Improvements in Electrical Accumulators.
Year: 1888

page_text: Date of Application, 28th Sept., 1888
Specification Accepted, 2nd Nov., 1888
COMPLETE SPECIFICATION.
Improvements in Electrical Accumulators.
1, BENJAMIN JOSEPH BARNARD MILLS of the firm of Harris and Mills of 23 South-
ampton Buildings in the County of Middlesex, Patent Agent, do hereby declare the
nature of this invention, a communication to me from abroad by Joseph Barbier of
Villeurbanne, Rhone in the Republic of France, Chemist, and in what manner the
same is to be performed, to be particularly described and ascertained in and by the
following statement, reference being had to the accompanying drawings and to
the figures and letters marked thereon:-
The improvements forming the subject of the present application consist, firstly, in
the employment of a new material in the manufacture of accumulator plates, and,
secondly, in the means of obtaining this product and of giving it the form and qualities
required for its employment.
The new material is known chemically, it is the peroxide of lead, but the particular
mode of production, which is about to be described, gives it new qualities and parti-
cularly that of electric conductibility, without which it is entirely unsuitable for the use
mentioned.
The formation of this material is effected by electro chemical means in the following
manner.
With sheets or plates of lead a body or framework is made having the form of the
plate, or of the block it is desired to obtain, this body or framework is divided prefer-
ably into horizontal strips in such manner as to hold the red lead which will be placed
in the interior.
Figures 1 and 2 of the accompanying drawing show respectively a longitudinal
vertical section, and a vertical cross section of the arrangement of this framework or
body to obtain a rectangular plate; the full lines represent the lead body or framework,
71

page_text: and the dots represent the red lead placed in the interior, which can be held together
if required by means of india rubber rings A. A. A conductor C is soldered to each
of the plates thus formed, and they are then placed in a battery to be submitted to
electrical action.
The minium or red lead, provisionally held by its frames, is not long before it is
transformed into peroxide of lead, in positive plates, and the framework or body itself
receives this transformation. At the end of a certain time there will therefore be
obtained solid and homogeneous blocks of peroxide of lead, of which the special mode
of formation will have developed conducting and other qualities which render it
specially applicable to the purpose for which it is intended as positive electrode.
With respect to negative electrodes, the minium or red lead and the lead framework
or body, will be transformed in the same manner into pure lead.
Plates thus obtained, represented at Figure 5, have no tendency to lose their shape,
nor to crumble, they possess a superior capacity and power to give out electricity, and
give to the accumulator an almost indefinite existence.
It will be readily understood that, by means of frameworks or bodies con-
veniently arranged, there can be obtained plates or blocks of any desired form, for
example, a hollow cylinder, as represented at Figure 6, by the aid of a framework
or body such as that represented at Figure 3, or a solid cylinder, such as that
shown at Figure 7, by means of a framework or body such as that represented at
Figure 4.
These latter forms are very convenient for cylindrical elements in which the hollow
cylinder, Figure 6, is the positive electrode, and the solid cylinder, Figure 7, is the
negative electrode, or vice versa.
The new qualities given to the peroxide of lead by the electro-chemical formation
are not due to its particular state of agglomeration, but are completely inherent to the
substance itself. Thus the plates so formed could be reduced into powder, and be
employed with acidulated water in forming a paste which could be moulded into plates
or blocks having the same properties.
By means of this process peroxide can be industrially prepared with plates or blocks
of minium or red lead of various forms and dimensions supported by suitable frame-
works or bodies. After having been subinitted to electro chemical action these plates
or blocks will be reduced to powder, and will furnish the primitive matter for accu-
mulator plates, to which, by moulding, the desired form and dimension can be given.
Metallic conductors for the electric current will be fixed to these plates during the
moulding, and they will be thus ready to work.
Lead has been indicated for the construction of the provisional frameworks, because
it is itself transformed into peroxide, but a similar result could be obtained with either
a metal or a material capable of dissolving in the bath, zinc for example, the frame-
work or body would thus entirely disappear. Or again, with an inattackable material,
such as carbon, aluminium &c., in this case the framework or body would not be
destroyed and could be repeatedly reused.
In every case above specified the minium or red lead could be replaced by any
other insoluble metallic oxide or salt capable of giving the result desired.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that whai
I claim is :
1. In the manufacture of plates or blocks of electrical accumulators, the employment
of the new material herein described, such material being obtained by an electro
chemical action, transforming into peroxide of lead, minium or red lead placed and
supported in a framework or body of suitable form and material substantially as herein
shown and described.
2. In electrical accumulators the process described whereby plates or blocks for the
same of desired form can be directly obtained by placing minium or red lead in
framework or body of like form, constructed either of lead, which is itself transforme

page_text: into peroxide at the same time as the minium or red lead, or of metal soluble in
the bath, in which latter case, the framework or body would thus entirely disappear..
3. In plates or blocks for electrical accumulators, the process which enables the said
new material to be obtained in powder which is afterwards moulded to the desired
form and adding thereto, during the moulding process, conductors for the electric
current.
B. J. B. MILLS.
By Harris & Mills,
23, Southampton Buildings,
Agents.