CA1234412A - Polymer batteries and fuel cells having protic solvents and methods for their construction and use - Google Patents

Abstract

ABSTRACT
Secondary batteries are provided having at least one electrode which comprises a conjugated polymer having conjugated unsaturation along the main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material. The battery is provided with an electrolyte which is protic in nature and which contains at least one ionic dopant capable of doping the polymer to a conductive state in the electrolyte. Methods of reversibly doping certain conjugated polymers in protic media are also disclosed. Fuel cells and electrolytic cells are also provided employing the protic doping systems and cells disclosed.

Description

POLYMER BATTERIES AND FUEL CELLS HAVING_PROTIC SOLVENTS
AND MET~ODfi FOR THEIR CONSTRUCTION END USE

Certain aspects of the invention described herein were made during the course of York performed under grants or awards from the Office of Naval Research and from the Defense Advanced Research Project Agency through a grant monitored by the Office of Naval Research.

FIELD OF THE INVENTION
This invention relates to electr~chemical doping procedures or the selective modification of the electrical conductivity properties of certain conjugated polymers, and to the application of such procedures to the design of novel, lightweight, high energy density and high power density secondary (reversible) batteries. This invention is also directed to fuel cells wherein simultaneous electrochemical reduction of electrochemically reducible species and electrochemical oxidation of electrochemically oxidizable species takes place at different electrodes, with concomitant generation of electric current together with methods for such generation. Reverse reactions, electrolysis, are also contemplated hereby All of the foregoing embodiments of this invention employ conjugated polymers having conjugated unsaturation along a main backbone chain thereof as either or both of anodic and cathodic means in electrolytic cells, batteries and/or fuel cells. Electrolytes are also employed in connection with the embodiments of this invention, which electrolytes comprise solvents which are erotic in nature, that is, which are able to donate protons readily. Examples of such solvents include water, alcohols, amine, and other solvents well known to those skilled in the art.

BACKGROUND OF THE INVENTION
It has recently been found that acetylene polymers, such as polyacetylene, can be chemically doped in a controlled manner I

with electron acceptor and/or electron donor do pants to produce a whole family of p-type and n-type electrically conducting doped acetylene polymers whose room temperature electrical conductivity may be preselected over the entire range characteristic of semi-conductor behavior and into the range characteristic of metallic behavior. Such doping procedures and the resulting doped acetylene polymers are described and claimed in the commonly assigned U.S. Patent No. 4,222,903, of Alan J. Hedger, Alan J.
MacDiarmid, Cowan K. Shying, and Haddock Cherokee, issued September 16, 1980; and in the commonly assigned U.S. Patent No. 4,204,216, of Alan J. Hedger, Alan G. MacDiarmid, Cowan K.
Shying, and Shucking Gaul issued May 20~ 1980. As described in said Fleeter, et at. patents, a p-type material is obtained with electron acceptor do pants, and an n-type material is obtained with electron donor do pants. The resulting room temperature elect tribal conductivity of the doped acetylene polymer increases with increasing degree of doping up to a certain point where the maxim mum conductivity is obtained or any given Dupont. Such maximum conductivity generally is obtained at a degree ox doping not greater than about 0.30 mole of Dupont per -OH- unit of polyp acetylene.
The doping procedures described in said edgier, et at.
patents involve merely contacting the acetylene polymer with the Dupont, which may be either in the vapor phase or in an aprotic solvent; uptake of the Dupont into the acetylene polymer occurs by chemical reaction and/or charge transfer to a degree proper-tonal with both the Dupont concentration and the contacting period. The concentration and contacting period can be co-ordinate and controlled so that the corresponding degree of doping will be such as to provide the resulting doped acetylene polymer with a preselected room temperature conductivity.
Doped acetylene polymers together with other polymers having conjugated unsaturation in a backbone chain thereof con-statute one class of recently developed molecular solids exhibiting relatively high levels ox electrical conductivity.

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Several other molecular solids have previously been investigated as electrode materials in attempts at improved battery design. For example, U. S. Patent Jo. 3,660,163 issued May 2, 1972 to Moser; and Schneider, et Allah Pro. Into Power sources Con., 651-659 (1974), describe the use of a charge transfer complex of poly-2-vinylpyridine with excess iodine as a cathode material in a solid-state lithium-iodide primary battery employing lithium iodide as a solid electrolyte.
A recent article by Yoshimura, appearing in Molecular Metals, William E. Hatfield, Ed., NOAH Conference Series, Series VI: Materials Science, pp. 471-489 (197~), at pages ~74-476, refers to the above described prior art solid-state lithium-iodine primary battery constructed with poly-2-vinylpyridine-iodine charge transfer complex cathode materials, and broadly speculates that a number of the molecular metals, including doped polyacetylene, might possibly find similar utility as cathode materials in battery design.
No details are provided in regard to the possible construction or mode of operation of such hypothetical batteries, however.
Furthermore, the possibility of doped acetylene or other conjugated polymers being employed as anode materials or as one or both of the electrode materials in a secondary battery construction, i.e., in batteries which are capable of being charged and discharged over many cycles, is not suggested in this article.
In the aforementioned Moser US S. Patent No. 3,660,163, a number of organic donor components in addition to polyvinylpyridine are listed as being suitable for forming the iodine charge transfer complex cathode material. The only one of these many materials listed in the patent which happens to be a conjugated polymer is polypyrrole. Moser attaches no particular significance to polypyrrole, either as being a conjugated polymer or as having any unique electrochemical properties in either its uncompleted or iodine-complexed form, which might set it apart from the many other organic donor components listed therein. There is no appreciation in the Moser patent that doped polypyrrole, or any other doped ~;23~

conjugated polymer, could be used as one or both of the electrode materials in a secondary battery construction.
Polymers such as polyacetylene and polyphenylenes have been disclosed to be reversibly, electrochemically dupable by a variety of Dupont species in aprotic solvents. Further, second defy, reversible batteries are also disclosed as being able to be constructed from such materials. Secondary batteries are disk closed as being constructed from conjugated polymers having coinage-grated unsaturation along a main backbone chain thereof, said polymer being electrochemically reducible to an n-type doped material and electrochemically oxidizable to a type doped material in non-aqueous electrolytes comprising a compound which is ionizable into one or more anionic or cat ionic Dupont species capable of doping the polymer to one of the oxidized or reduced states.
British Patent 1,216,549 - Josefowicz, together with French Patent 1,519,729, Jozefowicz, and "Conductivity of High Polymer Compounds in Solid State", Josefowicz, East Ion Transport in Solids - Solid State batteries and Devices, Proceedings of a NATO sponsored Advanced Study Institute, Belgirate, Italy, pp. 623-63S (1973) r discloses the electrochemical doping of certain polymers, especially polyaniline, in erotic media, however the polymers disclosed are not electrochemically dupable to both p and n states.
None of the foregoing are believed to anticipate or render obvious, either alone or in combination, this novel invent lion as reflected by the claims.

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Jo SUMMARY OF THE INVENTION
-It is an object of this invention to provide secondary batteries having one or more electrodes comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material, and an electrolyte comprising a erotic solvent together with at least one ionic Dupont capable of doping the polymer to a conductive state in the electrolyte.
Another object is to provide secondary batteries having aqueous, alcoholic, or ammonia Cal electrolytes.
A further object is to provide secondary batteries comprising polyacetylene or polyphenylene electrode materials and erotic electrolytes.
Another object is to provide chemical methods for doping certain conjugated polymers.
Secondary batteries wherein erotic solvent-based electrolytes are employed which are capable of doping conjugated polymers comprising one or more electrodes of the battery to a conductive state are also contemplated hereby.
Electrochemical methods for modifying the electrical conductivity of organic polymers are also principal objects of this invention.
It is a further object to provide methods for reversibly doping certain conjugated polymers in erotic solvents, especially aqueous solvents.
It is yet another object of the present invention to provide electrochemical fuel cells capable of simultaneously oxidizing an oxidizable species and reducing a reducible species at different electrodes with the concomitant generation of electric current.
Another object of this invention is to provide electrochemical fuel cells employing certain conjugated polymers which are dupable with Dupont species to a conducting state for the catalytic oxidation-reduction of suitable oxidizable and reducible species.

