Improvements in and relating to Voltaic Cells.
Year: 1891

page_text: Date of Application, 25th Apr., 1891-Accepted, 30th May, 1891
COMPLETE SPECIFICATION.
Improvements in and relating to Voltaic Cells.
I, GEORG WESTER, of 42, Göthestrasse, Munich, in the Kingdom of Bavaria,
Manufacturer, do hereby declare the nature of this invention and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement :-
The object of my invention is to construct a voltaic cell which shall have the
power of producing for a long period in a closed circuit a current of practically
uniform strength.
A cell arranged according to my improved method is represented in the accom-
panying drawing and comprises a glass jar a having a square base similar to a
Leclanché cell; the same containing a vessel of porous porcelain. The lower
part of the vessel 6 is saturated, for about one-third of the total height, with
paraffin; the absorbent power of this portion being thus neutralized. The upper
part of the vessel b, which comprises about two-thirds of the total height of the
vessel, is saturated with an aqueous solution of ammonia (NH). After the pores
of the material composing the upper part of the vessel b have become charged
with a portion of this solution, the remainder of the solution is poured off and
replaced by a saturated solution of sulphate of copper (SO, Cu 5 H₂O), which
enters the pores in the upper part of the vessel and combines with the ammonia
already present therein, forming a new combination of sulphate of ammonia and
copper (SO, Cu 4 [NH3] H, O). After the upper part of the porcelain vessel has
been thus treated, the solution of sulphate of copper is poured off and the porcelain
vessel dried.
The exciting fluid in the vessel 6 consists of a solution of sulphate of copper.
The electrode e is made of copper, is S-shaped, and is placed in the vessel b.
Outside this vessel, there is a zinc electrode f, which is in the form of a rod and
stands in the glass jar a. The latter is filled with chemically pure sal-ammoniac
powder and water.
The pores of the porcelain vessel being closed in the manner above described, a
diffusion of the solution of sulphate of copper in the porcelain vessel and of the
solution of sal-ammoniac in the glass jar cannot take place. The reason of this is
that the combined sulphate of ammonia and copper (SO, Cu 4 [NH] H₂O) pre-
sent in the pores of the vessel b is insoluble either in the solution of sulphate of
copper or in the solution of sal-ammoniac. In working, the combined sulphate of
ammonia and copper (SO, Cu 4 [NH3] H, O) serves as a conductor.
One result of treating the inner porcelain vessel in the manner above described
is that deposit upon the zinc of oxide of copper is prevented.
In testing a cell constructed as described above, the foliowing results have been
observed :-
Electromotive force
Strength of current
Resistance
0-812 volts,
0.203 ampères,
4 ohms.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I claim :-

page_text: the inner or porcelain vessel containing a solution of sulphate of copper and the
outer vessel or glass jar a solution of sal-ammoniac, substantially as herein
described.
3. For use in a voltaic cell, an inner vessel of porcelain, the pores in the lower
part of which are filled with paraffin and the pores in the upper part with a com-
bination of sulphate of ammonia and copper.
4. The herein described method of preparing the inner vessel of a voltaic cell.
whereby the pores in the lower part of the vessel are saturated with paraffin, the
pores in the upper part with an aqueous solution of ammonia, a solution of sulphate
of copper being afterwards allowed to combine with the solution of ammonia con-
tained in the pores of the upper part, and the vessel being ultimately dried.
Dated this 25th day of April 1891.
G. G. M. HARDINGHAM,
Per J. W. S.,
191, Fleet Street, London, E.C., Agent for the Applicant.