Improvements in the Manufacture of Plates for Secondary Electrical Batteries.
Year: 1895

page_text: Date of Application, 27th June, 1895-Accepted, 27th July, 1895
JUMI DEI DI MUIFICATION.
Improvements in the Manufacture of Plates for Secondary
Electrical Batteries.
I, CARL HUGO WEISE, of Poessneck in the German Empire, Engineer, 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:
This invention relates to the manufacture of plates for use in secondary electrical
batteries.
In a plate constructed according to this invention the lead oxide is contained
within a frame and between perforated plates or sheets. The oxide is hardened by
the passage of a current and still further by its tendency to swell within the
enclosed space.
In order that my invention may be more clearly understood I have hereto
appended a sheet of drawings to which I refer hereinafter.
Figure 1 represents a cross section of part of the frame of the plate.
Figure 2 shows a similar section of part of the frame and part of the attached
side plates.
Figure 3 illustrates the finished plate in elevation.
Figure 4 shows the frame in end elevation.
Figure 5 is a section of part of the plate containing the oxide.
The method of constructing one of the improved plates is as follows:-On one
side of the frame b, which is preferably approximately rectangular, is placed a thin
sheet of lend or other suitable material d which may be easily perforated. Over
this is placed a perforated press plate a which is secured in the frame b by bending
up the edges or flanges c as is clearly shown in Figures 2 and 5. The frame is
then laid flat with the side plates underneath and is filled with the soft paste of
lead oxide. Similar plates d and a are then placed on the upper side of the frame
and are similarly secured. The frame is of lead or of a suitable alloy.
After the frame has been filled and closed, pins or studs of cellulose are passed
into the perforations e of the plates a and are forced through the plates d and the
contained mass of lead oxide which is prevented from escaping by the close fit of
the plates d upon the pins l.
The plate is then immersed in a bath of dilute sulphuric acid and has an electrical
current passed through it, the immediato effect of which is to harden the surface of
the lead oxide, which hardening ultimately extends throughout the substance of
the mass of oxide and is further assisted by the compression of the mass as it tends
to expand within the closed space. A good contact is also ensured between the
plates a and the frame b, upon the latter of which may be formed or to which may
be attached any desired or suitable terminal or terminals.
The plate is now removed from the bath and dried in the open air when the
cellulose pins will be found to be completely destroyed thus leaving openings or
passages through the completed plate. These channels or passages offer great
advantages in use as they do not impede the circulation of the electrolyte.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. The method of manufacturing plates for secondary electrical batteries
substantially as hereinbefore described.

page_text: 2. A plate for use in a secondary electrical battery constructed substantially as
herein before described and as illustrated by the accompanying drawings.
Dated this 26th day of June 1895.
W. E. HEYS & SON,
Agents for the Applicant.