Hindawi Publishing Corporation
Volume 2013, Article ID 732815, 7 pages
Pulse-Current Electrodeposition for Loading Active Material on Nickel Electrodes for Rechargeable Batteries
M. D. Becker, G. N. Garaventta, and A. Visintin
Instituto de Investigaciones Fisicoqu´micas Te´ricas y Aplicadas (INIFTA), Facultad de Ciencias Exactas, UNLP, CCT La Plataı o
CONICET, Casilla de Correo 16, Sucursal 4, 1900 La Plata, Argentina Correspondence should be addressed to M. D. Becker; firstname.lastname@example.org Received 25 January 2013; Accepted 18 February 2013
Academic Editors: X. He, B. Lakard, D. Silvester-Dean, and W. Xing Copyright © 2013 M. D. Becker et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Although the pulse-current electrodeposition method is a commonly used technique, it has not been widely employed in electrode preparation. This method was applied to sintered nickel electrodes in a nickel salt solution containing additives. The active material that was obtained, nickel hydroxide, was studied using different characterization techniques. Electrodes impregnated with pulse current had higher capacity than those impregnated with continuous current. The active material is homogeneous and compact with optimum loading and good performance during discharge. These characteristics would provide a large amount of energy in a short time due to an increase in the electrode kinetic reaction.
Nickel hydroxide has many applications in the positive electrodes of alkaline cells such as nickel cadmium (Ni-Cd), nickel hydrogen (Ni-H2 ), nickel metal hydride (Ni-MH), and
nickel iron (Ni-Fe) cells [1–3].
The chemical pasting of a mixture of active material
on a support conductor is used to prepare the positive
electrodes of alkaline batteries . This kind of electrode is used in the batteries of mobile phones, mp3s, emergency
lights, and electric vehicles. Nickel hydroxide should have
a homogeneous particle size and bulk distribution. Two
methods are commonly used to obtain this kind of nickel
hydroxide: indirect chemical precipitation and direct chemical precipitation. In both cases nickel hydroxide is obtained as a powder that then must be properly prepared to build
the electrodes. For the manufacture of nickel hydroxide
electrodes for use in high-performance batteries, such as
nickel hydrogen batteries used as power source in space
satellites, the impregnation technique used consists of the
cathodic electrodeposition of sintered nickel plates. There are several variations of this technique such as (i) the Kandler process , which includes an electrochemical precipitation stage, working with a 0.3 M Ni (NO3 )2 solution and an initial pH between 3 and 4, which is adjusted with nitric acid, and
(ii) the process developed by Pickett and Maloy , which
applies the same principle, but using a nickel nitrate solution in alcohol, pH = 3.5. These are the impregnation processes
that were taken as the basis to develop our technique for the preparation of nickel hydroxide electrodes for high discharge capacity and long service life. The different properties of the electrodes that make them superior are not yet well known in the literature [7–9].
When the electrode is charged, nickel hydroxide is oxidized to nickel oxyhydroxide. During discharge the reaction is reversed, and Ni(OH)2 has good cyclability and high energy density, both of which are important characteristics for alkaline batteries. To increase the energy density in each of these batteries, it is necessary to improve the performance of the positive electrode [10, 11]. The electrochemical energy storage in nickel hydroxide electrodes is related to the reversible characteristics of the redox...
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