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Yet another object of this invention is to provide methods for the electrochemi~cal generation of electric current through the conjugated polymer-catalyzed oxidation-reduction of suitable oxidizable and reducible species in erotic, especially aqueous, media.
A further object of the invention provides electrolysis of chemical species into their constituent elements or compounds by the application of current to suitable electrochemical cells employing conjugated polymers as catalyst electrodes.
Yet another object is to provide methods for electrode-fining of metals.
Further objects will be apparent to those of ordinary skill in the art from a review of the present specification, to-getter with those materials referenced above.
The foregoing objects and other objects are achieved through the employment of certain conjugated polymers in erotic electrolytic media. Similarly, certain electrochemical doping pro-seeders are employed in order to facilitate attainment of the fore-going objects. Secondary batteries may be produced having good reversibility, life times, power densities, energy densities, and overall coulombic efficiency comprising an anode, a cathode, and an electrolyte. One or both of the anode and cathode comprises a con-jugated polymer having conjugated unsaturation along a main back-bone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material. The electrolyte comprises a erotic solvent and at least one ionic Dupont capable of doping the polymer -to a conductive state in the electrolyte. The foregoing secondary -pa- 3189-271 battery may be "charged" by passing current through the cell to effect doping of the conjugate polymer to a more highly conducting state in a reversible fashion. Reversing this process -discharge-provides electric current and returns the polymer to a less highly doped state.
In accordance with the present invention, an electron chemical fuel cell may-be provided comprising an I

electrolyte, electrochemically oxidizable fuel, an electrochemically reducible oxidizing agent and catalyst electrode means in contact with the electrolyte comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material. The electrolyte comprises a erotic solvent, and at least one ionic Dupont capable of doping the polymer to a conducting state in the electrode.
Second electrode means in contact with the electrolyte is also provided for current collection and other purposes. The foregoing electrochemical fuel cell may be employed for the electrochemical generation of electric current by withdrawing current from the fuel cell to effect at least a partial electron chemical oxidation of the fuel and at least a partial electrochemical reduction of the oxidizing agent. The foregoing fuel cell may likely also be operated in "reverse' as an electrolysis cell. Thus, an electrical over-potential may be applied to the catalyst and second electrodes of the electrochemical fuel cell as described to cause electrolysis of the oxidized and reduced materials back into their oxidizable and reducible forms. In accordance with a preferred embodiment one or both of the fuel and oxidizing agents is a gas.
An aspect of the present invention provides an electrochemical cell comprising first and second electrodes, at least one of said electrodes comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxizable to a p-type doped material and electrochemically reducible to an n-type doped material, and an electrolyte, said electrolyte comprising a erotic solvent and at least one ionic Dupont capable of doping said polymer to a conductive state in said electrolyte.

- pa -One embodiment of the first aspect of the invention provides a secondary battery comprising an anode; a cathode comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereon, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material; and an electrolyte, said electrolyte comprising a erotic solvent and at least one ionic Dupont capable of doping said polymer to a conductive state in said electrolyte.
Another embodiment of the first aspect of the invention provides a secondary battery comprising a cathode; an anode comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemicaLly reducible to an n-type doped material; and an electrolyte, said electrolyte comprising a erotic solvent and at least one ionic Dupont capable of doping said polymer to a conductive state in said electrolyte.
Still another embodiment of the first aspect of the invention provides a secondary battery comprising an anode; a cathode; and an electrolyte; said anode and cathode each comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electron chemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material; said electrolyte comprising a erotic solvent and at least one Dupont capable of doping said polymer to a conductive state in said electrolyte; the cathode polymer being electrochemically p-doped with said Dupont to an oxidized state as compared with the anode polymer.
A further embodiment of the first aspect of the invention provides an electrochemical fuel cell comprising: an electrochemically oxidizable fuel;
cm electrochemically reducible oxidizing agent; catalyst electrode means I

- 7b -comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material; an electrolyte in contact with said catalyst electrode comprising a erotic solvent, and at least one ionic Dupont capable of doping said polymer to a conductive state in the electrolyte; and second electrode means in contact with the electrolyte.
The second aspect of the invention provides an electrochemical method for modifying the electrical conductivity of an organic polymer comprising providing an electrochemical cell comprising an anode; a cathode, at least one of said electrodes comprising a conjugated polymer having conjugated maturation along a main backbone chain thereof, said polymer being el.ectrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material; and an electrolyte comprising a erotic solvent and at least one ironic Dupont capable of doping the polymer to a conductive state in said electrolyte; and passing current through the cell -to effect said doping of the polymer to a more highly conducting state, said doping being substantially reversible.
The third aspect of the invention provides a method for the electron chemical generation of electric current comprising providing an electrochemicalcell comprising an electrochemically oxidizable fuel; an electrochemically reducible oxidizing agent; an electrolyte; catalyst electrode means in contact with the electrolyte comprising a conjugated polymer having conjugated unsatu:ration along a main backbone chain Thor, said polymer being electron chemically oxidizable to a p-type doped material and electrochemically reducible to all n-type doped material; said electrolyte comprising a erotic solvent, and I

- 7c -an ionic Dupont capable of doping said polymer to a conducting state in the electrolyte; and second electrode means in contact with the electrolyte; and operating the cell to effect at least a partial electrochemical oxidation of said fuel and at least a partial electrochemical reduction of said oxidizing agent .
BRIE DESCRIPTION OF TIRE DRAWINGS
Figures 1 through 4 depict the spontaneous chemical doping of polyacetylene in aqueous acid solutions in accordance with certain of the Examples.

DESCRIPTION OF CERTAIN PREFERRED EMBODIMENTS
As used herein, the term "Dupont" or "ionic Dupont" for a polymer refers to an ionic species which is capable of associating with the polymer to permit substantial addition or withdrawal of electric charge to/from the polymer and to permit modification of the electrical conductivity owe the polymer. The Dupont, as used herein, therefore may be viewed as an ionic species which provides the counter ionic presence in a polymer I

necessary for the establishment of conductive properties therein. As will be readily appreciated by those skilled in the art, ionic do pants are generally associated with moieties having opposite electrical charge, ire. in compounds, especially as dissociable salts.
In the case of chemical doping of a polymer, the electrical modification of the polymer, i.e. the addition or withdrawal of electrons, is accomplished by contacting the polymer with a chemical species capable of participating in an oxidation-reduction, i.e. redo, reaction with the polymer. In such a case, the redox-participating species may or may not also be the source of Dupont ions for maintaining electrical neutrality in the polymer. In the case where a single chemical species performs both functions, it is possible to confuse the roles. A species which is a Dupont in accordance with the present definition will experience no change in its oxidation state upon doping. A species which participates in a redo reaction will, of course, experience an alteration in oxidization state on account of that participation. Different molecules of the same, original species or, indeed, the same molecules may perform both functions, i.e. serve as redo participant and as Dupont ion The Dupont ion must not, however, react irreversibly with the oxidized or reduced polymer.
As used herein, the phrase "capable of doping" as applied to a Dupont or Dupont ion refers to the ability of the Dupont to associate with the material being doped, e.g. the polymer, to permit the addition or withdrawal of charge and the concomitant modification of conductivity in the material by ensuring electrical neutrality.
As used herein, a "conductive state" as applied to a material such as a polymer, refers to a state of the material in which electrical conductivity as measured in ohm cm is substantially increased over the native state of the material such as, for example, by several orders of magnitude.
Whose skilled in the art will appreciate that a practical definition of "conductive state" may vary depending upon the I

g proposed application of the material under consideration and that it will include both semi conducting and metallic regimes Useful "conductive states" may include states having conductivities above about 10 ohm cm . For common battery uses, conductivities above about 1 ohm tam 1 are most desired.
As used herein with respect to a secondary battery, "anode"
refers to the situp of oxidation and "cathode" refers to the situp of reduction of the battery in the discharging mode, i.e., in the charged battery.
In order to appreciate the unexpected nature of the materials and processes described herein, it is desirable to be familiar with the effects of gaseous oxygen, liquid water, and air on the conductivity of neutral polyacetylene and p doped, i.e. partially oxidized, polyacetylene. The effect of a mixture of the vapors of an oxidizing acid and water on polyacetylene should also ye understood.
Gaseous oxygen will very slightly reversibly oxidize polyacetylene, increasing its conductivity from about 10 ohm tam 1 to about -8 -1 -1 This oxidation is attended by an irreversible chemical reaction, however. The 2 combines chemically with the polyacetylene with concomitant, permanent loss of conductivity after about five minutes of exposure. The conductivity drops to about 10 1 ohm cm after about 17 hours of exposure. See "Kinetics of Doping and Degradation of Polyacetylene by Oxygen", Potion et at., Macromolecules, Vol. 14, pp. 1~0 114 (1981); "Oxygen Doping of Polyacetylene", Potion et at., J.
Polymer Sat., Polymer Letters Ed., Vol. 18, pp. 447-~51 (1980);
"Effects of Oxidation on It Doping of Trans-Polyacetylene as Studied via ESSAYER. and Conductivity Measurements", Potion et at., Polymer, Vol. 23, pp. 439-444 (1982); "Organic Metals and Semiconductors: The Chemistry of Polyacetylene, (SHUCKS, and Its Derivatives", MacDiarmid et at., Synthetic Metals, Vol. 1, pp. 101-118 (1979/80); and "Electrical Transport in Doped Polyacetylene", Park et. at., Journal of Chemical Physics, Vol.
73, pp. 946-957 (1980). The (SHUCKS is destroyed and is I

converted to a complex, unknown mixture of compounds, all of which contain strong adsorption peaks in the infrared spectra characteristic of the carbonyl group, indicating oxidative degradation.
In addition, there are many reports in literature which stress the reduction in conductivity of c1s or trays polyacetylene when exposed to air. See the foregoing references along with "Stability of Polyacetylene Films", Yen et at., Solid State Communications, Vol. I pp. 339-343 (1980); and "A Kinetic Study of the Interactions of Trans-Polyacetylene (SHUCKS with Oxygen", Helm et at., yo-yo, Vol. 23, pp. 1409-1411 (1982).
There have also been many statements in the literature pointing out the reduction in conductivity of p-doped polyacetylene when exposed to air or oxygen. See, for example, "Conductivity and Hall Effect Measurements in Doped Polyacetylene", Seeker et at., Solid State Communications, Vol.
.
I pp. 873-878 (1978); "A Study of Posy (p-Xylylene) - Coated AsF5 - Doped Polyacetylene", Osterholm et at., Journal of Applied Polymer Science, Vol. 27, pp. 931-936 (1982); and "Electrical Transport in Doped Polyacetylene", Park eta Journal of Chemical Physics, Vol. 73, pp. 946-957 (19803.
It has been suggested that p-doped polyacetylene may have at least some chemical stability in certain selected aqueous solutions. As reported in ~igrey, MacDiarmid and Hedger, J.
Comma So., Chum. Comma., p. 594 (1979), (Shucks was electrochemically doped in 0.5M aqueous KIT solution in a few minutes to give (Chit 07)x having a conductivity in the metallic regime The sum of elemental analyses for C, H, and I
was 99.8%. This showed that no reaction with water to incorporate oxygen into the (SHUCKS had taken place. As time proceeded, however, it was believed that the analysis must have been in error, and that oxygen surely must have been incorporated during the doping process. Very recently, however, the experiment was repeated and similar results obtained. Eons the [OH (It Jo 0415]x formed (KIWI%) did not react with water, or, if it did react I

