Fundamental and applied works involving the electrochemical utilization of metal hydrides are reviewed. In the first part of the paper, studies that investigated metal hydrides for hydrogen storage in nickel hydrogen batteries are reviewed. These studies showed that use of hydrides lowered the operating pressures in nickel hydrogen cells, which could lead to improved energy density. However, results regarding degradation of the hydriding material in an aqueous medium were conflicting. In the second part of the paper, the use of metal hydrides as reversible hydrogen electrodes is discussed. Studies reviewed included thermodynamic and kinetic investigations of a variety of hydriding materials. Conflicting results among studies are reconciled where possible, and conclusions are drawn regarding the feasibility of electrochemical utilization of metal hydrides, with suggestions for further work.

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The characteristics and effects of the lithium passivation layer in the lithium sulfur dioxide false(normalLi/SO2false) cell have been studied. Four aspects have been investigated: (i) passivation layer‐induced polarization; (ii) effects of long‐term, low discharge rates; (iii) chemistry of the lithium passivation layer; and (iv) kinetics of the passivation layer growth. Polarization studies showed that an initial polarization (voltage delay) was in some cases followed by a secondary polarization. Studies of the effects of long‐term, low discharge rates indicated that low discharge rates modified the lithium passivation layer, which resulted in increased lithium corrosion and decreased cell capacity. The degradation was greater at higher temperature. Results of studies of the chemistry and formation kinetics of the lithium passivation layer were interpreted in terms of a primary layer, which was responsible for the passivation, and a thicker, porous secondary layer. Formation of the secondary layer is exacerbated by partial discharge. The secondary layer results from precipitation of the Li corrosion products, and was found to contain Li2S2O4 , Li2S2O5 , and Li2SnormalnO6 , where normaln>2 . The primary layer is responsible for the initial polarization (voltage delay) under load, whereas the secondary layer induces a second polarization that inhibits high‐rate discharge.

Structural properties of alkaline electrolyte films on battery electrode and separator materials are investigated. Thermodynamic principles that affect film formation are presented, and a model is developed that predicts the wetting‐dewetting transition, for a network of fibers, as a function of electrolyte volume and fiber network compactness. Film characteristics on single fibers and networks of fibers of a variety of materials are studied by a laser diffraction technique and by conductivity measurements. Materials studied include nickel, cadmium, nylon, polypropylene, and Teflon. Wetting characteristics of actual separator materials are studied in a simulated battery environment. Experimental results yield good agreement with the model.