JP3715979B2 - Improved fluorinated carbon for metal / fluorinated carbon batteries - Google Patents

Description

  The present invention relates to improved fluorinated carbon (CFx) materials and mixtures thereof useful in the manufacture of batteries. The present invention relates to a novel current producing battery. More particularly, the present invention relates to an improvement in current production cells in the form of an alkali metal anode, a cathode of a fluorinated carbon material and an electrolyte. More particularly, the present invention relates to a novel cathode composition comprising fluorinated carbon made by mixing fluorinated anisotropic carbon and fluorinated isotropic carbon, wherein the anisotropic composition is anisotropic. Carbon is carbon fiber, and isotropic carbon is graphite. Such compositions are useful as cathode active materials in non-aqueous batteries having an active metal anode such as lithium, sodium or potassium. This novel composition has a higher specific capacity and higher discharge rate capability than conventional industrial products based on fluorinated petroleum coke or similar materials. Furthermore, cathodes made with this composition do not swell during discharge (the cathode volume does not increase) compared to cathodes made from conventional fluorinated carbon or simply made from fluorinated carbon fibers. By using a fluorinated carbon material that does not swell during discharge, battery manufacturers can increase the amount of active material per unit volume, thereby increasing the overall energy and life of the battery. The invention also relates to a biomedical device driven by a non-aqueous lithium battery mixed with a fluorinated carbon material that does not swell during battery discharge. The present invention also generally relates to an electrochemical cell used to drive an implantable medical device.

  Active materials for high performance battery anodes, when used in combination with a suitable cathode, high electromotive force, high open circuit voltage, and even small overvoltage during discharge, good flatness of discharge curve and unit volume It is typically required to have a large per capita discharge capacity. Furthermore, the active material is required not to decompose or dissolve in the battery electrolyte and must be stable over time.

  Fluorinated carbon materials having the general chemical formula (CFx) n, where x is a number between 0 and 2 and n is an unconstant greater than 2, are known to be useful as cathode materials for lithium batteries. And has been used for lubrication. Hereinafter, (CFx) n is abbreviated as CFx for the purpose of this specification. Fluorinated carbon is prepared by the reaction of fluorine gas with many of the various forms of carbon including graphite, petroleum coke, coal coke, carbon black or carbon fiber. The reaction between fluorine and carbon is carried out at a temperature in the range of 250 ° C. to 600 ° C., and the reaction time is usually in the range of 1 to 24 hours.

  It has been known for some time that fluorinated carbon compounds can be used as active cathode materials in non-aqueous batteries. Special attention has focused on systems using this cathode material, non-aqueous electrolytes and highly active metal anodes such as lithium or sodium. As an example of such a system, Brawell et al., In US Pat. No. 3,514,337, discloses a high energy density battery consisting of CFx with x in the range of 0.1 to 0.28. In US Pat. No. 3,536,532 to Watanabe et al., The patentee describes a high energy density battery using CFx with x ranging from 0.5 to a maximum of 1. Fluorinated carbon battery materials prepared from crystalline carbon (eg, graphite) exhibited higher energy density and improved discharge performance compared to Brawell's described materials. Another disclosure of Watanabe et al. In US Pat. No. 3,700,502 is a CFx type fluorinated element in which x is in the range of greater than 0 to 1 and is prepared from a carbon source such as charcoal, activated carbon or coke. A high energy density system using carbon is described. These batteries showed a long life due to the stability of the fluorinated carbon in the electrolyte. In both of these systems, the electrolyte was an organic solvent (ie, propylene carbonate, etc.) and a non-aqueous solution of lithium perchlorate. The anode active material is an alkali metal such as lithium or sodium.

  Another battery of fluorinated carbon having a value of x greater than 1 and up to 2 and including 2 is described in Gunter US Pat. No. 3,892,590. The material of this patent is described as exhibiting a higher energy density than the prior art due to the increased fluorine content.