during its electrochemical synthesis, the rate of reaction with water must have been very much less than its rate of formation at least during the time needed for doping Recent studies also show that the rate of decomposition of [Shucks in aqueous solutions of various pi and chloride ion concentration values is slow. See Week et at., A streets, I.V.P.A.C. Thea Macromol. Swamp., July 12-16, 1982, p. 442.
MacDiarmid and Hedger in Comma Surety, Vol. 17, p. 143 (1981) and A. Prong Ph.D. Thesis, University of Pennsylvania, p. ]50 (1980) have found that when a strip of (SHUCKS film anhydrously doped to the metallic regime, having a composition of [CH(AsF5)0 098~x~ was placed in 52% aqueous HO for 15 hours, it was converted, as shown by elemental analysis, to 6)0.026]X Chasm annuluses) No oxygen was incorporated into the material.
As disclosed by MacDiarmid and Hedger in Septic Materials 1, 101 (1979/80), pro tonic acid doping of (SHUCKS by the vapors from strong acids such as HC104 or H2S04 to give doped (Shucks having high metallic conductivities of about 10 ohm tam 1 can be had. For example, when (Shucks film was exposed to the vapor from 70~ aqueous HC104, a material was obtained having a composition by elemental analysis of either [Shekel 127(H2)0-297 x or [Shekel 127(H2)0.2971x according to whether it is assumed that a proton is present or not. Thermoelectric power studies of the HC10~ doped film show the doping is p-type.
The oxygen present in the form of H502 or H20 is therefore zither not combined with the carbons of the OH chain or, if it is combined with those carbons, then it somehow does not impair the conductivity of the material. If the water i combined with the carbons, then this should reduce the pi conjugation and reduce the conductivity of a polyacetylene chain. However, experimentally, the conductivity is increased. If it is not combined with the carbons, this is I

most surprising, since p-doped polyacetylene is a carbonium ion and carbonium ions are known to react instantly with water.
Either of these explanations is most surprising and does not fit in with the present picture of the bonding in p-doped (SHUCKS or with the understanding of the chemical reactivity of carbonium ions heretofore known.
The electrochemical undoing in aqueous solution of conjugated Immures in accordance with the present invention has not been known. Undoing is necessary to have a rechargeable battery or a fuel cell. The attainment of electrochemical doping in aqueous solution does not imply that electrochemical undoing can be performed. In this regard, numerous, irreversible fates for carbonium ions or carbanions generated through the doping reactions could take place and, according to the prior art, would have been expected.
Furthermore, the observation that electrochemical p-doping of polyacetylene in aqueous solution can be performed does not imply that chemical p-doping (or n-doping) in aqueous solution will be possible. Numerous examples of electrochemical oxidations taking place in systems wherein chemical oxidation does not proceed are known. Moreover, the transitory oxygen p-doping of cis-polyacetylene to a maximum conductivity of about 10 ohm tam 1 is inapposite to the present invention. In this regard, the modification of conductivity is attended by proximate, immediate, degradation of the polyacetylene film itself. Only through the employment of do pants in accordance with the present invention is a useful conductivity modification possible in this system.
The polymers which are suitable for use in connection with the present invention are polymers having conjugation along the main backbone chain thereof and which are capable of being electrochemically oxidized to a p-type doped material and electrochemically reduced to a n type doped material. While -the present invention is related to doping in erotic media, identification of the polymers which may be employed in connection with this invention is best accomplished by reference to Us S. Patent 4,321,11~ issued March 23, 19~2~

I: 1 Preferred among the polymers which are suitable for employment in the present invention are the polyacetylenes and polyphenylenes~
Methods for reversible doping of polyacetylenes and other polymers with the present invention, together with methods for the con-struction of secondary batteries, may similarly be had from a review of the foregoing patent and patent application.
The construction of fuel cells in accordance with the present invention, together with the preparation of electrolytic cells for the electrolysis of certain compositions will be apparent to those of ordinary skill in the art from a review of the specification, especially the examples. To provide additional instruction in such construction, the publication Fuel Cells:
Their Electrochemistry, Buckers et all McGraw Hill is mentioned.
The following examples have been prepared more fully to elucidate the present invention. It is believed that those of ordinary skill in the art will have no difficulty in ascertaining what polymers, do pants, media and related materials are suitable for inclusion in the present invention and that the same persons will require but routine experimentation to ascertain useful electrolytic systems for performing the various embodiments of this invention in view thereof It is to be understood that the following examples are offered by way of illustration only and are not to be construed as limiting.

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Use of 48~ Aqueous HBF4 Electrolyte Example 1 Polyacetylene, (SHUCKS, does not react chemically to any significant extent with the non oxidizing acid, HBF4, in its commercial 48~ solution. For example, when a strip of Claus rich (SHUCKS (tam x 0.5cm) was immersed in a degassed solution of 48% aqueous HBF4 for 4 hours and pumped dry for 18 hours, the two-probe conductivity of the film was 6.4 x -4 -1 -1 well below the semiconductor-metal transition.

~2~93~ h Example 2 A series of experiments was carried out in order to determine if p-doped (oxidized) (SHUCKS is stable in 48%
aqueous HBF4. A piece of is rich (SHUCKS (2cm x 4cm) was initially electrochemically doped in 0.5M
(Bu4N)(BF4)/cH2cl2 to about I (measured by the number of coulombs passed). The doped film had a measured two-probe conductivity of 122.5 ohm tam . The film was then cut in half. One half was sent out for chemical analysis and was found to have a composition of [Cal byway FOE 0.100 X
The other half was immersed in degassed 48% aqueous HBF4 for 24 hours, pumped dry for 18 hours, and finally sent out for elemental analysis After immersion and pumping, the film still appeared golden and had a measured two-probe conductivity of 5~.3 ohm lo . The elemental analysis of the aqueous HBF4-immersed sample was 1.08 0.0804 0.214 0.163]x Mote that the boron content increased slightly. Moreover, the hydrogen and oxygen contents (by difference) increase as well.
This can be viewed as an inclusion of HO or the further hydrolysis of BF4 to B 3 or BF2(OH)2 . However, it is important to note that polyacetylene retained its Dupont and remained in the metallic conducting regime.

Lo Example 3 In a second series of experiments, a piece of is rich (SHUCKS (tam x 2cm) was initially electrochemically doped in 0.5M (Bu4~)(BF4)/CH2C12 to about I as before. The doped film was then cut in half. The first tam piece of [CH~Y(BF4)y]x and a piece of lead were placed in a degassed solution of O.OlM Pb(BF4)2 in 48~ aqueous HBF4.
The open circuit voltage (VOW) of this cell was 0.810V. The cell was immediately discharged at a constant current of Moe until the discharge voltage of the cell fell to 0.2V
representing the approximate point where hydrogen bubbles off the platinum current collector. 1.231 coulombs were produced corresponding to about 3.9~ discharge. An identical experiment with the other half of the doped material was performed except that the cell was allowed to stand for 18 hours before discharge. The initial open circuit voltage of this cell was 0.818V and the open circuit voltage after 18 hours was 0.6610V. The cell was then discharged at a constant current of Moe until the discharge voltage of the cell fell to 0.2V.
The number of 1.170 coulombs, corresponding to about 3.7%
discharge were produced. Hence, little, if any, Dupont was lost after 18 hours of immersion in 48~ aqueous HBF4. ray the open circuit voltage drops from about 0.82V to about 0.66V
over 18 hours is not known at the present time, although it appears likely that it may be due to diffusion equilibrium of the BY ion between the exterior and interior of the (SHUCKS
fibrils.

Example 4 In a third series of experiments, a lcm2 piece of SHEA Y(BF4)y~x and a piece of Pub were placed in O.OlM
Pb(BF4)2 in 48% aqueous EIBF4. As in Examples 2 and 3, the initial open circuit voltage of this cell is typically about 0.8V and the short circuit current (Is) is typically about Moe. This cell was successfully cycled two times (discharge/charge) at a constant current of Moe to/from a discharge voltage of about 0.2V. It appears that doped (oxidized) (Shucks can be electrochemically reduced, electrochemically deoxidized and electrochemically reduced again in 48% aqueous BF4. The coulombic efficiency of the second and third steps above was about 53%. After two complete cycles (discharge/charge) the open circuit voltage was OVA
and the short circuit current was Moe. Little, if any decomposition of the (SHUCKS was visually observed upon this cycling of the system. Attempts to oxidize neutral (SHUCKS to the metallic regime in 48~ aqueous HBF4 were unsuccessful.
However, films of polyacetylene, (SHUCKS can be reversibly oxidized and reduced in aqueous solutions of the non-oxidizing acid HBF4 if the (Shucks is first "activated" by aprotically p-doping it with BF4 in (Bu4~)(BF4)/CH2C12 solution. From the foregoing, batteries can be constructed utilizing either p-doped (oxidized) (Sioux or "activated"
(Shucks, i.e., (SHUCKS which has been electrochemically oxidized in an aprotic solvent and electrochemically reduced in 48% aqueous HBF4.

