Improvements in the Active Material for Secondary and Primary Batteries.
Year: 1895

page_text: Date of Application, 23rd Apr., 1895
Complete Specification Left, 23rd Jan., 1896-Accepted, 29th Feb., 1896
PROVISIONAL OF FUIFICATION.
Improvements in the Active Material for Secondary and Primary
Batteries.
I, ALEXANDER SCHANSCHIEFF, of Clifton Villa, The Avenue, Upper
Norwood, in the County of Surrey, Electrical Engineer, do hereby declare the
nature of this invention to be as follows:-
This invention relates to the composition and preparation of the paste or active
material for secondary and primary batteries.
The object of my invention is to get a paste of such a character, that the
chemical action of the electrolyte may, penetrate well through the mass of the
paste.
I have previously in my Complete Specification No. 12045 of 1894 described
plates for secondary batteries made by using sugar or treacle with metallic
oxides:-chemical changes taking place in the plates so made, during the
preparation of the plates for work.
My present invention is for treating and preparing the non-metallic portion of
the active material, prior to mixing it with the metallic salts, and the formation
into plates.
If sugar is the material used, I mix the same with a little water (preferably
distilled so as to leave a quantity of the sugar undissolved. I then add strong
sulphuric acid of 1-856 "Baumé" until the carbon is thrown up and the liquid
disappears. Instead of sugar I may use other hydrocarbons as for instance
treacle.
Large vessels should be employed as the solution of sugar increases very largely
in bulk under the action of sulphuric acid.
Voluminous fumes of sulphuric acid are at the same time given off. The carbon
thus prepared must be kept for a day or so or until it has cooled and then mixed
with metallic salts."
When the paste is required I thoroughly mix one part by volume of the said
carbon with say 2 parts by volume of appropriate metallic salts according to the
nature and construction of the battery or whether a positive or negative element
is required. I am however not limiting myself to the above proportion. The
mixture having cooled I add a solution of sulphuric acid in water and thus form it
into paste of the consistency of putty. The paste is then ready for use in
secondary batteries of any form or construction.
As applied to a single liquid primary battery and instead of pulverized coke
which has heretofore been used 1 advantageously apply the aforesaid carbon mixed
with heavy salts such as peroxide of lead, peroxide of manganese or basic sulphate
of mercury, (turpat mineral) to the positive plate, and tie parchmentized paper
over it with cotton. Or in a double liquid battery I surround the positive element
in the porous pot with the aforesaid carbon.
The paste hardens quickly, is not easily washed out or disintegrated is very
porous and gas absorbing and the conductivity of the plates is also considerably
increased.
Dated this 92nd day of April 1805

page_text: COMPLETE SPECIFICATION.
Improvements in the Active Material for Secondary and Primary
Batteries.
I, ALEXANDER SCHANSCHIEFF, of Clifton Villa, The Avenue, Upper
Norwood, in the County of Surrey, Electrical Engineer, do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described in and by the following statement :-
This invention relates to the composition and preparation of an active material
paste for secondary and primary batteries.
The object of my invention is to produce a paste of great efficiency as active
material, that is to say, one which retains the electrical charge for a long time,
which has great capacity and conductivity and which is very porous, hard,
coherent and gas absorbing. The manufacture of it is also cheap, requiring no
pressure or furnace heat.
I first produce a carbon by carbonizing Demerara sugar, treacle or other
suitable hydrocarbon by means of sulphuric acid taking care by properly
apportioning the ingredients to produce the carbon dry without having any free
liquid in it. I may thus mix 100 parts by weight of the sugar with about
30 parts of the water by preference distilled whereby a small part of the sugar
remains undissolved. I then add strong sulphuric acid of 1-856 Baumé, about
50 parts by weight of the sugar solution to 35 parts of the sulphuric acid, until
the carbon is thrown up and the liquid disappears, fumes of sulphuric acid
passing off while the bulk of the material increases very largely, wherefore large
vessels should be employed. The carbon thus produced is of a crystalline
structure; it must be kept for a day or so or until it has cooled, and is then mixed
with the metallic oxide or salt according to the nature and construction of the
battery or whether a positive or negative element is required.
When required, for instance, for a secondary battery, I may thus employ about
one volume of the carbon to two of the oxide (minium or litharge). Or if !
desire a large discharge I may use one of carbon to three of the oxide. But I
am not limiting myself to the above proportions. The mixture is left to cool,
say for about 24 hours. Some parts of the minium and of the litharge are
converted into carbonate of lead heat being evolved. The sulphuric acid present
in the above carbon acts on the nonconverted particles of the minium, oxydizing
the same, the paste assuming a rich purple colour. The litharge is at first
oxydized and then carbonized and ultimately assumes a whitish grey colour.
I then add so much of a solution of sulphuric acid in water, say 1.1° Baumé,
as to make it into a dough of the consistence of putty. The paste is then ready
for use.
As applied to a single liquid primary battery and instead of pulverized coke
which has heretofore been used I advantageously apply the aforesaid crystalline
carbon for mixing with heavy oxides or salts, such as peroxide of lead, peroxide
of manganese or basic sulphate of mercury ("turpat mineral") to the positive
plate, and tie parchmentized paper over it with cotton. Or in a double liquid
battery I surround the positive element in the porous pot with a paste made with
the aforesaid carbon.
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 :-
An active material paste made by carbonizing sugar or other suitable hydrocarbon
by means of sulphuric said showch hand and co

page_text: has cooled mixing it with the oxide or salt and finally after the mixture has cooled
mixing it with a sulphuric acid solution to form a dough of the consistence of
putty, all substantially as described.
Dated this 23rd day of January 1896.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.