Effects of self-stress on the hydrogen absorption into palladium hydride electrodes of plate form under galvanostatic conditions

Effects of diffusion induced stress on the hydrogen absorption into plate form electrodes of b-phase PdHx are discussed numerically based on the Volmer–Tafel route of the hydrogen evolution reaction, and thermodynamic considerations involving stress fields and non-ideal interactions of hydrogen in the electrode. It is found that the self-induced stresses enhance the absorption rate and may exceed the yield stress, especially when the thickness of the plate and/or charging current (or negative potential) increase. On the other hand, a plate with both sides exposed to electrolyte absorbs hydrogen more rapidly than that with only one side exposed to electrolyte under the same equivalent thickness and other conditions. Of course, the stresses developed in the former plate are always greater than those of the latter. © 1999 Elsevier Science S.A. All rights reserved.