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Stabilization of p-doped (SHUCKS in the Metallic Regime to Air It has previously been believed that oxygen (in air destroys electrical conductivity of p- and n-doped polyacetylene~ It has now been found that 2 can actually be used to increase the conductivity of (Shucks to the metallic regime by p-doping and that (Shucks may be stabilized towards oxygen in its highly conducting metallic, p-doped state by treating it with certain acids.

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Example 5 The first series of experiments was carried out in order to determine if SHEA) could be chemically oxidized by

2 with the incorporation of a suitable counter anion. A
strip of Claus rich (SHUCKS film (tam x 0.5cm) was placed in a solution of 48~ aqueous HBF4. Two platinum clips wore attached to each end of the (SHUCKS film. Oxygen gas was bubbled over the (SHUCKS film and the resistance of the film monitored as a function of time. The resistance dropped rapidly at first but leveled off after about 4-6 hours. The film was dried in vacua and its two-probe conductivity measured. In several identical experiments, the p-doped (oxidized) material had a two-probe conductivity between about 0.1 ohm tam 1 and 1 ohm tam 1.

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Example 6 In a similar experiment, a strip of Ox film (leukemia x 0.5cm) was wetted with 48% aqueous HBF4 and allowed to stand in 2 gas at about 700 torn. Again, the resistance dropped rapidly at first but leveled off after about 18 hours.
The film was pumped dry and its two probe conductivity measured. In several identical experiments, the p-doped oxidized material had a two-probe conductivity between 0.1 ohm tam 1 and 1 ohm cm I

Example 7 It was confirmed that 2 acts as the oxidizing agent in Examples 5 and 6. Two pieces of Claus rich (CHjX (tam x 0.5cm) were mounted in two four-probe conductivity apparatuses. Each piece of film was wetted with 48~ aqueous HBF4 for 30 minutes and separately evacuated. 2 gas, about 700 torn, was introduced to one while I gas, about 700 torn, was introduced to the other. The resistance of the samples was monitored as a function of time. After 5 days the four probe conductivity of the material in the oxygen atmosphere was about 0.83 ohm cm , while the four probe conductivity of the material in the nitrogen atmosphere was 1.47 x 10 ohm cm . The conductivity exhibited by the latter film is believed to be due to the ionic conductivity of the aqueous HBF4 wetting the film and/or to the presence of traces of 2 in the I gas.

I

Example 8 A second series of experiments was carried out in order to determine whether (SHUCKS can be stabilized towards oxygen in its highly conductive, metallic, p-doped state.
(SHUCKS was doped in 0~5M (BU4~)(BF4~/ 2 12 to about 6% as in Example 2. The film was then cut in half and each 2cm x 0.5cm piece was mounted to a four-probe conductivity apparatus. One piece was wetted with 48~ aqueous HBF4 while the other was loft dry. Both pieces were exposed to the air and the resistance of the samples monitored as a function of time. The data are reported in Table I. It is apparent that 2 is capable of oxidizing (SHUCKS to the metallic regime and that this oxidization can be stabilized with certain acids such as aqueous HBF4.
Table I
Wetted Unwetted Time (hr.) (ohm-lcm-l) (ohm-1cm-1 0 1.36 x 102 2.50 x 102 168 2.05 x 101 1.4g x 10 336 1.70 x 101 3.54 x 10 1 504 6.1~ x 10 7.36 x 10 2 672 1.25 x 10 1.93 x 10 2 ~23~

Material from Examples 5-8 - rationale These results stem from our recent discoveries based in part on the two redo equations listed below:
(SHUCKS (OH Yucca E (vs. NAVAHO
2H2 OWE eye E (vs. NAVAHO
Net reaction:
4(CH)x~xyO2~4xyHBF~ SHEA Y(BF~)y~x+2XyH20 THE refers to the Standard Hydrogen Electrode.
The value of fox varies according to the value of "y". When "y" is infinitesimally small, i.e.
when one is measuring "parent unhoped (SHUCKS, fox is about ~0.6V (vs. NO using the convention that H eye has an E ox=+3.05V
vs. THE). The value of fox becomes more negative as the value of "y" increases. For example, when yo-yo then EoX=0.63V vs. THE.
From our discoveries it becomes apparent that, thermodynamically, oxygen will want to oxidize (SHUCKS to (OH Yucca If only oxygen and water are present then the counter anion for the (OH Yucca species must be something such as OH , -1 ' or -2 Such oxygenated species will combine with (SHUCKS and destroy it, giving either C-OH and/or COO bonds. If, however, another counter anion other than the oxygen containing species is present, e.g., the BF4 ion, then the BF4 ion will combine with the (OH Yucca to give a species such as [OH Y(BF4)y]x which will be stable in the presence of oxygen and water once it has obtained its fully oxidized state in the presence of oxygen. It is not necessary to use free acid. Solutions of other aqueous acids such as HPF6, HC104 may be used instead of HBF4.
The above stabilizations refer to stabilization in acidic medial however stabilization may also be brought about in neutral or basic media as given by the redo reaction below.
40H Owe (lMbase) Eox(vs. NAVAHO

OX

- I -Use of (OH) as a Fuel Cell Electrode Polyacetylene, Ox can be used as a fuel cell electrode. We have discovered that p-doped (oxidized) (SHUCKS can act as an oxidizing agent whereas neutral (SHUCKS, either "as synthesized" or previously "activated", can act as a reducing agent for a variety of organic and inorganic compounds in erotic media, especially aqueous media.

sample 9 It was found that neutral "as formed" Claus rich SHUCKS either did not react electrochemically or reacted to produce small currents. If, however, it was first "activated" as disclosed below, its electrochemical characteristics as an electrode nearly always were extremely improved. The exact nature of the activation process and/or mechanism is not yet known.
A series of experiments were carried out in order to determine if "activated" (SHUCKS could act as a reducing agent. "Activated" (SHUCKS was prepared as follows: a tam piece of [OH Y(BF4)y]x synthesized as in Example 2, and a piece of lead were placed in a solution of I aqueous HBF4. A Pi clip was previously attached to the top of the [OH Y(BF4)y]x and the Pi clip was covered with paraffin wax in order to isolate the Pi from the solution. The electrodes were about loom apart in a "U-cell" type configuration divided into two compartments by a glass Fritz The open circuit voltage (Vow) of this cell was about 0.68V. The doped film was then discharged at a constant potential of OVA versus lead. The current dropped from 18.OmA to Moe in about one hour to give a final Vow of about 0.2V, characteristic of almost completely "unhoped", i.e. neutral (OH) .
2 gas was then bubbled over the strip of activated (SHUCKS. The current immediately rose to about Moe and remained at that level for 2 hours. The :~23'~

experiment was then arbitrarily terminated The number of coulombs passed was 4.83 C, corresponding to the passage of 0.181 electrons per OH unit in the (Shucks A
significant current flowed only when 2 was passed over the (SHUCKS electrode. When the 2 gas was stopped, the current immediately dropped from about Moe, leveling off at about Moe after about 1 hour. It is apparent that (SHUCKS is acting as a "catalyst" or a "fuel cell electrode", the fuel being lead in this case and the 2 acting as oxidizing agent. The 2 oxidizes the (SHUCKS
chemically to [OH Y(BF4)y]x which is then immediately reduced electrochemically by the lead. The composition of the (SHUCKS is believed to remain essentially unchanged during the reaction. The net reaction is believed to be:
2Pb+02+4HBF4 2Pb(BF4)2~2H20 Example 10 A lcm2 piece of is rich (OH) "activated" in x accordance with Example 9 was allowed to discharge at a constant potential of OVA versus lead for 24 hours while 2 was constantly bubbled over it. The average discharge current for the 24 hr. period was Moe and the total number of coulombs produced was 58.35C, corresponding to the transfer of 2.187 electrons per OH unit in the (SHUCKS. This experiment was repeated with a tam piece of is rich (OH) "activated" in accordance with Example 9. Instead of using a Pi wire clip as the current collector, a thin carbon sheet was connected to the (SHUCKS using electrodag. The cell was allowed to discharge at a constant potential of OVA versus lead for 24 hours Chile 2 was constantly bubbled over it.
The average discharge current for the 24 hour period was Moe and the iota' number of coulombs produced was 30.729C, corresponding to the transfer of 0.9113 elections per OH unit in the (Shucks.

Example 11 2 A tam piece of [CH~y(BF4)y]X activated in accordance with Example 9 and a carbon rod were placed in a solution of 48~ aqueous HBF4 in a "U-cell" type configuration divided into two compartments by a glass Fritz A Pi clip was previously attached to the top of the [OH ~(BF4~y]X and the Pi clip was covered with paraffin wax in order to isolate the Pi from the solution. A 50/50 Volvo hydrazine/water mixture was added to the carbon rod compartment. The open circuit voltage (VOW) of this cell was about 0.84V. The doped film was then discharged at a constant potential of 0.000~ between the two electrodes. The current dropped from Moe to O.lOOmA in 30 minutes. 2 gas was then bubbled over the strip of activated (SHUCKS. The current immediately rose to about Moe and slowly dropped to Moe in 2 hours.
Bubbles of No gas were observed forming on the carbon rod.
The number of coulombs passed was 2.469C, corresponding to the passage of 0.0694 electrons per OH unit in the (SHUCKS. The 2 oxidized the (SHUCKS chemically to [OH Y(BF4)y]x which is then immediately reduced by electrons liberated by the reduction of the N2H4 at the C rod, which are transferred to the SHEA Y(BF4)y~x via the external wire. The composition of the [OH Y(BF4)y~x is believed to remain unchanged during the reaction. The net reaction is thought to be:
N2H4+02 N2+2~12 The reduction in the current during the two hour experiment is believed to be due to the 50/50 NOAH mixture being alkaline. this mixture slowly neutralizes the acidic media in which the (SHUCKS electrode is immersed.

