An Improved Electrolytic Solution for Galvanic Batteries.
Year: 1890

page_text: COMPLETE SPECIFICATION.
An Improved Electrolytic Solution for Galvanic Batteries.
1, LOUIS WEIGERT, of 99, Kurfürstenstrasse, Berlin, in the German Empire,
Physician, 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 :-
It is well known that the inconstancy of a galvanic battery, wherein an exciting
fluid prepared from the chlorides of copper, mercury, iron, etc. is employed, arises
from the circumstance that products of a more or less insoluble character are formed
during the chemical decomposition which takes place. These products settle upon
the electrodes, and cause the electro-motive force to rapidly fall off. The result is
that galvanic batteries wherein the usual exciting fluids are employed have not
become generally serviceable for electric lighting without the intervention of
accumulators.
The exciting fluid hereinafter described avoids these disadvantages, inasmuch as
it considerably prolongs the constancy of the current. Further, a galvanic battery
whereir. an exciting fluid prepared in accordance with my invention is employed
possesses the advantage of belonging to the "single fluid" class.
In order to obtain these advantages and to secure complete depolarisation and
constancy of current, I employ an exciting fluid consisting of a concentrated solution
of one or several chlorides (such as of copper, iron, zinc, etc.) in combination with a
salt of mercury.
Such an exciting fluid may be composed of 1,000 parts (by
weight) of sesqui-chloride of iron, 200 parts of chloride of zinc, 75 parts of chloride
of mercury, and 1,000 parts of water. When a mixture of this character is employed,
the amalgam remains preserved on the zinc electrode. Moreover, the oxidizing
influence of the acid upon the chlorides (reduced to chlorine or some other form
during the activity of the battery) brings about a regeneration of the electrolytic
solution.
By the preservation of the amalgam on the zinc electrode, an excessive use of the
zinc is avoided; and, by the above-described method of regeneration, the constancy
of the battery is longer maintained and deposit on the electrodes prevented. Further-
more, the employment of a single exciting fluid simplifies the use of the battery, and
reduces the cost both of preparation and maintenance.
By reason of the greater constancy of the electric current vielded by a galvanic
battery excited as hereinbefore described, it is possible to work electric lamps
directly with steadiness and for comparatively long periods without employing
accumulators.
The above-described effect can also be attained by adding, or substituting for the salt
of mercury, oxidizing agents, such as hypochlorites, by which oxidizing agents the
nascent chlorine regenerates the electrolytic solution by bringing back the chlorine
or other chemical products into the original form of the chlorides.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I claim :-
1. In a galvanic battery, the employment of an exciting fluid consisting of a
concentrated solution of one or several chlorides (such as of copper, iron, zinc, etc.)
in combination with a salt of mercury, substantially as herein described.
2. In a galvanic battery, the employment of an exciting fluid consisting of a
concentrated solution of one or several chlorides (such as of copper, iron, zinc, etc.)
in combination with oxidizing agents, such as hypochlorites, substantially as herein
described.

page_text: 3. In a galvanic battery, the employment of an exciting fluid consisting of a
concentrated solution of one or several chlorides (such as of copper, iron, zinc, etc.)
in combination with oxidizing agents, such as hypochlorites, and a salt of mercury,
substantially as herein described.
Dated this 29th day of March 1890.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.(., Agent for the Applicant.