IMPROVEMENTS IN SECONDARY BATTERIES OR ACCUMULATORS
Year: 1883

page_text: LETTERS PATENT to Farnham Maxwell Lyte of Putney in the County of
Surrey for an Invention of IMPROVEMENTS IN SECONDARY BATTERIES OR
ACCUMULATORS
PROVISIONAL SPECIFICATION left by the said Farnham Maxwell Lyte at
the Office of the Commissioners of Patents on the 20th November 1883.
FARNHAM MAXWELL LYTE of Putney in the County of Surrey, "IMPROVEMENTS
IN SECONDARY BATTERIES OR ACCUMULATORS,"
This Invention relates in part to improvements in the secondary battery or
accumulator described in the Provisional specification filed by me on the 13th July
last (No 3452.).
"
According to my former Invention the active material used in the battery
consisted of a number of studs, prisms, or short bars of spongy lead having flanges,
collars, or other projections, these being set in supports composed of metallic
sulphides with or without an excess of sulphur. I have since found that these
supports may with advantage be made of lead or pewter, antimonial lead or type
or Britannia metals placing them back to back (as described in my above mentioned
specification) with or without a central plate of some conducting material placed
between them, against which the flat ends of the studs or prisms rest, and are
pressed closely into contact.
I also propose to construct a battery with a central plate composed of lead,
antimonial lead, pewter, Britannia or type metals, foil, gauze, net or tissue of
sufficiently stout silver or platinum as follows. I make by compression or fusion
from some insoluble salt of lead such as the chloride, the sulphate, the phosphate,
the chromate or the oxalate for instance (by preference the one first mentioned)
square bars, elongated prisms, truncated elongated prisms, or semi-cylindrical rods,
and place them with their largest flat sides against the central plate in a mould
constructed for the purpose. I prefer the conical shapes above mentioned, turning
the larger side downwards, as I thus promote holding into electrical contact with
the central plate. I bind these bars to the plate by pouring or moulding round
them some material which need not be a conductor (pitch or bitumen or some

page_text: fused gum resin insoluble in water or dilute acid for instance) and I leave so as to
be exposed to the acid in which it is immersed, a sufficient surface of the part
opposite the side touching the plate.
If a central plate is used in the first case above mentioned, it being a conductor,
the two side plates which hold the active material in contact with it need not
either be made of a conducting material, but may be made of guttapercha, ebonite,
glass, porcelain or even varnished wood, cork, or papier machè. It may also have
studs or short wires connected with it and corresponding with each hole and
passing into the active material or into the insoluble or sparingly soluble lead salt
which is afterwards converted into it so as to produce better contact and less
resistance. This central plate may be of one of the metals already mentioned.
It is to be understood that these prisms, strips or bars may be reduced into the
form of spongy lead either before or after being placed in contact with the central
plate. Against this also they may be held by means of a grating of lead cast or
made separately and specially to fit them. If the plate has holes pierced through
it or be of wire net or gauze, it may be imbued on either or both of its sides with
the active material, the reduced lead in the latter case on the opposite sides of the
plate becomes locked or joined together, thus promotes holding. But this central
plate may be made without holes and a layer of the active material placed on it.
On either or both faces of such a plate may be placed if desirable a reticulated
tissue made of horse hair or of some wire capable of resisting decomposition by
peroxide of lead and acid, or of string, woven glass, perforated ebonite, perforated
sheet lead, or of a perforated plate of one of the alloys or metals above mentioned,
or a thin porous plate may be used for this purpose. This central plate may also,
if advisable, be covered with studs or be corrugated so as to promote the adhesion
of the lead or lead compound with which it is covered. The central plate may
also, where requisite, be surrounded with a frame of some baser metal, or of wood,
or of some suitable substance like ebonite varnished or enamelled if necessary to
protect it from the action of the acid. It may also be made to project or rise out
of the liquid in which it is placed so as to facilitate the adaptation of the conducting
wires.
I find also that the sulphates or the acid sulphates of one of the alkaline metals
or of ammonium, (sulphate or bisulphate of soda for instance) also phosphoric
and oxalic acids or binoxalates may be dissolved in water and the solution
advantageously employed in lieu of the dilute sulphuric acid usually employed as
an electrolytic fluid