I

Example 12 A 1.5cm x 2cm piece of c1s rich (SHUCKS film and a strip of Pub wire were immersed in an 0.5M Pb(C104)2 solution in 12 M HC104. The electrodes were about loom apart. After equilibrium for four hours the (SHUCKS exhibited an Eon (vs. Pub) of 0.85V indicating chemical doping of the (SHUCKS. The two electrodes were connected via an ammeter and a (very large) short circuit current of Moe was observed.
The short circuit discharge was continued for 18.5 hours after which the short circuit current had dropped to lima. A white precipitate of PbC12 coated the polyacetylene film and was present at the bottom of the cell. The 1077 coulombs which had passed during this time corresponded to 14.4~ positive charges being placed on each (OH) unit, i.e. to 1445% doping of the (SHUCKS, if the charges had remained on the (SHUCKS. The results of this experiment can be explained in the following manner. Upon connecting the chemically oxidized (OH) electrode, i.e. [OH Y(C104)y]x, and the lead electrode, the (SHUCKS electrode is reduced electrochemically by the lead. As soon as the (Shucks is even slightly reduced, the acid immediately chemically oxidizes it back to [OH Y(C104)~]x This series of electrochemical reductions and chemical oxidations can go on continually until it is mechanically slowed down by the deposition of insoluble PbC12 on the surface of the (SHUCKS film. The net reaction is believed to be 8Pb~16HC104 7Pb(C104)2+PbC12~8H20 ~23~

Example 13 Example 12 was repeated with a tam x 2cm piece of is rich (SHUCKS film. The cell had an initial short circuit current of Moe and ran a small electric motor in excess of 6 hours. The surface of the film was then coated with a PbC12 precipitate. The film was washed briefly in water to dissolve some of the PbC12 and replaced in the cell. An Eon (vs.
Pub) of 0.82V was obtained after 5 minutes and a short circuit current of Moe was then observed. The motor could then again be run by the cell.

1;~3~

Example 14 A tam piece o-f is rich (SHUCKS film attached by a Pi wire clip at the top and a carbon rod were immersed in a 12M
HCl04 solution. The electrodes were about loom apart in a "U-cell" type configuration divided into two compartment by a glass Fritz A 50/50 Volvo hydrazine/water mixture was added to the carbon rod compartment. After equilibrium for 30mm, the open circuit voltage (V0c) was 0.814V. The cell was allowed to discharge at a constant potential of OVA. An initial short circuit current of Moe was observed. The short circuit discharge was continued for 2 hours after which the short circuit current had dropped to Moe. Bumbles of No gas were observed on the carbon rod. About 11.43C had passed during this time corresponding to the passage of 0.257 electrons for each OH unit in the (OH) .
The reduction in the current during the two hour experiment is believed to be due to the fact that the 50/50 N2H4/H20 mixture is alkaline and that this then reacted in the pores of the glass fruit to precipitate insoluble (~2H5) +(C104) in the pores of the Fritz Such a clogging of the fruit would impair free movement of ions through the fruit and hence reduce the current.

~;23~

Example 15 A cell similar to that of Example 9 was prepared having an open circuit voltage (Vow) of 0.778 V. The doped film was then discharged at a constant potential of OVA us Pub. The current dropped from Moe to Moe over 30 minutes Benzoquinone was then added to the "activated"
(OH) compartment; the current immediately rose to about Moe, slowly dropping to about Moe after 2 hours. The number of coulombs produced was 37.117C corresponding to the passage of 1.391 electrons per OH unit. The (SHUCKS acted as a "catalyst", i.e. as a "fuel cell electrode", the fuel being lead and the oxidizing agent being benzoquinone. The benzoquinone oxidized the (OH) chemically to [OH Y(BF4)y]x which was then immediately reduced electrochemically my the lead. Hydroquinone and lead floroborate were produced overall. The composition of the (SHUCKS appeared to remain unchanged during the reaction. The overall reaction may be represented by the following equation 0= =0~2HBF4~Pb HO- -OH+Pb(BF4)2 The reduction in the current during this two hour experiment is believed to be due to the fact that insoluble hydroquinone is deposited on the surface of the (SHUCKS film.

Example 16 A piece of Claus rich SHUCKS (tam x 2cm) was initially doped in 0.5M (Bu4N)(BF4)/CH2C12 to about 6% as in Example 2. The doped film was then cut in half and the two places of [OH Y(BF4)y]x were placed in a solution of 48~ aqueous HBF4 about loom apart in a "U-cell" type configuration which was divided into two compartments by a glass Fritz The open circuit voltage of this cell was, of course, OVA. Benzoquinone was added to one compartment and Crook was dissolved in the other. The open circuit voltage immediately rose to about lo and stabilized at 1.123V after about 30 minutes. The film immersed in the benzoquinone/48%
aqueous HBF~ solution was oxidized to a higher oxidization level while the film immersed in the Crook aqueous HBF4 was believed to be reduced to neutral (Shucks since the film lost its golden color, characteristic of oxidized film. The cell was discharged at a constant potential of OVA, oxidizing Or 2 to Or 3 while reducing the benzoquinone. The initial short circuit current was Moe which fell to Moe after about 4 hours. A total of 17.257 coulombs were produced. This corresponds to the passage of 0.495 electrons per OH unit. The overall reaction may be represented by the following equation cry OH HO -Okra I

Example 17 An analogous experiment to Example 16 was performed where Crook was replaced with hydrazine. Benzoquinone was added to one compartment of the "U" cell and a 50/50 Volvo hydrazine/water mixture was added to the other. The pi of the hydrazine/water mixer was still less than 0. The film immersed in the benzoquinone/48% aqueous ~F4 solution was spontaneously chemically oxidized to a higher oxidization level while the film immersed in the hydrazine/48~ aqueous ~BF4 was spontaneously chemically reduced and some bubbles appeared on its surface. The cell was discharged at a constant potential ox OVA. The initial short circuit current was Lomb and Poll to Moe after 2 hours. About 3.556 coulombs were produced corresponding to the passage of 0.128 electrons per OH
unit.

1~3~

Example 18 An analogous experiment to Example 17 may be performed where benzoquinone is replaced with oxygen. Oxygen gas would be bubbled in one compartment of the "Swahili" and a 50/50 Volvo hydrazine/water mixture added to the other. The hydrazine/water mixture would be acidic. The film over which oxygen is bubbled in 48% HBF4 would be spontaneously, chemically oxidized to a higher oxidation level while the film immersed in the hydrazine/48~ aqueous HBF4 would be spontaneously, chemically reduced and some bubbles would appear on its surface indicating progress of the reaction.
While final evaluation of Example 17 has not yet been made, the results for that example as well as for example 16 and those expected for Example 18 demonstrate that [OH Y(BF4)y]x can act as a good oxidizing agent. Both cry and H2NNH2 were believed to be oxidized by [OH Y(BF4)y]x to Cry and No respectively. In conclusion, it is apparent that (Shucks (especially when activated) either or [OH Yucca can act as an electrode in fuel cell type processes in erotic media either for the reduction or oxidation of a variety of organic and inorganic chemical species.

Lo Chemical p-doping of (SHUCKS in aqueous solution Example 19 A piece of Claus rich (SHUCKS film (1.4cm x .4cm) was attached to two platinum clips and immersed in an aqueous solution of H2S04. The resistance of the film was monitored versus time. Identical experiments were carried out with degassed EM, EM 12M, 15M, and 18M aqueous H2S04 solutions. Both the log vs. time for each specified concentration as well as the after 30 minutes versus polarity were plotted in Figures 1 and 2 respectively. It can be seen that (SHUCKS undergoes a semiconductor-metal transition in aqueous solution The conductivity at first slowly increases from 10 ohm cm and then suddenly increased from about 4 h -1 -1 to 140 ohm~lcm-l as the acid concentration was increased from 12M to 18M. When the resulting flexible golden film was removed from the 18M
solution and was washed with cyclohexene (to remove H2S0~) the film still had a conductivity of about 100 ohm tam The reaction occurring is believed to be represented by the following equation 2(CH)x~3xyH2SO4 SHEA Y(HS04)y~x~~XyH2S03+XyH20 It is possible that the H2S03 may, itself, also be reduced further.

