kV Electron Irradiation

Previous studies of nickel hydroxide (Ni(OH)2) powders have shown that either heating or mechanical grinding can result in complete de-hydroxylation, leading to conversion to nickel oxide (NiO). In both cases, this process appears to occur in one stage, without evidence for any intermediate compounds being formed. During studies of Ni(OH)2 powders for applications in the positive electrodes of Ni metal hydride (NiMH) rechargeable batteries, using transmission electron microscopy (TEM), we have observed significant changes caused by exposure to the highly energetic electron beam used for imaging and analysis. It is shown here, using electron energy-loss spectroscopy (EELS), that de-hydroxylation under electron irradiation occurs in two stages, with nickel oxy-hydroxide (NiOOH) being formed at the intermediate stage.

Corrosion processes in battery systems based on non-aqueous electrolytes (a review)

The article presents some new results of the studies of corrosion processes in lithium battery systems with non-aqueous electrolytes. The following processes are considered: electrochemical corrosion of positive and negative electrodes, corrosion of structural materials, and electrochemical and chemical decomposition of non-aqueous electrolytes, which occurs simultaneously with the main electrochemical process. The main attention is paid to the role of corrosion processes on current collectors of current sources. Corrosion processes on aluminum current collector and stainless steel current collector for positive electrodes of lithium batteries are particularly considered. An important role of corrosion in the degradation of the lithium battery is emphasized. Case studies on corrosion in positive electrodes and lithium electrode are mentioned. Considerable attention is paid to the contact corrosion in aircraft, with an emphasis on the need for further studies of this process. The proposed corrosion mechanisms are considered.