Russian Journal of Applied Chemistry, 2013, Vol. 86, No. 10, pp. 1483−1492.
Pleiades Publishing, Ltd., 2013.
Original Russian Text © A.I. Andrukhiv, A.A. Bachaev, I.V. Skobeleva, 2013, published in Zhurnal Prikladnoi Khimii, 2013, Vol. 86, No. 10, pp. 1525−1534.
AND INDUSTRIAL INORGANIC CHEMISTRY
Optimization of the Composition of Zincate Electrolyte
for Fabrication of Electrodeposited Zinc Powder
A. I. Andrukhiv, A. A. Bachaev, and I. V. Skobeleva
Alekseev State Technical University of Nizhni Novgorod, Nizhni Novgorod, Russia
Received July 30, 2013
Abstract—Effect of Tsinkamin-02 additive on characteristics of electrolytically fabricated zinc electrode for
backup power sources was studied. Its inﬂ uence on how a zinc powder is formed, deposition process parameters
(current efﬁ ciency by zinc, cathodic polarization), and utilization factor of the active substance of the negative
electrode in a nickel–zinc power source discharged in a high-intensity mode was determined. The component
concentrations of the electrolyte used to deposit the zinc powder were optimized. An explanation was suggested
for the mechanism of Tsinkamin-02 action.
Dry-charged porous zinc electrodes are used in
silver–zinc (SZB) and nickel–zinc (NZB) batteries
and air–zinc power cells (AZPC) . The porous zinc
electrode has stable characteristics in the dry-charged
state and provides a high output capacity in high-
intensity discharge modes.
The most rational way to fabricate porous zinc
electrodes for power cells of the dry-charged type is by
electrolytic deposition of spongy dispersed deposits from
zincate electrolytes . By changing the electrolysis
conditions (cathodic current density, zincate and alkali
concentrations, temperature) and introducing additives,
it is possible to affect the structure of the spongy deposits
and, consequently, the electrode properties. It has been
shown  that electrodes made of an electrolytic zinc
sponge exhibit high electrical characteristics when
operating in power sources.
Zinc is originally deposited from additive-free
zincate solutions as a compact deposit, and only after
a certain time (the so-called induction period) zinc
projections appear on the cathode surface . A similar
behavior is observed in deposition of copper . In this
case, microdeposit particles can serve as active centers
of 3D nucleation at higher cathodic overvoltages.
Raising the zinc deposition current density makes the
induction period shorter . In deposition of powders,
the deposition of zinc is not complicated in the initial
period by a diffusion hindrance, i.e., the conditions
are close to those in which electroplated coatings are
formed. During further powder growth, a spongy zinc
deposit is formed, which leads to an increase in the
reaction surface area and the corresponding decrease in
the true current density, as indicated by the decay of the
polarization of the cathodic process .
Upon introduction of additives, such as some
surfactants used in electroplating as brighteners, the
current efﬁ ciency and structure of deposits differ from
those produced from additive-free zincate solutions. As
a rule, the additives make lower the limiting diffusion
current of reduction of zincate ions and enhance the
electrode polarization . For example, a zinc utilization
factor of 78% in high-intensity discharge modes has
been obtained upon introduction of a methacrylic acid
(MAA) additive into the electrolyte for deposition of
powder zinc electrodes . The electrodes possessed
a high mechanical strength. However, this effect was
only observed in sponge deposition at very high current
densities (199 A dm
), which leads to an additional
energy expenditure and low current efﬁ ciency by zinc.