I

Example 20 In an experiment similar to Example 19, a piece of Claus rich (SHUCKS film (1.4cm x 0.4cm) was attached to two platinum clips and immersed in an aqueous solution of HC104. The resistance of the film was monitored us time. Identical experiments were carried out with degassed EM, EM, EM and 12M
aqueous HC104 solution. Both the log versus time for each specified concentration as well as the after 30 minutes versus polarity were plotted and are shown in Figures 3 and 4 respectively. The (Shucks undergoes a semiconductor-metal transition in aqueous HC104 solution. Note that the conductivity increased from about 5xlO ohm cm to about 5 ohm tam 1 and finally to about 350 ohm tam 1 as the acid concentration was changed from EM to 12M. The reaction occurring is believed to be represented by the following equation SHEA) +9xyHC104 SHEA Y(C104)y]x+xyHC1+xyH20 The studies of Examples 19 and 20 demonstrate that strong, aqueous H2S04 and HC104 can chemically p-dope (SHEA film immersed therein. The reaction occurring when (SHUCKS is immersed in strong H2S04 or HC104 is believed to involve the reduction of the acid and the concomitant oxidation of SHUCKS. The conductivity increases with increasing acid concentration. It is believed that as the concentration of acid increases, the (SHUCKS becomes more highly doped since it is know that for (SHEA the conductivity is related to the level of Dupont. From Figures 1-4, it can be concluded that (SHUCKS can undergo a semiconductor-metal transition in acidic aqueous solution.

~L;23~

Electrochemical p-doping of (SHUCKS in Aqueous Solution Example 21 When Claus rich (Shucks film is immersed in 50% aqueous HO for 1 hour and is then pumped in a vacuum system for 18 hours, no experimentally observable increase in weight or conductivity is observed.

I

Example 22 When a piece of c1s rich (SHUCKS film (1.5cm x 2.0cm) is used as the anode and platinum foil as the cathode in 50% HO
and a potential of Levi is applied for a period of 20 minutes, the shucks film becomes doped. After washing in 50~ HO and pumping in a vacuum system for 18 hours a flexible, golden film having a conductivity of about 1 ohm tam 1 was obtained.
Elemental analysis gave a composition corresponding to [Cal 06Fo.og3O.O91]x It is believed that this may have a constitution such as [SHEA (HF2)0 owe 09] .

I

Example 23 A tam piece of Claus rich (SHUCKS film and a piece of lead foil were placed in a saturated solution of PbF2 in 50 aqueous HF. After 30 minutes Eon (vs. Pub) equaled 0.60V.
This implies some chemical doping in the presence of aqueous HF. The (SHUCKS was then attached to the positive terminal of a do power supply and oxidized for 30 minutes at a constant current of Lomb. This corresponds to about I p-doping of the (SHUCKS. The Eon (vs. Pub) 30 minutes after discontinuance of the do current was 0.81V. On connecting the (SHUCKS and Pub electrodes via an ammeter a surprisingly large short circuit current of Moe was observed. It is concluded that the (SHUCKS is electrochemically oxidized upon application of the do current and that this reaction is, at least in part, electrochemically reversible.

I

Example 24 Two pieces of Claus rich (SHUCKS film (tam x 1~5cm) and a piece of platinum foil were placed in a saturated solution of PbF2 in 50% aqueous HF. Fact piece of (SHUCKS in turn was attached to the positive terminal of a do power supply and the platinum attached to the negative terminal. A constant voltage of 1.0V was applied to give about I oxidation of the (SHUCKS. The do power supply was then connected to the two pieces of oxidized (SHUCKS, placed 10mm apart, each having a (assumed) composition of [OH (HF2) o 03]x A
constant voltage of 1.0V was applied for a period so that the same number of coulombs used in the original oxidation of each piece of film had passed. It was assumed that one piece of film now had a composition of [OH ' HO o 06]x~ and the other a composition of (OH) . Upon connecting the two pieces of film via a voltmeter, a potential difference of 0.71V
was observed. On connecting them via an ammeter a relatively large short circuit current of Moe was obtained. These results strongly suggest a reversible electrochemical reaction involving (SHUCKS.

I

Example 25 A piece of is rich (SHUCKS film 2cm x 3cm and a piece of platinum foil were placed in a saturated solution (0.5M) of NaAsF6 in 50~ HF. The (SHUCKS was attached to the positive terminal and the platinum to the negative terminal of a do power supply. A constant potential of Levi was applied between the electrodes for about 30 minutes. The film was then washed in 50% HO and pumped in a vacuum system for 18 hours. In several different experiments flexible, golden, p-doped films having good metallic conductivities of about 10 to 100 hm-lcm-l in the metallic regime were obtained.
Significantly, the films contained no oxygen. The F content varied from one preparation to another, e.g.
[Showoffs 1)0.026]x and [SHOWOFF 7)0.029]x The nature of the Dupont species and the cause of the variable F content is not presently known Example 26 2 A platinum mesh was folded around a tam piece of Claus rich (SHUCKS film and placed loom apart from a piece of lead wire in a saturated solution of PbF2 in 50% HO which was also 0~5M in NaAsF6. The (SHUCKS electrode and the Pub electrode were attached to the positive and negative terminals respectively of a do power supply and a constant current of coma was passed for 30 minutes. This corresponded to an approximately 8.1% oxidation of the (OH) . e ox Pub) of this oxidized, shucks was 0.95V. On connecting the two electrodes via an ammeter a large short circuit current of Moe was observed. In an identical experiment, the (SHUCKS
was found to have an Eon (vs. Pub) of 0.57V after sitting in the electrolyte for 30 minutes prior to any electrochemical studies. Oxidation to 8.1% was carried out as before. Thirty minutes after the oxidation was terminated the oxidized (SHUCKS
exhibited an Eon (vs. Pub) of 0.80V. A short circuit current of Moe was then observed. A reversible, electrochemical reaction appears to occur in the system strongly suggesting its potential usefulness as a storage battery cell.

- I
Example 27 Two 1.0cm x 1.5cm is rich (SHUCKS electrodes attached to a platinum wire current collector were placed in an 0.5M
NaAsF6 solution in 50% HF. A platinum foil electrode was also placed in the solution. Each piece of (SHUCKS film was oxidized separately to about 3% (calculated by the number of coulombs passed) by attaching the film to a positive terminal, respectively of a do power supply. The electrochemical oxidation of the (Shucks was carried out at a constant applied potential of 1.0V. The two pieces of (SUE 10mm apart in the electrolyte were then attached to the positive and negative terminals of a do power supply at a constant applied potential of 1.0V. The number of coulombs passed were such that one piece of oxidized (SHUCKS was reduced to neutral (SHUCKS and the other further oxidized to about I The open circuit voltage then observed between the two pieces of film was 0.68V. On connecting the two pieces of film, a short circuit current of Moe was observed. After a 30 minute short circuit discharge, the current had fallen to 0O01mA
representing a 17% coulombic efficiency. Accordingly, this system has potential as a rechargeable storage battery cell.

I

Example 28 In several separate experiments using a saturated solution of NaPF6 in 50% HO as an electrolyte, 1.5cm x 2.Ocm pieces of (SHUCKS film were attached to the positive terminal and a piece of platinum foil was attached to the negative terminal of a constant potential (1.25V) do power supply for about 30 minutes. The (Shucks was oxidized to about 7.0~ by this process. After washing with 50% HO and pumping for 18 hours in vacua, flexible, golden films having conductivities in the metallic regime, 30 to 70 ohm tam 1, were obtained.
Elemental analyses from two experiments gave compositions corresponding to [CHl.04PO.0081 0.10 0.13]x and [Cal llPO.0071FOol4 0.05 x oxygen (by difference) is apparently present, possibly in the form of water of hydration. The very small phosphorus content is unexplained although it may be that the phosphorus is present as an impurity due to incomplete removal of the NaPF6 during the washing process.
These results show that lCH)X can be electrochemically oxidized in aqueous Solon and that even though oxygen is incorporated in some way into the film the conductivity of the material obtained is well into the metallic regime.

I

Example 29 Several experiments were carried out in an identical manner to those described in Example 24 except that a saturated solution of Nab in 50~ HO was employed in lieu of the NaPF6. Golden, flexible films having conductivities of about 1 ohm tam 1 were obtained. Elemental analysis of films from two separate experiments gave compositions corresponding to [Cal 05Bo.02~Fo,090,02]X
and [Cal buff x Electrochemical oxidation processes occur during the passage of the electric current in these experiments, but the conductivity levels obtained are lower than those for the systems in which NaAsF6 and NaPF6 solutions in 50~ HO were used.

I

Electrochemical p-doping of Polyparaphenylen2, (PUP), in Aqueous Solution Example 30 A loom diameter, loom pellet of PUP was annealed in vacua for 48 hours at 400C. It was then attached mechanically to a Pi wire and placed in an 0.5M solution of Pb~C104)2 in 12M HC104 loom from a lead counter electrode. The Eon (vs.
lead) of the PUP after a 30 minute immersion in the electrolyte was 1.08V. At this time it gave a short circuit current of Moe. It was then attached to the positive terminal and the lead attached to the negative terminal of a constant current do power supply for 1 hour at Moe. From the coulombs passed, the expected composition of the PUP was [(C6H4) (Kiwi 052]x (exclusive of chemical oxidation). After standing for 30 minutes in the electrolyte, the doped PUP exhibited an fox (vs. Pub) of 1.17V and a short circuit current of Moe.