  In US Pat. No. 4,271,242, Toyoguchi et al. Disclosed the use of fluorinated carbon obtained by fluorinating carbon having a lattice constant of 3.40 to 3.50 A on its (002) plane. Yes. The carbon is selected from petroleum coke and coal coke, and the resulting battery has excellent discharge and shelf life characteristics. The fluorinated carbon materials described in this patent are generally accepted as an industry standard for lithium batteries using fluorinated carbon cathodes, and such materials are widely used in the industrial production of batteries.

  In the Russian Electrochemical Society Vol. 36, No. 12, 2000, p. 1325, Zolin and Smirnov evaluated the performance of various types of fluorinated carbon including fluorinated carbon black, fluorinated coke and fluorinated carbon fibers. The results show that fluorinated coke is superior to fluorinated carbon fiber. However, these authors use a mixture of fluorinated carbons produced from anisotropic and isotropic carbon, where the anisotropic material is carbon fiber and the isotropic material is graphite. Did not recognize the benefit of that.

  It is further known that a wide range of implantable electronic devices are provided for surgical implantation in humans or animals. A common example is a cardiac pacemaker. Other examples of implantable devices include devices for stimulating or sensing parts of the brain, spinal cord, muscle, bone, nerve, gland or other body organ or tissue. Porting devices are becoming more and more complex and typically include sophisticated data processing hardware such as microprocessors, storage devices, or other large scale integration (LSI) devices. The device is often designed to send a signal to a remote sensing device. The demand for improved power batteries to drive implantable devices has increased greatly, with the need for implantable devices to become more sophisticated and in particular to reliably signal external sensors. Of course, there are limitations to the design and construction of power cells for use in implantable devices, particularly with respect to their size and shape. In addition, power cells for implantable devices must be reliable and able to supply adequate amounts of current and voltage over a long period of time.

  Therefore, the present inventors have conducted extensive research to develop a fluorine-type active material for a high performance battery cathode, and as a result, almost meet the above requirements for a high performance battery cathode active material. We have found an active material for the cathode that not only fully satisfies but also superior to the conventional active material for the cathode in various performances for the battery.

  The prior art describes a cathode composition consisting of a mixture of fluorinated carbon made from anisotropic and isotropic carbon, where the anisotropic material is carbon fiber and the isotropic material is graphite. not exist. Applicants have discovered that such a mixture provides a significant improvement in discharge characteristics over prior art fluorinated carbon electrode compositions when used as an active cathode material in non-aqueous batteries. The prior art also does not describe the use of batteries containing the novel fluorinated materials of the present invention in biomedical applications including implantable devices.

Object of the invention

Accordingly, one main object of the present invention is to provide a novel composition of fluorinated carbon having superior properties for industrial applications.
Another object of the present invention is to provide a fluorinated carbon composition useful as a cathode material.
Yet another object of the present invention is to provide a composition comprising fluorinated carbon made from a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon.
Yet another object of the present invention is to provide a cathode material consisting of fluorinated carbon made from a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon.
Still another object of the present invention is to produce a mixture of fluorinated isotropic carbon and fluorinated isotropic carbon in which the anisotropic material is carbon fiber and the isotropic material is graphite. To provide a composition comprising a selected fluorinated carbon.
Still another object of the present invention is to produce a mixture of fluorinated isotropic carbon and fluorinated isotropic carbon in which the anisotropic material is carbon fiber and the isotropic material is graphite. A cathode composition comprising the fluorinated carbon produced.

Another important object of the present invention is the fluorinated anisotropic carbon and the fluorinated isotropic carbon in which the alkali metal anode and the anisotropic material are carbon fibers and the isotropic material is graphite. Is a non-aqueous battery comprising a cathode composition made of fluorinated carbon made of
A further important object of the present invention is to provide a biomedical and implantable device using the battery of the present invention.
These and other objects and features of the invention will become apparent to those skilled in the art from the following detailed description.

Summary of invention

The present invention relates to a composition of matter comprising a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon.
The present invention provides that the fluorinated isotropic carbon is present in an amount of 0.1% to 99.9% and the fluorinated isotropic carbon is 0.1% to 99.9%. It also relates to a composition of matter consisting of a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon present in an amount.

