It was noted that the crystal structure of nickel hydroxide consisted of a repeated

stacking of charge-neutral layers, AbC AbC AbC, where A and C were hydroxyl

ions which were hexagonally close-packed, while b was a divalent nickel ion

occupying an octahedral interstitial site. The random incorporation of other layers,

such as AcB, BaC, CbA, etc., within the AbC AbC AbC… stacking sequence could

lead to the formation of stacking faults. Simulations showed that each kind of

stacking fault produced a characteristic pattern of non-uniform broadening of the

peaks corresponding to the (h0ℓ) reflections in the powder X-ray diffraction pattern

of nickel hydroxide. The electrochemical properties of each type of faulted nickel

hydroxide was investigated. It was found that a 2H2-type faulted nickel hydroxide

exhibited a better electrochemical activity as compared with 3R2-type faulted

nickel hydroxide.

The Effect of Stacking Faults on the Electrochemical Performance of Nickel

Hydroxide Electrodes. T.N.Ramesh, P.V.Kamath: Materials Research Bulletin,

2008, 43[11], 2827-32