IMPROVEMENTS IN PRIMARY VOLTAIC BATTERIES
Year: 1884

page_text: We DESMOND GERALD FITZ GERALD, of 6 Akerman Road Brixton in the County
of Surrey, Electrician and THOMAS JOHN JONES, of 12 Princes Street, Hanover
Square, in the County Middlesex, Electrician do hereby declare the nature of
our invention for "IMPROVEMENTS IN PRIMARY VOLTAIC BATTERIES
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement:-
"
and in what
The object of our Invention is to diminish the cost of working primary voltaic
batteries and to obviate the inconvenience and loss of efficiency due to the
"efflorescence" and "creeping" of crystalline salts such as are ordinarily employed
or produced in such batteries. This object we effect by substituting for zinc, as
the positive element of a primary battery, the metal lead in a porous or spongy
condition; the electrolyte being a solution of some acid (such as sulphuric or
phosphoric acid) which forms with lead an insoluble salt from which the metal is
economically recoverable.
In carrying out our Invention we take lead in a state of fine subdivision as
obtained by mechanical, chemical or electro-chemical means and we apply a layer
of this material on one or both sides of a conductive supporting plate, preferably of
lead, perforated with small holes in those portions which are embedded in the
porous lead. By means of a moderate amount of compression the finely divided
lead is caused to adhere to the conductive support which may take the form of a
tang" or tangs, embedded in the porous metal, or even a wire distributed through
the mass of the finely divided lead may be used in lieu of the plate or tang.
Instead of compressing the porous or spongy lead against the support we may
employ elements composed of or coated with porous or spongy lead obtained by
various known processes such as by electro-deposition &c. The porous lead plates
thus produced should be preserved for use under water.
"
When these plates are substituted for zinc elements, in an electrolyte of dilute
sulphuric acid for instance, the porous lead becomes almost entirely converted by
the electrolytic action into insoluble sulphate of lead, a salt having a commercial
value and from which metallic lead is readily recoverable, whilst the production of
any crystallisable salt is avoided so that the battery is rendered exceptionally
cleanly and effective when kept in long continued action.

page_text: These porous lead positive elements may be employed in conjunction with any
suitable negative element such as copper immersed in solution of sulphate of this
metal, or carbon in contact with manganese peroxide.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed we declare that what
we claim is :-
1st A primary battery constructed of a positive element of lead in a spongy or
porous condition, an electrolyte-such as sulphuric or phosphoric acid-which
produces with the lead an insoluble salt of this metal and any suitable negative
element such as copper immersed in a solution of sulphate of this metal, or carbon
in contact with manganese peroxide.
2nd A positive element for primary voltaic batteries constructed of the metal
lead in a spongy or porous condition compressed upon a perforated plate or tang,
support or wire, of conductive material.
3rd The construction of positive elements of primary voltaic batteries by
compressing lead in a spongy state, or in a state of minute subdivision, upon a
supporting plate "tang" or its equivalent of conducting material.
Dated this 28th day of November 1884.