The present invention further includes (a) an anode having an electrochemically active metal as an active material, (b) a non-aqueous liquid electrolyte, and (c) fluorinated anisotropic carbon as its main active material. And a high energy density battery comprising a cathode comprising a mixture of fluorinated isotropic carbon.
The present invention also provides an electrochemically active cathode composition comprising a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon and an effective amount of a conductive material.
The present invention provides that the fluorinated isotropic carbon is present in an amount of 0.1% to 99.9% and the fluorinated isotropic carbon is 0.1% to 99.9%. There is also provided an electrochemically active composition comprising a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon present in an amount and an effective amount of a conductive material.

  The present invention further includes (a) an anode having an electrochemically active metal as an active material, (b) a non-aqueous liquid electrolyte, and (c) fluorinated anisotropic carbon as its main active material. There is also provided a biomedical implantable device driven by a battery comprising a cathode comprising a mixture of fluorinated and fluorinated isotropic carbon.

  The present invention relates to a fluorinated carbon produced by mixing a fluorinated anisotropic carbon and a fluorinated isotropic carbon in which the anisotropic carbon is carbon fiber and the isotropic carbon is graphite. A novel cathode composition comprising: This novel cathode composition is then used in high energy density non-aqueous batteries, which exhibit excellent electrochemical properties. This novel cathode composition makes it possible to provide a novel high energy non-aqueous battery consisting of an anode, an organic electrolyte solution and a cathode. The cathode composition of the present invention, when used in combination with a lithium anode, minimizes and even eliminates battery swelling behavior.

  In the practice of the present invention, a novel cathode composition comprising fluorinated carbon is made by thoroughly mixing fluorinated anisotropic carbon and fluorinated isotropic carbon. This mixture contains fluorinated carbon made from 0.1 wt% to 99.9 wt% anisotropic carbon and fluorine made from 0.1 wt% to 99.9 wt% isotropic carbon. Carbonized carbon may be included. More preferably, the mixture may comprise fluorinated carbon made from 60% to 90% by weight anisotropic carbon and the remainder (10% to 40% by weight) made from isotropic carbon. Fluorinated carbon. More preferably, the mixture may comprise fluorinated carbon made from 70% to 95% by weight anisotropic carbon and the remainder (5% to 30% by weight) made from isotropic carbon. Fluorinated carbon.

  Fluorinated carbon made from anisotropic carbon is preferably made by fluorination of carbon fibers, most preferably by fluorination of carbon fibers made by carbonization of viscose rayon polymer fibers or fabrics. Fluorinated fibers are produced by reacting carbon fibers with fluorine gas at temperatures up to 600 ° C. and reaction times of 1 to 24 hours. After fluorination, the fibers are crushed and sieved to a powder having an average particle size in the range of 4 to 15 microns and a maximum particle size of 45 microns.

  The fluorinated carbon made from isotropic carbon is preferably made by fluorination of natural graphite or synthetic graphite, most preferably by fluorination of natural graphite. These fluorinated carbons are made by reacting natural or synthetic graphite with fluorine gas at temperatures up to 600 ° C. and reaction times of 1 to 24 hours. The starting carbonaceous material (natural graphite or synthetic graphite) is ground prior to fluorination, and the resulting fluorinated carbon must have an average particle size in the range of 4 to 15 microns and a maximum particle size of 45 microns or less. .

  Prior to assembly into an electrode for incorporation into an electrochemical cell, the novel fluorinated active material of the present invention is preferably mixed with a conductive additive. Suitable conductive additives include acetylene black, carbon black and / or graphite. Metals such as powdered nickel, aluminum, titanium and stainless steel are also useful as conductive diluents when mixed with the active materials listed above. The electrode further comprises a binder material which is preferably a fluororesin powder such as powdered polytetrafluoroethylene (PTFE) or powdered fluorinated polyvinylidene (PVDF). Additional active materials useful in the electrochemical cells according to the present invention include silver vanadium oxide, manganese dioxide, lithium cobalt oxide, copper sulfide, iron sulfide, iron disulfide, copper vanadium oxide, and mixtures thereof. Preferred cathode active mixtures consist of fluorinated anisotropic carbon and a mixture of fluorinated isotropic carbon and PTFE in combination with acetylene black and / or graphite.