I

Example 31 Example 30 was repeated using EM HC104. The fox (vs. Pub after 30 minutes was 0.92V and the corresponding short circuit current was Moe. After oxidizing electrochemically to a composition corresponding to ~(C6H4) (C104~ o 046~X
(exclusive of chemical oxidation) an Eon (vs. Pub) of 1.18V
was obtained after a 30 minute equilibration period. A short circuit current of Moe was recorded at that time.
Examples 26 and 27 demonstrate that pol~paraphenylene can be oxidized electrochemically in aqueous solution in a manner analogous to (Shucks, and that this system is reversible and can act as a rechargeable battery cello I
- I -(OH) as a Secondary Battery Electrode in HC104 and H2S04 Example 32 2 A tam piece of Claus rich shucks film is doped overnight in 12M HC104 to yield a chemically 11~ p-doped material having an Eon (vs. lead) of OVA. This material was then placed along with a lead counter electrode in an 0.5M
solution of Pb(C104)2 in 12M HC104. When the (SHUCKS and Pub electrodes of the above electrochemical cell were attached to the positive and negative terminals respectively of a do power supply at a constant voltage oxidation of 1.20V for about 8.5 minutes and the power supply was then disconnected, an immediate Eon (vs. lead) of about l.l9V was observed. The (OH) had therefore been very highly oxidized electrochemically in aqueous HC104. The potential fell during 2 hours, possibly in part because of diffusion of Dupont species from the exterior to the interior of (SHUCKS fibrils.
The value of Eon (versus lead) after 2 hours was about 0.94V, corresponding to a doping level of 15%. The (Clucks had been oxidized in aqueous HC104 to a degree beyond the 11% obtained by simple immersion of the (SHUCKS film in 12M HC104~ The E value fell further during the next 24 hour period to about OVA versus lead corresponding to a doping level of 12.2%, still in excess of that obtained chemically by immersing (Shucks film in 12 M HC104.
It is believed that the following electrochemical oxidation of the (SHUCKS occurred during the above "battery charging" reaction:
[OH 0 11(C104) 0 1l~x+0~02xPb(C10~)2 [OH (C104) 0 15]x+0.02xPb.
During discharge, the reverse reaction to that given above, the short circuit current observed, after two hours standing (potential [vs. Pub], 0.94V) was Moe.
Whether the observed decrease in Eon on standing is due to further slow diffusion of -the Dupont species into the interior of the (Shucks fibrils or whether it is due to slow reaction with air, to partial hydrolysis or to some other factor is not presently known. During the electrochemical fly oxidation and during the 24 hour standing period, the apparatus was exposed to air. All previous polymer batteries using organic electrolytes would have deteriorated completely in a few minutes, even at lower doping levels, under aerobic conditions It is believed that the battery cell can be repeatedly recycled between OVA (vs. Pub) and Levi (vs. Pub at high coulombic efficiency without discernible degradation. Due to the logarithmic form of the equation relating the potential of doped (SHUCKS to the percent oxidation, a very small change in voltage corresponds to a large change in percent doping at doping concentrations greater than about 10%. This is an ideal characteristic for an electrode in a secondary battery cell.

Z3~

Example 33 A battery cell similar to that of Example I was constructed from a tam , 4mg piece of cls-rich (SHUCKS film in 0.5M Pb(C104~2/12 M HC104 together with a lead counter electrode. The cell was "charged" at a constant voltage of Levi for 25.5 hours. The initial charging current was Moe and the final charging current was Moe. The short circuit current after subsequent standing for a period of 24 hours was in excess of 0.5 ampere and was sufficient to run a small electric motor and propeller. No previously known type of polymer electrochemical cell can accomplish this feat using lcm2 piece of polymer film.

I

Example 34 A lo x 1.5cm piece of Claus rich (SHUCKS film and a strip of lead were place in 12M H2S04 about loom apart.
After 30 minutes the polyacetylene film had an fox (vs. lead) of 0.60V. The (SHEA and Pub electrodes were then attached to the positive and negative electrodes respectively of a constant voltage (1.25V) dock power supply for 7~5 minutes. The coulombs passed corresponded to 6% oxidation of the (SHUCKS.
The Eon (vs. Pub) of the (SHUCKS electrode was 1.12V and on connecting the electrodes via an ammeter a short circuit current of Moe was observed. These observations suggest that this system also involves reversible electrochemistry suggestive of potential secondary battery applications.

'3..ff~3~ LO

All Polymer Electrode Batteries Example 35 One tam piece of is rich (SHUCKS film was placed in 12M HC104 containing dissolved Pb(C104)2 together with a Pub electrode. The piece of (Shucks film was attached to the positive terminal of a 1.2V deco power source an the lead electrode was attached to the negative terminal for 8 minutes.
This resulted in the (SHUCKS being oxidized to a greater extent than that obtained by chemical oxidation in the electrolyte.
The lead electrode was disconnected and a second lo piece of (SHUCKS placed in the electrolyte and connected to the first, electrochemically doped, piece of (SHUCKS via a voltmeter. A potential of 0.30V was observed and an unexpectedly large short circuit current was obtained (Moe).
After a 15 minute discharge the current had fallen to Moe.
The coulombic efficiency was 48%. This experiment suggests that a useful all-(CH)x rechargeable cell may be obtainable in this system. The overall discharge reaction is believed to be given by the equation.
[OH 'll(C10~) o 11] SHEA 178(C104) o 178]
SHEA ' (C104) o 144]x ~239L~

Example 36 Two tam x 1.5cm pieces of is rich (SHUCKS film were placed loom apart in a 12M H2S04 solution together with a piece of Pi foil. Both pieces of (Shucks were oxidized sequentially and electrochemically to 3% by attaching each one to the positive terminal and the Pi to the negative terminal respectively of a 0.75V constant voltage do power supply for a period of 8.5 minutes. The level of oxidation was calculated from the number of Columbus passed The two (SHUCKS electrodes were then attached to the terminals of an 0.75V constant potential power supply for 4 minutes so that the number of coulombs passed should oxidize one (SHUCKS electrode to 6% and reduce the other to neutral (SHUCKS. A potential difference of 0.48V was then observed between the two electrodes. On connecting them via an ammeter a short circuit current of Moe was observed. Upon continuing the short circuit discharge for 10 minutes the short circuit current fell to Moe. The coulombic efficiency was 23%.
The discharge reaction of this cell is believed to be Shucks (HS04) o 06]x SHEA ' Sue) O 03] .
Again, this system shows considerable potential for a rechargeable battery system.

Claims (106)

WHAT IS CLAIMED IS:

1. A secondary battery comprising an anode:
a cathode comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material; and an electrolyte, said electrolyte comprising a protic solvent and at least one ionic dopant capable of doping said polymer to a conductive state in said electrolyte.

2. The battery of claim 1 wherein said solvent comprises water.

3. The battery of claim 1 wherein said solvent comprises at least one alcohol or amine.

4. The battery of claim 1 wherein said polymer comprises at least one polyacetylene.

5. The battery of claim 1 wherein said polymer comprises at least one polyphenylene.

6. The battery of claim 1 wherein said dopant comprises a chemical group selected from the group consisting of halide ions, polyhalide ions, C1O4 , PF6 , HSO4 , AsF6 , AsF4 , SO3CF3 , and BF4 .

7. The battery of claim 1 wherein said dopant comprises a cation of a metal whose Pauling electronegativity is less than about 1.6 or an organic cation selected from the group consisting of (R4-XMHx)+ and R3E+ where R is alkyl or aryl; M is N, P, or As; E is O or S; and X is an integer from 0 to 4.

8. The battery of claim 7 wherein said metal comprises an alkali metal.

9. The battery of claim 7 wherein said metal comprises lithium.

10. The battery of claim 1 wherein said anode comprises a metal.

11. The battery of claim 1 wherein said anode comprises an alkali metal.

12. The battery of claim 1 wherein said anode comprises lead.

13. The battery of claim 1 wherein said anode comprises a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material.

14. The battery of claim 13 wherein each of said anode and cathode have been doped chemically to a conductive state by a dopant specie.

15. A secondary battery comprising a cathode;
an anode comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material; and an electrolyte, said electrolyte comprising a protic solvent and at least one ionic dopant capable of doping said polymer to a conductive state in said electrolyte.

16. The battery of claim 15 wherein said solvent comprises water.

17. The battery of claim 15 wherein said solvent comprises at least one alcohol or amine.

18. The battery of claim 15 wherein said polymer comprises at least one polyacetylene,

19. The battery of claim 15 wherein said polymer comprises at least one polyphenylene.

20. The battery of claim 15 wherein said dopant comprises a cation of a metal whose Pauling electronegativity is less than about 1.6 or an organic cation selected from the group consisting of (R4-XMHx)+ and R3E+ where R is alkyl or aryl; M is N, P or As;
E is O or S; and X is an integer from 0 to 4.

21. The battery of claim 15 wherein said dopant comprises a chemical group selected from the group consisting of halide ions, polyhalide ions, C1O4, PF6, HSO4, AsF6, AsF4, SO3CF3, and BF4.

22. The battery of claim 20 wherein said metal comprises an alkali metal.

23. The battery of claim 20 wherein said metal comprises lithium.

24. The battery of claim 15 wherein said cathode comprises a conjugated polymer having conjugated unsaturation along a main back-bone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material.

25. A secondary battery comprising an anode;
a cathode; and an electrolyte;
said anode and cathode each comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material;
said electrolyte comprising a protic solvent and at least one dopant capable of doping said polymer to a conductive state in said electrolyte;
the cathode polymer being electrochemically p-doped with said dopant to an oxidized state as compared with the anode polymer.

26. The battery of claim 25 wherein said solvent comprises water.

27. The battery of claim 25 wherein said solvent comprises at least one alcohol or amine.

28. The battery of claim 25 wherein said polymer comprises at least one polyacetylene.

29. The battery of claim 25 wherein said polymer comprises at least one polyphenylene.

30. The battery of claim 25 wherein said dopant comprises a chemical group selected from the group consisting of halide ions, polyhalide ions, C1O4 , PF6 , HSO4 , AsF4 , AsF6 , SO3CF3 , and BF4 .

