Improvements in Electrodes for Secondary Batteries.
Year: 1895

page_text: Date of Application, 5th Jan., 1895
Complete Specification Left, 14th Feb., 1895-Accepted, 13th Apr..
1895
TRUVIDIONAL
Improvements in Electrodes for Secondary Batteries.
I, JACOB WERSHOVEN, of Neumühl-Hamborn, in the Empire of Germany,
Doctor of Philosophy, do hereby declare the nature of this invention to be.as
follows:-
As is well known, secondary-battery plate-electrodes as at present usually
constructed and employed, in which the active material is inserted into gratings or
grooves, possess the great drawback that the active material is very liable to drop
out during the working of the batteries, causing not only short-circuits to be
produced, but the capacity of the batteries to be diminished.
Now, the object of this invention is to obviate these disadvantages, the dropping
out of the active material being prevented by providing the surface of the plates
between the ribs or bars of the support with a metallic protective covering, which
is firmly connected to the said ribs or bars.
Electrodes according to this invention and constructed with supports of various
forms are illustrated in the accompanying drawings.
Figs. 1 and 2 are respectively an elevation and a cross-section of a grating-like
plate-electrode in which the filling material a is protected and held in place by an
electrically formed covering 6 that metallically connects together the several bars c
of the support. The protective covering or coating b between the bars c of the
grating forming the support, is applied after the grating has been filled with the
active material, which may be for instance porous lead powder with or without
neutral admixtures, so as to form between the bars of the grating a porous deposit
of spongy metal which when compressed forms a wall or shell which, though thin
relatively to the bars of the grating, is strong and durable.
When oxides or salts are employed for the active material, it must be metallically
formed before the covering or coating b is formed.
In the case of
The coating or covering 6 may be formed in a variety of ways.
lead secondary batteries, for instance, the filled grating is placed as the cathode
between two lead plates in a solution of an alkali, for instance caustic soda or
caustic potash, of definite specific gravity, and then an electric current, the
strength of which must bear a definite relation to the surface of the anode, is
passed through this cell. The deposit of spongy lead thus produced is rendered
denser by compression.
The metallic covering or coating produces an intimate connexion between the
ribs or bars of the support and the active filling material, and has also the property
Moreover, on
of effectually preventing the said material from dropping out.
account of its porous nature and permeability, it allows the electrolyte to art
uniformly upon the filling material.
After the protective covering has been formed, the plates are at once ready
for use as negative electrodes. In making positive electrodes both the protective
covering and the active filling material are converted into peroxide in the forming
process.
Electrodes thus constructed have also the advantage that even when the
protective covering has become partially worn out, for instance after years of
working, the filling material will still possess sufficient strength to
durability.
ensure

page_text: It is to be understood that by the designation "grating-like plates" in this
Specification are meant plate-electrodes provided with perforations of any kind,
including pocket-like electrodes such as shown in Fig. 3 and grooved electrodes
such as shown in Fig. 4.
One example of the application of this invention, consists in the pocket-like
electrode illustrated in Figs: 5 and 6.
In this case the electrode consists of two cover-plates which are connected
together so as to form a box and between which the active material a is placed.
The plates are formed of bars c after the manner of a grating, and are of such
strength as not to break or warp, whilst the box is formed to receive a considerable
quantity of active material. The space between the bars c is filled up with thin
walls which have a thickness of only a few tenths of a millimetre and which
constitute a protective covering for the filling material a. In order that the
electrolyte may have free access to the active material a, holes d are made through
the electrode. The electrolyte thus comes into contact with the active material
only inside the pocket, whereby the washing or carrying away of the active
material by gases and the consequent dropping out of the said material are entirely
prevented. In this pocket-like electrode the current is conducted or led off
preferably by means of an inner plate e, which is a wide-meshed grating-like plate
of material that is a good conductor of electricity.
Dated this 5th day of January 1895.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.
improvements in Electrodes for Secondary Batteries.
I, JACOB WERSHOVEN, of Neumühl-Hamborn, in the Empire of Germany,
Doctor of Philosophy 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 :-
As is well known, secondary-battery plate-electrodes as at present usually con-
structed and employed, in which the active material is inserted into gratings or
grooves, possess the great drawback that the active material is very liable to drop
out during the working of the batteries, causing not only short circuits to be
produced but the capacity of the batteries to be diminished.
Now, the object of this invention is to obviate these disadvantages, for which
purpose the dropping out of the active material is prevented by providing the
surface of the plates between the ribs or bars of the support with a metallic
protective covering which is firmly connected to the said ribs or bars.
Electrodes according to this invention and constructed with supports of various
forms are illustrated in the drawings filed with my Provisional Specification.
Referring to these drawings,
Figs. 1 and 2 are respectively an elevation and a cross section of a grating-like
plate-electrode in which the filling material a is protected and held in place by an
electrolytically formed covering or coating that metallically connects together
the several bars c of the support. This protective covering or
coating b between
the said bars c, is applied after the grating has been filled with the active material,
which may be for instance porous lead powder with or without neutral admixtures
so that there is formed between the bars of the grating a porous deposit of spongy
metal which when compressed forms a wail or shell which, though thin relatively
to the bars of the grating, is strong and durable.
The covering or coating b may be formed in a variety of ways. In the case of
lead secondary batteries for instance, the filled grating is placed as the cathole