  The electrodes of the present invention using the novel fluorinated compositions of the present invention can be made according to Shea US Pat. No. 4,556,618. For example, in the preparation of an electrically active fluorinated carbon electrode, the first component consisting of a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon, preferably a small amount of conductivity enhancing material and polytetrafluoro The active cathode material with the addition of a fibrillatable polymer such as ethylene is subjected to a shearing process by dry processing. This converts the component into a material composed of discontinuous fibers throughout the intimate mixture of active material (conductive carbon) components. These materials are first mixed together in a mixer, such as a Banbury mixer or ball mill, and then processed, for example, in an extruder to form a molded electrode article. Alternatively, the components may be mixed together and processed in various orders depending on the desired final electrode geometry and the equipment used to impart porosity to the mixture. During processing, the mixture is completely made up of a suitable liquid pore former that can be easily removed without leaving a detrimental effect on the conditions of the appropriate alcohol / or mixture, for example an isopropanol-water mixture or a molded article. Moistened. Suitable pore formers are generally those which can be vaporized in a conventional manner at a temperature of 50 ° C to 250 ° C, preferably 70 ° C to 150 ° C. By removing the pore former, the precursor electrode composition is converted to the desired electrode system. Converting the fibrillatable polymer to the desired fiber conditions is advantageously done in situ. In-situ conversion means fibrillation in the presence of one of the components of the system, for example the active material.

  The electrode system or precursor electrode composition is formed as pellets, which can be converted to the desired shape of electrode by conventional polymer processing techniques such as extrusion, mold, blow molding or combinations thereof. As indicated above, by appropriate selection of processing methods, the ingredients are processed from a mixture of dry powders, then completely wetted with a pore-forming liquid and cast directly into a sheet or rod. The pore-forming volatile liquid is conveniently extracted during the process of molding the components into the desired shape of the electrode. The thickness of the sheet or bar can be varied and the electrode material can be produced directly as a flexible sheet or film. Alternatively, for example, it can be pelleted, the pellets extruded and blown into a film, or the pellets can be injection molded into a film.

  Typically, a suitable electrode system can be made about 1 to several hundred mils thick. The porosity and conductivity of the electrode system can be adjusted, for example, by appropriate use of pore formers and processing parameters. The bonded electrode composition can be immediately processed or stored and then completely wetted with the pore-forming liquid, which is removed during the electrode molding process or, for example, by controlled heating. The electrodes can be flexible films of the desired thickness, which can be easily combined with current collectors such as conductive films, wire screens or expanded metals.

  The present invention also includes (a) an anode electrode containing an electrochemically active metal as an active material, (b) a non-aqueous liquid electrolyte, (c) fluorinated anisotropic carbon and fluorinated isotropic A high energy density battery comprising a cathode electrode containing a mixture of carbon as a main active material is provided.

  Highly active anodes suitable for use in non-aqueous systems with the novel cathode composition according to the present invention may be consumable metals such as aluminum, alkali metals, alkaline earth metals and alkali metals or Alkaline earth metal alloys are included. The term “alloy” as used herein and in the appended claims is intended to include mixtures, solid solutions such as lithium-magnesium, and intermetallic compounds such as lithium monoaluminide. . Preferred anode materials are lithium, sodium, potassium, calcium, magnesium, and alloys thereof. Of the above preferred anode materials, lithium appears to be the most preferred, which is the highest energy in the group of suitable anodes, besides being a ductile metal that is easily incorporated into batteries. This is because it has a weight ratio.

  Furthermore, the electrochemical cell of the present invention includes a non-aqueous ion conductive electrolyte that serves as a medium for ion transfer between the anode and cathode during the electrochemical reaction of the cell. Electrochemical reactions at the electrodes include reactions that convert ions moving from the anode to the cathode into an atomic or molecular state. That is, the non-aqueous electrolytes suitable in the present invention are substantially inert to the anode and cathode materials, and they exhibit the physical properties essential for ion transport, namely low viscosity, low surface tension and wettability.