31. The battery of claim 25 wherein said electrolyte comprises a cation of a metal whose Pauling electronegativity is less than about 1.6 or an organic cation selected from the group consisting of (R4-xMHx)+, and R3E+ where R is alkyl or aryl; M is M, P, or As: E is O or S; and X is an integer from 0 to 4.

32. The battery of claim 31 wherein said metal is an alkali metal.

33. The battery of claim 31 wherein said metal is lithium.

34. A secondary battery comprising an anode;
a cathode; and an electrolyte;
said anode and cathode each comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material;
said electrolyte comprising a protic solvent and at least one ionic dopant capable of doping said polymer to a conductive state in said electrolyte;
the anode polymer being electrochemically n-doped with said dopant to a reduced state as compared with the cathode polymer.

35. The battery of claim 34 wherein said solvent comprises water.

36. The battery of claim 34 wherein said solvent comprises at least one alcohol or amine.

37. The battery of claim 34 wherein said polymer comprises at least one polyacetylene.

38. The battery of claim 34 wherein said polymer comprises at least one polyphenylene.

39. The battery of claim 34 wherein said cathode comprises lead.

40. An electrochemical fuel cell comprising:
an electrochemically oxidizable fuel;
an electrochemically reducible oxidizing agent;
catalyst electrode means comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material;
an electrolyte in contact with said catalyst electrode comprising a protic solvent, and at least one ionic dopant capable of doping said polymer to a conductive state in the electrolyte; and second electrode means in contact with the electrolyte.

41. The cell of claim 40 wherein said solvent comprises water.

42. The cell of claim 40 wherein said solvent comprises at least one alcohol or amine.

43. The cell of claim 40 wherein said electrolyte comprises a material capable of participating in an oxidation-reduction reaction with the polymer.

44. The cell of claim 40 wherein said dopant is capable of participating in an oxidation-reduction reaction with the polymer.

45. The cell of claim 40 wherein said polymer comprises at least one polyacetylene.

46. The cell of claim 40 wherein said polymer comprises at least one polyphenylene.

47. The cell of claim 40 wherein said dopant comprises a chemical group selected from the group consisting of halide ions, polyhalide ions, C1O4 , PF6 , HSO4 , AsF6 , AsF4 , SO3CF3 , and BF4 .

48. The cell of claim 40 wherein said second electrode means comprises the fuel.

49. The cell of claim 48 wherein said second electrode means comprises a metal.

50. The cell of claim 48 wherein said second electrode means comprises lead.

51. The cell of claim 50 wherein said oxidizing agent comprises perchlorate.

52. The cell of claim 40 wherein said second electrode means comprises said oxidizing agent.

53. The cell of claim 40 wherein said fuel and said oxidizing agent comprises said dopant.

54. The cell of claim 40 which is substantially reversible.

55. The cell of claim 40 wherein each of said electrodes comprises a portion of a unitary mass of said polymer.

56. The cell of claim 40 wherein said fuel comprises an organic material.

57. The cell of claim 40 wherein said fuel comprises hydrazine.

58. The cell of claim 40 wherein said oxidizing agent comprises oxygen.

59. An electrochemical method for modifying the electrical conductivity of an organic polymer comprising providing an electrochemical cell comprising an anode, a cathode, at least one of said electrodes comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material; and an electrolyte comprising a protic solvent and at least one ionic dopant capable of doping the polymer to a conductive state in said electrolyte;
and passing current through the cell to effect said doping of the polymer to a more highly conducting state, said doping being substantially reversible.

60. The method of claim 59 wherein said solvent comprises water.

61. The method of claim 59 wherein said solvent comprises at least one alcohol or amine.

62. The method of claim 59 wherein said dopant is capable of participating in an oxidation-reduction reaction with said polymer.

63. The method of claim 59 wherein said polymer comprises at least one polyacetylene.

64. The method of claim 59 wherein said polymer comprises at least one polyphenylene.

65. The method of claim 59 wherein said dopant comprises a chemical group selected from the group consisting of halide ions, polyhalide ions, C1O4 , PF6 , HSO4 , AsF6 AsF4 , SO3CF3 , and BF4 .

66. The method of claim 59 wherein said dopant comprises a cation of a metal whose Pauling electronegative is less than about 1.6 or an organic cation selected from the group consisting of (R4-xMHx)+ and R3E+ where R
is alkyl or aryl; M is N, P or As; E is O or S; and X is an integer from 0 to 4.

67. The method of claim 65 wherein said dopant further comprises a cation of a metal whose Pauling electronegativity is less than about 1.6 or an organic cation selected from the group consisting of (R4-xMHx)+ and R3E+ where R is alkyl or aryl;
M is N, P, or As; E is O or S; and X is an integer from 0 to 4.

68. The method of claim 66 wherein said metal comprises an alkali metal.

69. The method of claim 66 wherein said metal comprises lithium.

70. The method of claim 67 wherein said metal comprises an alkali metal.

71. The method of claim 59 wherein each of said electrodes comprises a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material.

72. The method of claim 59 wherein at least one of the polymer electrodes has been doped chemically to a conductive state by a dopant species.

73. An electrochemical method for modifying the electrical conductivity of an organic polymer comprising providing an electrochemical cell comprising an anode, a cathode, and an electrolyte each of said anode and cathode comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material;
said electrolyte comprising a protic solvent and at least one ionic dopant capable of doping said polymer to a conductive state in said electrolyte; and passing current through the cell to effect oxidation of the cathode polymer with said dopant to an oxidized state as compared with the anode polymer.

74. An electrochemical method for modifying the electrical conductivity of an organic polymer comprising providing an electrochemical cell comprising an anode;
a cathode, and an electrolyte each of said anode and cathode comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material;
said electrolyte comprising a protic solvent and at least one ionic dopant capable of doping said polymer to a conductive state in said electrolyte; and passing current through the cell to effect electrochemical reduction of the anode polymer with said dopant to a reduced state as compared with the cathode polymer.

75. A method for the electrochemical generation of electric current comprising providing an electrochemical cell comprising an electrochemically oxidizable fuel;
an electrochemically reducible oxidizing agent;
an electrolyte;
catalyst electrode means in contact with the electrolyte comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material;
said electrolyte comprising a protic solvent, and an ionic dopant capable of doping said polymer to a conducting state in the electrolyte; and second electrode means in contact with the electrolyte; and operating the cell to effect at least a partial electrochemical oxidation of said fuel and at least a partial electrochemical reduction of said oxidizing agent.

76. The method of claim 75 wherein said solvent comprises water.

77. The method of claim 75 wherein said solvent comprises at least one alcohol or amine.

78. The method of claim 75 wherein said dopant is capable of participating in an oxidation-reaction with the polymer.

79. The method of claim 75 wherein said polymer comprises at least one polyacetylene.

80. The method of claim 75 wherein said polymer comprises at least one polyphenylene.

81. The method of claim 75 wherein said dopant comprises a chemical group selected from the group consisting of halide ions, polyhalide ions, C1O4 , PF6 , HSO4 , AsF6 , AsF4 , SO3CF3 , and BF4 .

82. The method of claim 75 wherein said second electrode means comprises the fuel.

83. The method of claim 82 wherein said second electrode means comprises a metal.

84. The method of claim 82 wherein said second electrode means comprises lead.

85. The method of claim 82 wherein said oxidizing agent comprises perchlorate.

86. The method of claim 75 wherein said fuel comprises an organic material.

87. The method of claim 75 wherein said fuel comprises hydrazine.

88. The method of claim 75 wherein said oxidizing agent comprises oxygen.

89. The method of claim 82 wherein said second electrode means comprises lead and each of said dopant and said oxidizing agent comprises perchlorate.

90. The method of claim 75 wherein said second electrode means comprises said oxidizing agent.

91. The method of claim 75 which is substantially reversible.

92. A method for modifying the electrical conductivity of an organic polymer comprising providing an anode, and a cathode, at least one of said electrodes comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electrochemically reducible to an n-type doped material, and contacting said polymer with an electrolyte comprising a protic solvent, at least one ionic dopant capable of doping said polymer to a conductive state in the electrolyte, and a material capable of participating in an oxidation-reduction reaction with the polymer.

93. The method of claim 92 wherein said solvent comprises water.

94. The method of claim 92 wherein said solvent comprises at least one alcohol or amine.

95. The method of claim 92 wherein said polymer comprises at least one polyacetylene.

96. The method of claim 92 wherein said polymer comprises at least one polyphenylene.

97. The method of claim 92 wherein said material is an oxidizing acid.

98. The method of claim 97 wherein said material comprises said dopant.

99. The method of claim 92 wherein said material is a reducing base.

100. The method of claim 99 wherein said material comprises said dopant.

101. The method of claim 92 wherein said material is a gas.

102. The method of claim 92 wherein each of said electrodes comprises said polymer.

103. The method of claim 102 wherein each of said electrodes is contacted with different material capable of participating in an oxidation-reduction reaction with said polymers.

104. The method of claim 103 wherein each of said materials is a gas.

105. The method of claim 102 wherein each of said electrodes comprises a portion of a unitary mass of said polymer.

106. An electrochemical cell comprising first and second electrodes, at least one of said electrodes comprising a conjugated polymer having conjugated unsaturation along a main backbone chain thereof, said polymer being electrochemically oxidizable to a p-type doped material and electro-chemically reducible to an n-type doped material, and an electrolyte, said electrolyte comprising a protic solvent and at least one ionic dopant capable of doping said polymer to a conductive state in said electrolyte.