Central Glass Company, Limited

Shiro Moroi

Yasushi Kita

Akira Sakanoue

Minoru Aramaki

Hisaji Nakano

Hishagi Nakano

Hishaji Nakano

Using a positive active material in powder form such as a metal salt or graphite fluoride, an anode for use in an electric cell, and particularly suitable for use in an organic electrolyte cell, is produced by the steps of dispersing the active material, and a conductive material such as carbon powder where necessary, in a solution of an organic polymer used as binder in a suitable liquid, mixing the dispersion with another liquid in which the polymer is substantially insoluble so as to cause precipitation of the polymer in a state intimately mixed with the active material and the conductive material, separating the solid phase mixture from the liquid phase and drying it, and press-shaping the dried mixture into an anode body of a desired shape. By mixing the binder with the active material in this manner, it is possible to obtain an anode body sufficient in mechanical strength and high in electrochemical activity by using only a very small amount of binder.

Method of producing electric cell anode using powdery active material

A graphite fluoride can be produced safely and in high yield on a commercial production scale by a process comprising reacting a carbon material having an average size of 100.mu. to 10 mm with fluorine. Further, when the fluorination reaction is stopped before completion thereof and the graphite fluoride product is subjected to sifting with a sieve to separate a desired graphite fluoride from the raw carbon material remaining unreacted.

Process for producing a graphite fluoride

A method of preparing graphite fluoride such as (CF).sub.n or (C.sub.2 F).sub.n by heterogeneous contact reaction between a carbon material such as graphite or petroleum coke and fluorine gas at about 200.degree.-550.degree. C. In the gas phase of the reaction system, the total concentration of higher fluorocarbons having more than four carbon atoms formed by side reactions is controlled so as not to become above 3% by volume by, for example, condensation or catalytic decomposition of at least a portion of the higher fluorocarbons in the gas flowed out of the reaction chamber for recirculation. Such control is highly effective for prevention of rapid and violent decomposition of the graphite fluoride existing in the solid phase of the reaction system induced by sudden decomposition of the higher fluorocarbons in the reaction system to lower fluorocarbons.

Method of safely preparing graphite fluoride

A method and apparatus for preparation of a graphite fluoride such as (CF).sub.n or (C.sub.2 F).sub.n by heterogeneous contact reaction between a carbon material such as graphite or petroleum coke and fluorine gas at about 200.degree.-550.degree. C. The carbon material in the form of small pieces such as granules or powder particles is kept in a holder having a number of openings so as to form a carbon material layer in the holder, which is placed in a reactor so as to leave gas passages around the holder. With heating, fluorine gas is forcibly passed through the gas passages without agitating the carbon material in the holder. The openings of the holder are shaped and arranged such that the fluorine gas permeates through the carbon material layer in the holder. For example, the holder is an open-type box made of either a wire screen or a perforated metal plate, or a conveyor belt made of a wire screen. This method is effective for prevention of spontaneous decomposition of the formed graphite fluoride attributed to accumulation of the heat of reaction within the reacting carbon material layer and/or mechanical shocks or vibrations to the fluorinated carbon.

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Ube, Japan

Shiro Moroi