  Organic solvents are used in the manufacture of the electrolyte and are well known to those skilled in the art. Examples of such a solvent include the following types of compounds. Lactones, alkylene carbonates, lactams, polyethers, cyclic ethers, cyclic sulfones, dialkyl sulfites, monocarboxylic esters, and alkyl nitriles. Typically preferred solvents in the above categories include γ-butyrolactone, propylene carbonate, N-methylpyrrolidone, 1,1- and 1,2-dimethoxyethane, tetrahydrofuran, methyltetrahydrofuran, sulfolane, dimethyl sulfite, diethyl Examples include sulfites, ethyl or methyl acetate, methyl formate, and acetonitrile.

  Other preferred solvents include sulfolane, 3-methylsulfolane, γ-valerolactone, crotononitrile, nitrobenzene, 1,3-dioxolane, 3-methyl-2-oxazolidone, ethylene carbonate, ethylene glycol sulfite, dimethyl sulfoxide, Acetonitrile, dimethylformamide, diglyme, triglyme, tetraglyme, dimethyl carbonate (DMC), 1,2-diethoxyethane (DEE), diethyl carbonate, dimethylacetamide, and mixtures thereof.

  The above solvents may be used alone or in a mixture. Of the above, preferred solvents are γ-butyrolactone, propylene carbonate, dimethyl sulfite, and 1,2-dimethoxyethane. Of these, the most preferred is a mixture of 1,2-dimethoxyethane / propylene carbonate and γ-butyrolactone.

  Electrolyte salts suitable for use in the application of the present invention are selected from salts that produce an ionic conductive solution in the organic solvent described above. Useful electrolytes include LiBF4, LiAsF6, LiPF6, LiClO4, and Li (SO3 CF3). The only requirement for use is that these salts, whether single or mixed, are compatible with the solvent used and result in a solution with sufficient ionic conductivity. It is to let you. According to the Lewis or electrical concept for acids and bases, many substances that do not contain active hydrogen can function as acceptors for acids or electron pairs. Such a basic concept is shown in the chemical literature (Journal of the Franklin Institute, Vol. 226-July / December, 1938, pp. 293-313, by GN Lewis).

  In order to avoid internal short circuit conditions, the cathode is separated from the Group IA, IIA or IIIB anode material by a suitable separator material. The separator is made of an electrically insulating material, and the separator material does not chemically react with the anode and cathode active materials, and does not chemically react with the electrolyte solution and is insoluble in the electrolyte solution. Furthermore, the separator material has a sufficient porosity to allow the electrolyte to flow during the electrochemical reaction of the battery. Exemplary separator materials include woven fabrics composed of polypropylene and fluoropolymer fibers such as polyvinylidene fluoride, polyethylene tetrafluoroethylene, and polyethylene chlorotrifluoroethylene, which can be used alone or fluorine Polymer microporous film, non-woven glass, polypropylene, polyethylene, glass fiber material, ceramics, polytetrafluoroethylene membrane marketed under the trade name ZITEX (Chemplast Inc.), trade name CELGARD (Celanese Plastic Company, Inc.) And a film sold under the trade name DEXIGLAS (CH Dexter, Div., Dexter Corp.). It is use.

  A preferred separator comprises a non-woven polypropylene fabric or cloth and a laminated polypropylene film or membrane. Preferably, the nonwoven fabric faces the cathode and the polypropylene microporous film faces the anode. Thus, the nonwoven fabric layer functions as a wicking material to wet the cathode more effectively, and serves as a partition for preventing free carbon particles from perforating the polypropylene film.

  A preferred form of the electrochemical cell is a case negative structure in which the anode / cathode couple is inserted into the conductive metal case such that the case is connected to the anode current collector. This case is designed by the special form factor and end use required. Cylindrical, ie C, D and AA battery sizes and prismatic structures are preferred. A preferred material suitable for the case is titanium, but stainless steel, mild steel, nickel, nickel-plated mild steel and aluminum are also suitable. The case header includes a metal lid with a sufficient number of apertures for a glass-to-metal seal / terminal pin feedthrough to fit against the cathode electrode. The anode electrode is preferably connected to the case or the lid. Another opening is provided to fill the electrolyte. The case header includes components that are compatible with other components of the electrochemical cell and is resistant to corrosion. Thereafter, the battery is filled with the above-described electrolyte solution and sealed in a sealed state by, for example, closing welding a stainless steel plug covering the filling hole, but is not limited thereto. The battery of the present invention can also be configured with a case having a positive electrode structure.

