Another approach to the acceleration and the increase of yield of the hydrolysis reaction is in the use of salts, e.g., sodium, potassium, aluminium, or magnesium chlorides, either added into aqueous solution, or pre-mixed with magnesium hydride . It was assumed that dissolution of the salt during hydrolysis disintegrates the Mg(OH)2 passive layer thus promoting further interaction between MgH2 and water. The origin of this effect may be in the changes of ion exchange equilibria in the reaction solution which, in turn, may result in the changes of morphology of the Mg(OH)2 layer. As it was recently shown by Berezovets et al. , presence of MgCl2 in the solution results in the increase of size of Mg(OH)2 critical nuclei to form inhomogeneous layer on the surface of MgH2 particles thus facilitating diffusion of water molecules towards it. According to ref. , the maximum hydrogen evolution rate strongly depends on a way of halides introduction: the maximum rate of the hydrolysis of the mechanically treated mixtures of MgH2 with NaCl, MgCl2, NH4Cl and NH4Br was found to be higher than the one observed during the interaction of MgH2 with their solutions while the hydrogen yield does not depend on the way of introducing the salts. The acceleration of hydrolysis was also associated with the heat evolution when a salt is dissolved.