Improvements in Secondary Batteries.
Year: 1899

page_text: _Date of Application, 10th Apr., 1899-Accepted, 24th Mar., 1900
Improvements in Secondary Batteries.
A communication from abroad by THE PREISS ELECTRIC STORAGE SYNDICATE
LIMITED, a Company registered under the Provisions of The Companies
Act, 1892 (South Australia), and having its registered Office at Cowra
Chambers, Grenfell Street, Adelaide.
I, PHILIP MIDDLETON JUSTICE, of 55 and 56, Chancery Lane, London, W.C.,
Chartered Patent Agent, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to improvements in secondary batteries, and refers
more particularly to a special form of secondary battery in which the stored
current of lead or other plates which have been already charged with electricity
in a secondary or other battery in the ordinary way, is discharged.
In the secondary or storage batteries at present in use, positive and negative
plates are arranged in series in a solution of sulphuric acid or other suitable
Huid electrolyte. Such batteries are however, too heavy and cumbersome for
use in traction and for other like purposes when the battery itself requires to be
transported. In addition to this, the fluid acid electrolyte is through spilling
often a source of danger and inconvenience, and the acid electrolyte, if strong,
is liable to cause the formation of creeping salts, thereby decreasing the effective-
ness of the battery.
The object of the invention is to provide a secondary battery of such greatly
reduced weight and size as to be convenient for purposes in which the battery
itself requires to be transported during discharge, and in which through there
being no more fluid electrolyte than the blanketing can absorb, the disadvantages
of spilling and creeping salts are avoided.
In the charging of the plates for use in this improved secondary battery, an
electrolyte consisting of an acid in a very dilute form can be utilised, thereby
also preventing the formation of creeping salts in the charging battery.
The improved secondary battery is, from its construction, specially suitable
for use in traction and other purposes, in which lightness is essential and the
batteries themselves require to be constantly handled or transported.
The invention consists in the construction of a battery in which one or more
positive plates are covered with woollen or other absorbent material, and if of
the grid pattern, the interstices of the plate are filled with woollen material
prior to being charged. The positive plate preferably of lead, is then charged
in the ordinary way. The positive lead plates are as stated covered with woollen
blanketing or other suitable absorbent material. This need only be of the thick-
ness of one coating of blanketing, and will be sufficiently moistened by the
electrolyte employed in the charging battery. The plate when charged is removed
therefrom and allowed to drain before being placed within the negative casing.
The charged plates may after draining be transported from place to place, or he
stored away for subsequent use as required. The small amount of electrolyte

page_text: then remaining not only, considerably reduces the weight of the battery to be
transported, but also insures an absence of creeping salts. As stated, should
the positive plates employed be of the ordinary grid or perforated pattern, the
interstices are filled with woollen or other absorbent packing, which also becomes
saturated with the fluid, electrolyte.
In order to contain the charged positive plate or plates, a closely fitting casing
of zinc or other suitable metal is employed. This casing acts merely as the
negative pole or conductor, and is provided with a suitable terminal in the
ordinary way. By this means the negative casing or plate can be brought into
close contact with the covering of the positive plate, and for this purpose the
The
outer casing is made to closely fit round the same as above mentioned.
internal resistance of the cell is thereby greatly reduced, and the flow of the
current correspondingly increased.
It has been found in practice also that the employment of a zinc casing as a
negative pole causes under the action of the weak acid of the electrolyte a
slight primary action to be generated, and that this, slight primary current
considerably assists the flow of the current from the positive plate, by rendering
the zinc a better conductor.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondents I declare that what I claim is:-
Firstly; A secondary battery, in which the stored current of charged positive
plates is discharged, said positive plates being enclosed in a covering of woollen
or other suitable material saturated with the electrolyte and inserted in a casing
of zinc or other suitable metal acting as a negative pole or conductor, sub-
stantially as herein described.
Second; In a secondary battery in which the stored current of charged positive
plates is discharged, the combination with one or more positive plates enclosed
in a covering of woollen or other suitable material saturated with the electrolyte,
of a casing of zinc or other suitable metal acting as a negative pole or conductor,
the metal of the casing being in close contact with the covering of the positive
plate or plates, substantially as herein described.
Third In a secondary battery in which the stored current of charged positive
plates is discharged, the positive plate surrounded by a closely fitting covering of
blanketing woollen or other absorbent material saturated with the electrolyte,
substantially as described.