  The novel cathode composition of the present invention is particularly useful in biomedical devices because it does not swell during discharge. This novel composition has higher specific capacity and higher discharge rate capability than commonly used industrial products based on fluorinated petroleum coke or similar materials. In addition, cathodes made with this composition can be used during discharge as compared to cathodes made with commonly used fluorinated carbon, or cathodes made with only fluorinated carbon fibers. (No increase in cathode volume).

  The present invention further provides a biomedical device powered by the battery of the present invention. For example, cardiac pacemakers and defibrillators known in the prior art can be powered using the battery of the present invention. In addition, insulin pumps, nerve stimulation devices, and any implantable device can be powered using the battery of the present invention.

  Some features and advantages of the present invention will become more apparent from the following examples. However, these samples are intended to illustrate certain preferred states of the present invention in detail, but these are presented primarily for illustrative purposes and the present invention is not limited to these in a broad sense. Is not to be done.

Example 1
Cathode Manufacture Cathodes are made of three types of fluorinated carbon, fluorinated petroleum coke (commonly used in commercial battery manufacturing), fluorinated carbon fiber, and anisotropic carbon of fluorinated viscose rayon fiber. And a mixture of isotropic carbon of 5% by weight fluorinated natural graphite. This fluorinated carbon fiber was produced by fluorination of a carbonized viscose rayon cloth.

  To produce the cathode, 0.3 g of fluorinated carbon, 0.056 g of acetylene black as a conductive additive, and 0.019 g of a fluoropolymer water emulsion as a binder are carefully mixed using the following procedure. did. First, a fluorinated carbon sample (PC / 10, F, or FN) is carefully mixed with acetylene black, then ethyl alcohol is added to the mixture (1 part mixture: 2 parts alcohol) and then the fluoropolymer emulsion is added. Added. The cathode mixture was mixed well and pressed to remove excess liquid. A button-type article was then produced by pressing a controlled amount of this material into a battery case. The button has a diameter of 17 mm and a thickness of 1 mm. This material was dried at 80 ° C. for 1 hour and then dried under vacuum at 350 ° C. for 1 hour.

Battery Manufacture and Testing Test batteries were assembled in a dry argon atmosphere chamber. A total of nine batteries were manufactured for each cathode type. Batteries were made with excess lithium so that lithium metal was used as the anode and this anode was guaranteed not to limit the discharge performance. A lithium metal button (diameter 17 mm, thickness 0.5 mm) was pushed into the battery case. The electrolyte solution, 1M solution of lithium tetrafluoroborate in gamma-butyrolactone, was added to the battery case containing the cathode, and a polypropylene separator was placed on the surface of the cathode. The batteries were then carefully sealed and allowed to equilibrate for several days. Thereafter, these batteries were discharged using a constant load, and the average values for each of the three battery groups are shown below. All discharges were performed until the 2V cutoff was reached.

  From the above data, it is clear that type FN fluorinated carbon (consisting of 95 wt% fluorinated carbon fiber and 5 wt% fluorinated graphite) provides the best performance. Type FN fluorinated carbon provides 15% to 19% greater capacity compared to Type PC / 10 and less than 5% greater capacity than Type F fluorinated carbon.

Example 2
The cathode was made using the method described in US Pat. No. 4,556,618. Fluorinated carbon (either type PC / 10, F or FN) was mixed with carbon black and powdered tetrafluoroethylene resin in a ratio of 10: 2: 1 parts, respectively. The three kinds of powders were mixed thoroughly using a mortar and pestle until uniform. Then isopropanol / water solution (70:30) was added to wet the mixture. The wet material was placed in a press mold and compressed, and the disc thus obtained was cut in half and pressed once more in the same mold. The disk thus obtained was placed on an aluminum grid and roll pressed between two mylars. The material was then vacuum dried and cut using a cutting die so that the desired diameter was obtained.