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Farnham Maxwell Lyte in the Patent Office on the 20th May 1884.
FARNHAM MAXWELL LYTE of Putney in the County of Surrey. "IMPROVEMENTS
IN SECONDARY BATTERIES OR ACCUMULATORS
"
This Invention relates to improvements in the secondary battery or accumulator
described in the Specification of Letters Patent granted to me and bearing date the
13th July 1883 (N° 3452)
According to the Invention there described the electrode is constructed of a pair
of juxtaposed plates made of some conducting material and having studs, prisms
or bars of active material fitted in holes therein, said studs prisms or bars having
collars or projections or being of such form as to be retained in the plates and
project from the surface thereof when the latter are secured together back to back.
According to my present Invention I construct an electrode in a similar manner
but instead of supporting the studs &c of active material in a pair of juxtaposed
plates made of conducting material I employ plates or supports of non-conducting
material in which the studs are held as described in the Specification of my former
Patent, and interpose between these supports a plate or layer of lead or of
sufficiently stout silver or platinum foil, gauze or wire net or other suitable.
conducting material, to which the conducting wires are attached. The side plates
or supports may be made of gutta percha, ebonite, glass, porcelain, cork or other
suitable material.
In carrying out my Invention, I produce the studs bars or prisms by compression
or fusion from some insoluble salt of lead, such as the sulphate, the chloride, the
phosphate or the chromate (by preference the one first mentioned) and place them
with their largest flat sides against the central plate in a mould constructed for the
purpose. They are then secured to the plate by placing them in contact with said
plate and pouring or moulding round them some material which need not be a
conductor (pitch or bitumen or some fused gum resin insoluble in water or dilute
acid for instance) leaving, so as to be exposed to the electrolyte, a sufficient surface
of the part opposite the side touching the plate. I prefer the conical shapes above
mentioned in order to promote holding into electrical contact with the central plate.
The active material may also have studs or short wires passing transversely
through it (or through the insoluble or sparingly soluble lead salt which is afterwards
converted into it) and also through the intermediate plate so as to produce better
contact and less resistance.
•
It is to be understood that these prisms, strips, or bars may be reduced into the
form of spongy lead either before or after being placed in contact with the central
plate and they may be more securely held in place by means of a grating of lead
cast or made separately and specially to fit over them and permit the studs,
prisms, &c, to project through the apertures in said grating.
The central plate may, if of metal, have holes through which studs of the active
material may extend, but this central plate or conducting layer may with advantage
be of wire net or gauze, in which case it may be imbued on either or both of its
sides with the active material in such manner that the reduced lead on the opposite
sides of the plate becomes locked or joined together. The central plate may also,
where requisite, be surrounded with a frame of some baser, metal, or of wood, or
of some suitable substance like ebonite varnished or enamelled if necessary to
protect it from the action of the acid.
I find also that the sulphates or the acid sulphates of one of the alkaline metals
or of ammonium (sulphate or bi-sulphate of soda for instance) and also phosphoric

page_text: acid may be dissolved in water and the solution advantageously employed in lieu
of the dilute sulphuric acid usually employed as an electrolytic fluid.
Having described the nature of my Invention and the manner of performing
the same, I declare that what I claim as my Invention to be protected by the
hereinbefore in part recited Letters Patent is.
1st Constructing a secondary battery electrode of a pair of plates serving as
supports for studs, prisms, or bars of active material and with an intermediate plate
or layer of some conducting material against which the active material is held in
contact, substantially as specified.
2nd In a secondary battery electrode constructed as specified in Claim 1, the
method of causing the studs or bars to adhere securely to the central conducting
plate by moulding or pouring around them some suitable material, substantially as
specified.
3rd In a secondary battery electrode constructed as above described, the
employment of a lead grating for maintaining the studs, prisms, or bars in contact
with the central conducting plate as specified.
In Witness whereof I the said Farnham Maxwell Lyte have hereunto set my
hand and seal this twentieth day of May, A.D. 1884.