IMPROVEMENTS IN SECONDARY PILES OR BATTERIES OR ACCUMULATORS OF ELECTRICITY
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by Edward Griffith Brewer at the Office
of the Commissioners of Patents on the 6th March 1883. Communicated to
him from abroad by Emile Pfeifer of Antwerp Belgium
EDWARD GRIFFITH BREWER of 33 Chancery Lane in the County of Middlesex
"IMPROVEMENTS IN SECONDARY PILES OR BATTERIES OR ACCUMULATORS OF
ELECTRICITY." (A communication to me from abroad by Emile Pfeifer of Antwerp
Belgium)
According to this invention this new pile is obtained by the employment of
spongy lead obtained electrolytically or by chemical precipitation.
To obtain spongy lead according to this Invention by electrolytic means a lead
salt preferably sugar of lead is decomposed by an electric current. The operation
is conducted as now used in galvanoplasty or electro metallurgy. In a concentrated
solution of sugar of lead two plates of lead of large surface are introduced one
being in communication with the positive, the other with the negative pole of an
electric source. The sugar of lead is decomposed, the metal is precipitated on the
negative plate in form of leafy crystals composing a spongy mass while the oxygen
of the base and the acid are deposited on the positive pole whose plate keeps the
solution in a constant degree of saturation.
To obtain spongy lead according to this invention by chemical precipitation
it is sufficient to treat a concentrated solution of a lead salt preferably sugar of
lead by a metal preferably zinc, which displaces the lead out of its combination
and precipitates it in the form of a spongy mass.
According to the circumstances under which the accumulator is to be used or
operate so the spongy lead constituting the active matter must be arranged.
The spongy lead is used in layers on the two surfaces of the rectangular lead
plates even or perforated and provided on one side with a prolongation intended
to act as an electrode. The spongy lead is maintained upon the plates by means
of a felt, of any other suitable fabric or parchment paper and the plates thus
prepared are placed in a vase containing acidulated water in the same way as the
plates of the accumulator with parallel so called Planté plates.
To maintain the spongy lead, rectangular frames of lead, wood or any other
matter are used provided at one corner with a prolongation as an electrode. The
thickness of the frames varies with the intended capacity of accumulation. Inside

page_text: of the frames and in the same direction as their sides lead wire or lead strips are
applied. The inner space of the frames is filled up with spongy lead more or less
compressed. The wire or strips are thus placed in the middle of the active mass.
The pile is completed by arranging the frames in the same way as the plates of the
so called Planté accumulator with parallel plates.
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The more or less compressed spongy lead is arranged in form of rectangular
layers maintained by means of felt or any other suitable fabric. The layers are
crossed lengthwise by lead wires or strips coupled together at one extremity to
form electrodes. Two layers are rolled one in the other in spiral form and placed
in a vase containing acidulated water just as the lead sheets of the ordinary so
called Planté accumulator.
The advantages of this system of accumulator are as follows.
1 The long and expensive operation of the formation or electro chemical
preparation of the pile, indispensable in all the other kinds of accumulators, is
entirely done away with because its molecular constitution enables the spongy
lead to absorb directly without the formation of any gas proceeding from the
action of the primary current.
2nd The spongy lead precipitates being of a very uniform molecular and physical
constitution, the internal resistance of the pile is diminished, while at the same
time the cause of loss proceeding from an incomplete formation is done away with.
For the same reason the constancy of the current reaches its maximum.
3rd The weight being equal, the capacity of accumulation is, greater than that of
other accumulators the electrolytic action of the primary current penetrating the
whole mass of the spongy lead.