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Journal of Power Sources 78 1999 84–87
A lead–film electrode on an aluminium substrate to serve as a lead–acid
battery plate
L.A. Yolshina
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, V.Ya. Kudyakov, V.G. Zyryanov
Institute of High-Temperature Electrochemistry, Urals Branch of the Russian Academy of Sciences, KoÕaleÕskaya Str. 20, GSP 146, Ekaterinburg, Russian
Federation
Abstract
Compact lead layers have been deposited on the surfaces of aluminium and aluminium alloys. These coatings are uniform in thickness
and have high porosity. The lead–film electrode produced on aluminium plate can be used as the positive electrode in a lead–acid battery.
q 1999 Elsevier Science S.A. All rights reserved.
Keywords: Aluminium substrate; Lead–acid battery; Lead film; Battery plate
1. Introduction
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This study extends attempts 1 to improve the perfor-
mance of the lead–acid battery. The earlier work was
mainly devoted to investigations of lead–film electrodes
on copper and copper-coated titanium substrates. It was
found that lead-covered copper grids can be used as the
positive electrodes in lead–acid batteries and allow high
values of discharge current density to be obtained.
The aim of the present investigation is to study the
electrochemical characteristics and free corrosion rate of
aluminium-based, lead–film electrodes and to characterize
the solid products of interaction between the aluminium
and the lead-containing melt, as well as those of interac-
tion between the lead coating and sulfuric acid.
2. Deposition of lead coating
The deposition of continuous lead coatings on alu-
minium from aqueous solutions is practically impossible
because of the dense film of oxide which is always present
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on the aluminium surface 2 . Apparently, the formation of
lead–film electrodes on aluminium from a molten-salt
electrolyte is the only practical method. Since aluminium
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is virtually insoluble in liquid lead, even at 9008C 3 , the
resulting coating will consist of pure lead.
)
Corresponding author. Tel.rfax: q7-3432-488-153
Electron micrographs of a lead deposit on aluminium
are presented in Fig. 1, together with corresponding X-ray
phase analyses using Pb M
a
rays. Micrograph A1 shows
1
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that the lead layer has numerous pores diameter, 3–10
.
mm through the coating that reach the aluminium base. In
micrograph B1, the coating has a continuous uniform
thickness which features very fine porosity with pore
diameters of around 0.2 mm. This lead plate is shiny and
electrochemical investigations reveal that the discharge
current density does not exceed 70 mA cm
y2
. Thus, a
special study was conducted to form a lead coating with a
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developed surface of high surface roughness micrograph
.
C1 . The thickness of this film on the aluminium substrate
was determined by a direct metallographic method and by
lead etching in a concentrated solution of nitric acid. Both
methods found that the lead coating had a uniform thick-
ness of between 100 and 500 mm depending on the coating
conditions. The lead coating exhibits good adhesion with
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the aluminium surface Fig. 2 . According to X-ray phase
analysis, the thickness of the film is uniform and is
permeated by numerous fine pores of diameter 0.2 to 0.5
mm that do not reach the metal base. All further studies
were conducted on this leadraluminium electrode with a
rough surface and fine porosity.
3. Experimental
The lead layers were deposited on to smooth plates of
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aluminium 99.99% Al or aluminium alloy AD1 total
0378-7753r99r$ - see front matter q 1999 Elsevier Science S.A. All rights reserved.
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PII: S0 378-7753 99 00 016-6