  A battery was assembled using a 2032 coin battery case. The fluorinated carbon cathode was disposed at the bottom of the battery case, and then a separator was disposed so as to cover the cathode. An electrolyte (propylene carbonate-dimethoxyethane containing LiBF4) was added to the separator, and a lithium electrode was placed on the surface. A metal plate was placed on the surface of the lithium electrode, followed by a spring washer to maintain good contact and uniform pressure between the cathode and anode. These cells were designed to be limited cathodes (ie, limited with excess lithium) and assembled in a dry atmosphere chamber.

  The thickness of each cathode was accurately measured before and after discharge. Since the change in cathode diameter is limited by the design of the battery case, only the thickness of the cathode changed during the discharge. The following data shows the volume change measured before and after discharge for cathodes made using three different types of fluorinated carbon. These batteries were discharged at a steady current of 1 mA until a 2 volt cutoff was achieved.

  The data in the table above clearly show that the fluorinated carbon type FN (a mixture of fluorinated carbon fiber and 5 wt% fluorinated natural graphite) does not undergo any change in volume during discharge. In fact, the volume of cathodes manufactured with type FN decreases in volume and increases in density. The spring washer used in the test cell to maintain a constant pressure resulted in a decrease in cathode volume (and an increase in cathode density) observed with a type FN cathode. The other materials, fluorinated fiber (type F) and fluorinated petroleum coke (type PC / 10) both show an increase (swelling) in cathode volume after discharge and a decrease in cathode density.

  It is understood that all equivalent features are intended to be included within the scope of the claimed subject matter of the present invention. The present invention has been described with reference to specific details of certain embodiments thereof, such details not being included within the scope of the appended claims. It is not intended to be considered as limiting the scope of the invention.

Claims (14)

(A) an anode electrode containing an electrochemically active metal as an active material; (b) a non-aqueous liquid electrolyte; and (c) a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon. And a mixture of the fluorinated isotropic carbon and the fluorinated isotropic carbon containing 5 wt% to 30 wt% of the fluorinated isotropic carbon. Energy density battery. The battery according to claim 1, wherein the fluorinated anisotropic carbon is a fluorinated carbon fiber. The battery according to claim 1, wherein the fluorinated isotropic carbon is fluorinated graphite. The battery according to claim 1, wherein the fluorinated anisotropic carbon is a fluorinated carbon fiber produced by fluorination of a viscose rayon polymer. The battery according to claim 1, wherein the fluorinated isotropic carbon is fluorinated natural graphite produced by fluorination of natural graphite. The non-aqueous electrolyte is a group consisting of a lithium salt, a lactone, an alkylene carbonate, a lactam, a polyether, a cyclic ether, a cyclic sulfone, a dialkyl sulfite ester, a monocarboxylic acid ester, and an alkyl nitrile. The battery according to claim 1, comprising a solution with a more selected organic solvent. The battery according to claim 6, wherein the organic solvent is γ-butyrolactone. The battery according to claim 6, wherein the organic solvent is a mixture of dimethoxyethane and propylene carbonate. The battery according to claim 6, wherein the organic solvent is dimethyl sulfite. 2. The electrolyte salt according to claim 1, wherein the electrolyte salt is selected from the group consisting of lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium trifluoromethanesulfonate, and a mixture thereof. Battery. The battery according to claim 1, wherein the active metal anode is selected from the group consisting of lithium, potassium, and sodium. The battery according to claim 1, wherein the active metal anode is lithium. (A) an anode electrode containing an electrochemically active metal as an active material; (b) a non-aqueous liquid electrolyte; and (c) a mixture of fluorinated anisotropic carbon and fluorinated isotropic carbon. Power is supplied by a battery comprising a cathode electrode containing as a substance, and the mixture of the fluorinated anisotropic carbon and the fluorinated isotropic carbon contains 5 wt% to 30 wt% of fluorinated isotropic carbon. A biomedical implant device characterized by comprising. 14. The biomedical implantable device according to claim 13, wherein the biomedical implantable device is selected from the group consisting of an implantable cardiac pacemaker, a defibrillator, an insulin pump, and a nerve stimulation device.