page_text: between two lead plates in a solution of an alkali, for instancer caustic-soda or
caustic potash, of definite specific gravity, and then an electric current, the strength
of which must bear a definite relation to the surface of the anode, is passed
through this cell. The deposit of spongy lead thus produced is rendered denser by
compression.
The metallic covering or coating produces an intimate connection between
the ribs or bars of the support and the active filling material, and has also
the property of effectually preventing the said material from dropping out.
Moreover, on account of its. porous nature, and permeability, it allows the
electrolyte to act uniformly upon the filling material when the electrode is
subsequently used.
After the protective covering has been produced, the plate electrodes are at
once ready for use as negative electrodes. In making positive electrodes both
the protective covering and the active filling material are converted into peroxide
in the forming process.
Electrodes constructed as described have also the advantage that even when the
protective covering has become partially worn out for instance after years of
working, the filling material will still possess sufficient strength to
durability.
ensure
It is to be understood that by the designation "grating-like plates" in this
Specification are meant plate-electrodes provided with perforations or receptacles
of any kind including pocket-like electrodes such as shown in Fig. 3, and grooved
shaped electrodes such as shown in Fig. 4.
Another example of the application of this invention is shown in the construction
of pocket-like electrode illustrated in Figs. 5 and 6. In this case the electrode
consists of two cover-plates which are connected together so as to form a box
and between which the active material a is placed. The plates are formed of
bars after the manner of a grating, and are of such strength as not to break
or warp whilst the box is formed to receive a considerable quantity of active
material.
The space between the bars e is filled up with thin walls which have a
thickness of only a few tenths of a millimetre and which constitute a protective
covering for the filling material a. In order that the electrolyte may also have
free or unobstructed access to the active material, holes d are made through the
electrode. The electrolyte can thus come into direct contact with the active
material only inside the pocket, whereby the washing or carrying away of the
active material by gases and the consequent dropping out of the said material are
entirely prevented. In this pocket-like electrode the current is conducted or led
off preferably by means of an inner plate e, which is a wide-meshed grating-like
plate of material that is a good conductor of electricity.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. A grating like plate electrode for a secondary battery provided with a
metallic deposit which is firmly connected to the ribs or bars of the support and
serves as a protective covering for preventing the active material from dropping
out of the plate substantially as described.
2. A plate electrode of the kind specified in the preceding claim provided with
an electrolytically produced metallic deposit connecting the active filling material
and the ribs or bars of the support, the said metallic deposit being applied after
the said filling material has been inserted in the support and serving as a porous
protective cover for the said filling material substantially as described.
3. A plate electrode of the kind specified in Claim 1, consisting of a lead frame
or support with lead filling material and with an electrolytically deposited porous
lead covering or coating adapted to act as a protective cover for the said filling
material substantially as herein described.

page_text: 4. A plate electrode of the kind specified in Claim 1, made of pocket-shape and
consisting of two grating-like plates connected or combined together so as to forin
a box, with a porous metallic protective covering or coating adapted to support the
active material in place substantially as described.
Dated this 14th day of February 1895.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.