IMPROVEMENTS IN AND RELATING TO GALVANIC BATTERIES
Year: 1882

page_text: LETTERS PATENT to Ebenezer Banton Burr, of Walthamstow, and William
Thomas Scott, of the Crown Chemical Works, Stratford, both in the County
of Essex, for an Invention of "IMPROVEMENTS IN AND RELATING TO GALVANIC
BATTERIES"
PROVISIONAL SPECIFICATION left by the said Ebenezer Banton Burr and
William Thomas Scott at the Office of the Commissioners of Patents on the
2nd September 1882.
EBENEZER BANTON BURR, of Walthamstow, and WILLIAM THOMAS SCOTT,
of the Crown Chemical Works, Stratford, both in the County of Essex,
"IMPROVEMENTS IN AND RELATING TO GALVANIC BATTERIES
"
Our Invention relates to galvanic batteries and is partly designed to improve
the working of the apparatus described in the Specification of former Letters
Patent granted to us the 22nd day of December A.D. 1881 No. 5604. The present
Invention is however applicable for other batteries.
It has been found in practice that in the use of the battery described in the
said former Specification, the chemical action set up therein causes a considerable
local action upon the zinc electrodes which has the effect of destroying, or con-
siderably lessening, the electro-motive force of the said battery in a comparatively
short space of time. We have therefore sought to devise means whereby this
injurious action may be prevented.
According to the present Invention we prepare the zinc electrodes in the
following manner, to be used in lieu of the ordinary zinc electrodes heretofore
employed, that is to say, we provide electrodes of zinc which may be of any
suitable or desirable form and dimensions according to the nature of the battery
in, or the use to, which they are intended to be applied. We then provide these
zinc electrodes with a very thin coating of gold, which coating it important
should be effected by electro-deposition; and over the said coating of gold we apply
a thin coating of mercury, which coating we prefer also to effect by electro-
deposition. We have found in practice that a zinc electrode so made gives the
very best results as there is little or no local action of the nature hereinbefore

page_text: mentioned and the said zinc electrode will remain operative for a considerable
length of time.
Although, according to our experience, gold gives the most advantageous results
as the intermediate metal between the zinc and the mercury, other metals may be
used in lieu thereof such for instance as silver, nickel platinum, magnesium,
potassium or iridium, or others, and I may in some cases use graphite for this
purpose.
We also find that in effecting the deposit of gold or other metal upon the
zine, and of the mercury upon the gold or other metal, it is very desirable that
the bath in which the deposit is effected should be heated nearly to boiling point
and kept at this heat during the whole of the time that the electro-deposition is
proceeding.
The ordinary ingredients or substances well known to persons accustomed
to the electro-deposition of metals may be used in the baths but we prefer
to add to the bath in which the first coating, viz, of gold or other metal upon
the zinc, takes place, a small quantity of sulphate of zinc; and to the bath in
which the second coating is effected, viz, of the mercury upon the gold or other
metal, a small quantity of chloride of mercury.
Our Invention will be found very advantageous, not only in a battery constructed
as described in our said former Specification, but also in many other batteries in
which zinc is one of the electrodes of each pair.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Ebenezer Banton Burr and William Thomas Scott in the Great
Seal Patent Office on the 2nd March 1883.
EBENEZER BANTON BURR, of Walthamstow, and WILLIAM THOMAS SCOTT,
of the Crown Chemical Works, Stratford, both in the County of Essex,
"IMPROVEMENTS IN AND RELATING TO GALVANIC BATTERIES
31
Our Invention relates to galvanic batteries, and is partly designed to increase
the efficiency of the apparatus described in the Specification of former Letters
Patent granted to us the 22nd day of December A.D. 1881, Nº 5604.
It has been found in practice that, in the use of the battery described in the
said former Specification, the chemical action set up therein causes a considerable
local action upon the zinc element or electrode, which has the effect of considerably
diminishing the electromotive force of the said battery in a comparatively short
space of time. We have, therefore, devised means whereby this injurious action
will be prevented and the liability of the zinc elements or electrodes to rapid
oxidation and destruction when in use will be obviated.
According to the present invention we prepare the zinc electrodes or elements
in the following manner, to be used in lieu of the ordinary zinc electrodes
heretofore employed, that is to say, we provide pieces of zinc, which may be of
any suitable or desirable form and dimensions, according to the nature of the
battery in which they are to be employed, or the use to which they are intended
to be applied. We cover these pieces of zinc with a very thin coating of gold,
which coating we prefer should be applied by electro-deposition, although any
other suitable means may be employed for the purpose. Over the said coating of
gold we apply, preferably by electro-deposition, a thin coating of mercury
have found in practice that a zinc element or electrode so prepared gives the best
results, as it does not become oxidized, and there is little or no local action; the
said zinc electrodes will, therefore, remain operative for a considerable length of
time and are practically indestructible. In place of the zinc, we may use any other
metal suitable for the positive element of a galvanic battery.
We
Although, according to our experience, gold gives the most advantageous results
as the intermediate metal between the zinc and the mercury, other metals may
be used in lieu thereof, such, for instance, as silver, nickel, platinum, magnesium,
potassium and iridium; and we may, in some cases, use graphite for this purpose.
We also find that, in the electro-deposition of gold or other metal upon the zinc,
and of mercury upon the gold, or other metal, it is very desirable that the bath in
which the deposit is effected should be heated nearly to boiling point and maintained
at this temperature during the whole of the process.
The ordinary ingredients or substances, well known to persons accustomed to the
electro-deposition of metals, may be used in the baths, but we prefer to add,
to the bath in which the first coating (that of gold or other metal upon the zinc)
takes place, a small quantity of sulphate of zinc, and, to the bath in which the
second coating (that of the mercury upon the gold or other metal) is effected,
a small quantity of chloride of mercury.
Our invention will be found very advantageous, not only in a battery constructed
as described in our said former Specification, but also in many other batteries in
which zinc is employed as one of the electrodes.
It will be understood that we may use any required number of such elements
in the formation of a battery, and that they may be of any desired form or
dimensions.

page_text: Having thus fully described our said Invention and the manner of performing
the same, we wish it understood that we claim :-
In, or for, a galvanic battery, an element consisting of a piece of zinc or other
suitable metal coated or covered first with gold or other metal or with graphite,
and then with mercury, substantially as above set forth and for the purpose
specified.
In witness whereof we the said Ebenezer Banton Burr and William Thomas
Scott have hereunto set our hands and seals this twenty sixth day of
February in the year of Our Lord One thousand eight hundred and
eighty three.
EBENEZER BANTON BURR (L.S.)
WILLIAM THOMAS SCOTT (L.S.)